Preface

The definition of a colloidal particle is a micro/nanometer-sized solid particle uniformly dispersed in a solution. In colloidal dispersions, there are two phase systems: continuous phase and dispersed phase (ranging from 1 nm to 1 µm). The colloidal particle/nanoparticle is produced by considering various key factors such as particle size, distribution, polarity, and surface properties. The stability of colloidal dispersion has a role in homogeneous distribution with steric and electrostatic modifications.

Recently, colloidal and nanotechnological approaches have been considered as advanced technologies. Nanotechnology is known as scientific and engineering knowledge that makes it possible to use nanosized materials in special applications. Nanotechnology has developed science and technology by producing superior products and it has a multidisciplinary approach. Nanotechnological products have attracted much attention with many new studies concentrating on colloids and nanoparticles in biotechnology for biomedical and environmental applications. Materials science, engineering, medicine, dentistry, drug delivery, etc. have all used this approach. Knowledge of nanoscience and nanoengineering is being used to produce nanotechnology-based products such as nanoparticles, nanolayers, nanocomposites, nanofibers, oil-in-water nanoemulsions, cyclodextrin-nanosponges, etc. Colloidal particles/ nanoparticles are preferred because of their biocompatibility and performance in pharmaceutical applications. For this purpose, colloidal particles are also widely used in the development of novel drug delivery systems for use in diagnosis and treatment.

*Colloid Science in Pharmaceutical Nanotechnology* is comprised of seven chapters that provide an overview of colloidal particle and nanoparticle systems, their physicochemical properties, and pharmaceutical applications. Some of the topics covered are nanoparticle-based drug design, the miscibility of colloidal particles, and the stability of nanoparticles. The preparation and characterization of colloidal systems are discussed in detail. In this book, the authors focus on recent studies, applications, and new technological developments of the fundamental properties of colloidal particle systems. Readers will be able to access recent studies, applications, and new technological developments on colloidal systems. We sincerely thank our authors who have contributed with experience and knowledge to this book. Especially, our thanks go to Erbil Karakuş, Emir Ersel Karakuş and the editorial team from IntechOpen for their assistance in preparing this book.

> **Selcan Karakuş** Assistant Professor, Department of Chemistry, Faculty of Engineering, Istanbul, Turkey

> > University-Cerrahpasa, Istanbul, Turkey

Section 1

Colloid Science and

Nanoparticles

1

Section 1

## Colloid Science and Nanoparticles

Chapter 1

Abstract

polymeric nanoparticles

and ultrasonic irradiation [9].

1. Introduction

3

The Viscosity Behaviour of

Gum/Rosin Ester Polymeric

Selcan Karakus, Merve Ilgar, Ezgi Tan, Yeşim Müge Sahin,

In this study, PEGylated locust bean gum–rosin glycerol ester polymeric nanoparticles (PEG-LBG/RE PNPs) were synthesized by using simple ultrasonic irradiation method. The nanoparticles were characterized by using Fourier-

for drug delivery systems in biomedical and pharmaceutical applications.

Keywords: ultrasonic-assisted, locust bean gum, rosin glycerol ester,

transform infrared spectroscopy (FTIR) and scanning transmission electron microscopy (STEM). The viscosity behaviors of nanoparticles were studied in different conditions (pH, sonication time, and salt). The experimental results were calculated by Huggins, Kraemer, Tanglertpaibul-Rao, and Higiro models to understand the colloidal stability, the miscibility mechanism, and coefficients of nanoparticles. The results confirmed that the homogenous distribution of nanostructure was related to sonication time (30 min) and the presence of NaOH salt. With the addition of NaOH, the nanosystem based on ionotropic gelation technique was made more homogeneous. The results made us think that nanoparticles can be a good candidate

Colloidal nanoparticles (CNPs) have attracted attention in industrial applications (food, pharmaceuticals, cosmetics, ink, rubber, and water treatment) due to their biological, mechanical, and thermal properties and stability in solution. Their superior properties depend on the high surface area, small size, and uniform morphologies [1–3]. CNPs are prepared to use different methods such as sol–gel [4], photochemical [5], electrochemical [6], laser ablation [7], ionizing irradiations [8],

The ultrasonic irradiation synthesis of different morphologies of nanomaterials consisted of metal/metal oxides, and polymeric materials have received considerable attention in the nanotechnology applications. The ultrasonic irradiation (20 kHz to 10 MHz) method has been employed in the preparation of the high purity, the uniform shape, and the nanosized distribution of nanomaterials.

PEGylated Locust Bean

Nevin Tasaltin and Ayben Kilislioglu

Nanoparticles

#### Chapter 1

## The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles

Selcan Karakus, Merve Ilgar, Ezgi Tan, Yeşim Müge Sahin, Nevin Tasaltin and Ayben Kilislioglu

#### Abstract

In this study, PEGylated locust bean gum–rosin glycerol ester polymeric nanoparticles (PEG-LBG/RE PNPs) were synthesized by using simple ultrasonic irradiation method. The nanoparticles were characterized by using Fouriertransform infrared spectroscopy (FTIR) and scanning transmission electron microscopy (STEM). The viscosity behaviors of nanoparticles were studied in different conditions (pH, sonication time, and salt). The experimental results were calculated by Huggins, Kraemer, Tanglertpaibul-Rao, and Higiro models to understand the colloidal stability, the miscibility mechanism, and coefficients of nanoparticles. The results confirmed that the homogenous distribution of nanostructure was related to sonication time (30 min) and the presence of NaOH salt. With the addition of NaOH, the nanosystem based on ionotropic gelation technique was made more homogeneous. The results made us think that nanoparticles can be a good candidate for drug delivery systems in biomedical and pharmaceutical applications.

Keywords: ultrasonic-assisted, locust bean gum, rosin glycerol ester, polymeric nanoparticles

#### 1. Introduction

Colloidal nanoparticles (CNPs) have attracted attention in industrial applications (food, pharmaceuticals, cosmetics, ink, rubber, and water treatment) due to their biological, mechanical, and thermal properties and stability in solution. Their superior properties depend on the high surface area, small size, and uniform morphologies [1–3]. CNPs are prepared to use different methods such as sol–gel [4], photochemical [5], electrochemical [6], laser ablation [7], ionizing irradiations [8], and ultrasonic irradiation [9].

The ultrasonic irradiation synthesis of different morphologies of nanomaterials consisted of metal/metal oxides, and polymeric materials have received considerable attention in the nanotechnology applications. The ultrasonic irradiation (20 kHz to 10 MHz) method has been employed in the preparation of the high purity, the uniform shape, and the nanosized distribution of nanomaterials.

This method causes the formation of the acoustic cavitations which consist of the bubbles [10]. The growth and collapse of bubbles are related to the transfer of energy at high pressures and temperatures due to the highly reactive free radicals such as hydrogen radicals (H•) and hydroxyl radicals (OH•). Bubbles generate three zones, such as a hot spot (5000°C, 500 atm), a gas–liquid interface (300°C, 50 atm), and a bulk solution (25°C, 1 atm) [11].

purchased from Merck. Rosin glycerol ester was purchased from Pina Kimya (CAS: 8050-26-8, EC: 232–479-9, Turkey). All other reagents and chemicals were of ana-

The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles

PEG-LBG/RE PNPs were synthesized using the ultrasonic irradiation method (Ultrasonics Vibra-Cell, probe type, amplitude %30, a frequency of 20 kHz) with different ratios of blends (PEG-LBG: 1:1, 1:2). In the procedure, two phases were

The continuous phase: 125 mg LBG was dissolved in 50 ml of distilled water (60°C

The dispersion phase: 0.01 g RE was dissolved in 0.5 ml DMSO and then 7 ml ethyl

The dynamics viscosities of LBG, PEG-LBG, and PEG-LBG/RE were determined by a programmable AND viscometer (SV-10, Sine-wave Vibro Viscometer, A δ D Company). PEG-LBG/RE PNPs were scanned in the dark field area with the wet STEM detector by using FEI QUANTA S50 (A copper grid, Ted Pella, support films, carbon type A, 300 meshes was utilized). STEM holder was cooled to 2°C and the pressure was set between 700 and 1300 Pa. Samples were ground with KBr powder and analyzed from 4000 to 600 cm�<sup>1</sup> with a resolution of 4 cm�<sup>1</sup> using 8 scans by

The changes in viscosity values of LBG, PEG-LBG, and PEG-LBG/RE PNPs were investigated in a dilute solution (50 mL) at different ratios of polymer blends (PEG-LBG: 1:1 and 1:2), temperatures (25 and 35°C), and sonication times (10–70 min) in

> C!0 ηsp C

Multi-concentration regression models:

Tanglertpaibul-Rao ηrel ¼ 1 þ ½ � η C (5) [34] Higiro <sup>η</sup>rel <sup>¼</sup> <sup>e</sup>½ � <sup>η</sup> <sup>C</sup> (6) [28]

The equations of the intrinsic viscosity, the specific viscosity, and the multi-concentration regression models.

Formula Ref:

<sup>t</sup><sup>0</sup> � 1 (1) [31]

C (k1, Huggins constant) (3) [32]

C (k2, Kraemer constant) (4) [33]

(2) [31]

7.5 ml of continuous phase and the dispersed phase was sonicated at room temperature. 42.5 ml of continuous phase was then added slowly to the blends, and the sonication procedure was continued for 30 minutes. The final solution was evaporated at room temperature for 14 hours until ethyl acetate completely evaporated in the solution. Polymer blends were also performed for different composition

for 20 min) and then added to 125 mg of PEG400 polymer solution at room

2.2 Preparation of PEG-LBG/RE polymeric nanoparticles

prepared such as the dispersion phase and the continuous phase.

lytical grade.

temperature.

acetate was added to the solution.

DOI: http://dx.doi.org/10.5772/intechopen.90248

ratios (PEG-LBG) such as 1:1 and 1:2.

using a PerkinElmer FTIR emission spectrometer.

Specific viscosity <sup>η</sup>sp <sup>¼</sup> <sup>t</sup>

Intrinsic viscosity ½ �¼ <sup>η</sup> lim

=

=

<sup>C</sup> <sup>¼</sup> ½ �þ <sup>η</sup> <sup>k</sup>1½ � <sup>η</sup> <sup>2</sup>

<sup>C</sup> <sup>¼</sup> ½ �þ <sup>η</sup> <sup>k</sup>2½ � <sup>η</sup> <sup>2</sup>

Huggins <sup>η</sup>sp

Kraemer In <sup>η</sup>rel

Table 1.

5

2.4 Calculations of the multi-concentration regression models

2.3 Characterization parts

In recent research, different structures of nanoparticles such as TiO2 [12], ZnO [13], starch [14], alumina/carbon core-shell [15], lipid-polymer hybrid [16], and biopolymeric [17, 18] nanoparticles have been synthesized with the ultrasonic irradiation method. Generally, biopolymeric nanoparticles have used in the field of foods encapsulation and drug delivery studies due to the biodegradability, biocompatibility, and low toxicity properties. Alginate [19], chitosan [20], carboxymethyl cellulose/gelatin [21], Senegal gum [22], guar gum [23], xanthan gum [24], Senna tora gum [25], and locust bean gum (LBG) [26] are natural biopolymers employed in industrial processes [24]. Locust bean gum is a neutral polysaccharide and has a mannose backbone with single side chain galactose units [25–27].

When the studies in the current literature are examined, it has been found that there are very few studies on LGB based on nanoparticles [28–30]. It was found that no studies were performed on the locust nanostructures containing rosin gum and derivatives. In this work, the ultrasonic irradiation method was used for the preparation of novel PEGylated locust bean gum (PEG-LBG)/rosin glycerol ester (RE) polymeric nanoparticles (PNPs) at room temperature. The present research work was aimed at the colloidal stability, the viscosity behaviour, and miscibility of binary polymer blends of PEG and LBG PNPs due to the intrinsic viscosity. The intrinsic viscosity of the polymer is a significant molecular characteristic, depending on the size of the polymer chain, molecular weight, and radius of rotation of the polymer in dilute solution. The voluminosity (VE), shape factor (υ), the intrinsic viscosity [η], and Krigbaum and Wall miscibility parameter (Δb) of polymeric nanoparticles were calculated from different models such as Huggins, Kraemer, Tanglertpaibul-Rao, and Higiro [17]. The values of intrinsic viscosities were used to determine the rheological behaviour of the PEG-LBG/RE PNPs at different conditions (pH, sonication time, and salt). The homogeneous distributions of PEG with LGB had an influence on the blends ratio of PEG/LBG (1:1, 1:2), sonication time (10–70 min.), temperature (25–35°C), and salts (NaOH, KOH, CTAB). With the addition of NaOH salt, PEG-LBG/RE PNPs based on ionotropic gelation technique were made into a more homogeneous solution. The PEG-LBG/ RE PNPs were characterized to examine surface morphologies using a Fouriertransform infrared spectroscopy (FTIR) and scanning transmission electron microscopy (STEM). The aim of this study was to provide an investigation of rosin ester-based nanoparticle distributions in LGB and understand the role of polymer– particle interactions with respect to nanoparticle concentration as well to use the candidate nanocarrier for biomedical applications.

#### 2. Materials and methods

#### 2.1 Materials

Locust bean gum from Ceratonia siliqua seeds (M.W. of approx. 310 kDa) was purchased from Sigma Aldrich. Polyethylene glycol (PEG 400) was obtained from Fluka (Switzerland). Ethyl acetate (anhydrous, 99.8%) was purchased from Sigma Aldrich. Dimethyl sulfoxide (DMSO), potassium hydroxide (KOH), sodium hydroxide (NaOH), and cetyltrimethylammonium bromide (CTAB) were

The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles DOI: http://dx.doi.org/10.5772/intechopen.90248

purchased from Merck. Rosin glycerol ester was purchased from Pina Kimya (CAS: 8050-26-8, EC: 232–479-9, Turkey). All other reagents and chemicals were of analytical grade.

#### 2.2 Preparation of PEG-LBG/RE polymeric nanoparticles

PEG-LBG/RE PNPs were synthesized using the ultrasonic irradiation method (Ultrasonics Vibra-Cell, probe type, amplitude %30, a frequency of 20 kHz) with different ratios of blends (PEG-LBG: 1:1, 1:2). In the procedure, two phases were prepared such as the dispersion phase and the continuous phase.

The continuous phase: 125 mg LBG was dissolved in 50 ml of distilled water (60°C for 20 min) and then added to 125 mg of PEG400 polymer solution at room temperature.

The dispersion phase: 0.01 g RE was dissolved in 0.5 ml DMSO and then 7 ml ethyl acetate was added to the solution.

7.5 ml of continuous phase and the dispersed phase was sonicated at room temperature. 42.5 ml of continuous phase was then added slowly to the blends, and the sonication procedure was continued for 30 minutes. The final solution was evaporated at room temperature for 14 hours until ethyl acetate completely evaporated in the solution. Polymer blends were also performed for different composition ratios (PEG-LBG) such as 1:1 and 1:2.

#### 2.3 Characterization parts

This method causes the formation of the acoustic cavitations which consist of the bubbles [10]. The growth and collapse of bubbles are related to the transfer of energy at high pressures and temperatures due to the highly reactive free radicals such as hydrogen radicals (H•) and hydroxyl radicals (OH•). Bubbles generate three

In recent research, different structures of nanoparticles such as TiO2 [12], ZnO [13], starch [14], alumina/carbon core-shell [15], lipid-polymer hybrid [16], and biopolymeric [17, 18] nanoparticles have been synthesized with the ultrasonic irradiation method. Generally, biopolymeric nanoparticles have used in the field of foods encapsulation and drug delivery studies due to the biodegradability, biocompatibility, and low toxicity properties. Alginate [19], chitosan [20], carboxymethyl cellulose/gelatin [21], Senegal gum [22], guar gum [23], xanthan gum [24], Senna tora gum [25], and locust bean gum (LBG) [26] are natural biopolymers employed in industrial processes [24]. Locust bean gum is a neutral polysaccharide and has a

When the studies in the current literature are examined, it has been found that there are very few studies on LGB based on nanoparticles [28–30]. It was found that no studies were performed on the locust nanostructures containing rosin gum and derivatives. In this work, the ultrasonic irradiation method was used for the preparation of novel PEGylated locust bean gum (PEG-LBG)/rosin glycerol ester (RE) polymeric nanoparticles (PNPs) at room temperature. The present research work was aimed at the colloidal stability, the viscosity behaviour, and miscibility of binary polymer blends of PEG and LBG PNPs due to the intrinsic viscosity. The intrinsic viscosity of the polymer is a significant molecular characteristic,

depending on the size of the polymer chain, molecular weight, and radius of rotation of the polymer in dilute solution. The voluminosity (VE), shape factor (υ), the intrinsic viscosity [η], and Krigbaum and Wall miscibility parameter (Δb) of polymeric nanoparticles were calculated from different models such as Huggins, Kraemer, Tanglertpaibul-Rao, and Higiro [17]. The values of intrinsic viscosities were used to determine the rheological behaviour of the PEG-LBG/RE PNPs at different conditions (pH, sonication time, and salt). The homogeneous distributions of PEG with LGB had an influence on the blends ratio of PEG/LBG (1:1, 1:2), sonication time (10–70 min.), temperature (25–35°C), and salts (NaOH, KOH, CTAB). With the addition of NaOH salt, PEG-LBG/RE PNPs based on ionotropic gelation technique were made into a more homogeneous solution. The PEG-LBG/ RE PNPs were characterized to examine surface morphologies using a Fouriertransform infrared spectroscopy (FTIR) and scanning transmission electron microscopy (STEM). The aim of this study was to provide an investigation of rosin ester-based nanoparticle distributions in LGB and understand the role of polymer– particle interactions with respect to nanoparticle concentration as well to use the

Locust bean gum from Ceratonia siliqua seeds (M.W. of approx. 310 kDa) was purchased from Sigma Aldrich. Polyethylene glycol (PEG 400) was obtained from Fluka (Switzerland). Ethyl acetate (anhydrous, 99.8%) was purchased from Sigma Aldrich. Dimethyl sulfoxide (DMSO), potassium hydroxide (KOH), sodium hydroxide (NaOH), and cetyltrimethylammonium bromide (CTAB) were

zones, such as a hot spot (5000°C, 500 atm), a gas–liquid interface (300°C,

mannose backbone with single side chain galactose units [25–27].

50 atm), and a bulk solution (25°C, 1 atm) [11].

Colloid Science in Pharmaceutical Nanotechnology

candidate nanocarrier for biomedical applications.

2. Materials and methods

2.1 Materials

4

The dynamics viscosities of LBG, PEG-LBG, and PEG-LBG/RE were determined by a programmable AND viscometer (SV-10, Sine-wave Vibro Viscometer, A δ D Company). PEG-LBG/RE PNPs were scanned in the dark field area with the wet STEM detector by using FEI QUANTA S50 (A copper grid, Ted Pella, support films, carbon type A, 300 meshes was utilized). STEM holder was cooled to 2°C and the pressure was set between 700 and 1300 Pa. Samples were ground with KBr powder and analyzed from 4000 to 600 cm�<sup>1</sup> with a resolution of 4 cm�<sup>1</sup> using 8 scans by using a PerkinElmer FTIR emission spectrometer.

#### 2.4 Calculations of the multi-concentration regression models

The changes in viscosity values of LBG, PEG-LBG, and PEG-LBG/RE PNPs were investigated in a dilute solution (50 mL) at different ratios of polymer blends (PEG-LBG: 1:1 and 1:2), temperatures (25 and 35°C), and sonication times (10–70 min) in


#### Table 1.

The equations of the intrinsic viscosity, the specific viscosity, and the multi-concentration regression models.

the presence of NaOH, KOH, and CTAB salts. The specific viscosities (ηspÞ, the intrinsic viscosities ([η]), and the multi-concentration regression models of PEG-LBG/RE PNPs were calculated by using an AND viscometer (WinCT-Viscosity software) in 50 ml solution at constant temperature [31–36] (Table 1).

In this study, the voluminosity (VE), shape factor (υ), and Krigbaum and Wall parameter (Δb) were calculated using the following Eqs. 7–10, respectively. The polymer blends are miscible if Δb≥0 and immiscible when Δb<0. (b<sup>∗</sup> 12, the experimental interaction parameter; b12, the theoretical interaction parameter):

$$\gamma = \frac{\eta\_{\rm rel}^{0.5} - \mathbf{1}}{C \left(1.35 \eta\_{\rm rel}^{0.5} - \mathbf{0}.\mathbf{1}\right)}\tag{7}$$

$$\left[\eta\right] = \nu V\_E \tag{8}$$

$$b\_{12}^{\*} = \sqrt{b\_{11}b\_{22}}\tag{9}$$

$$
\Delta b = b\_{12} - b\_{12}^\* \tag{10}
$$

#### 3. Results and discussions

#### 3.1 Colloidal stability and viscosity analysis

#### 3.1.1 The multi-concentration regression models and salt factor

The intrinsic viscosity of [η] of PEG, LBG, PEG-LBG (1:1), and PEG-LBG/RE 1:1 nanoparticles was calculated using the multi-concentration regression models (Huggins, Kraemer, Tanglertpaibul-Rao, and Higiro models) at room temperatures. The correlation coefficient (R2 ), the intrinsic viscosity, and parameters of Huggins,


#### Table 2.

The intrinsic viscosity (ml/g) values of PEG-LBG blends and PEG-LBG/RE nanoparticles at room temperature for different concentrations.


Kraemer, Tanglertpaibul-Rao, and Higiro models were given comparatively in Table 2 (Figures 1–4). In this study, we focused on the effect of nanoparticles on the morphology of immiscible polymer blends. We found that PEG-LBG/RE PNPs

The Huggins, Kraemer, Tanglertpaibul-Rao, and Higiro plots of the intrinsic viscosities were calculated at different blend ratios, and the results showed the critical role on relation between the intrinsic viscosities and the blend ratios.

(1:2) were immiscible due to the mixing ratio of PEG-LBG (Table 3).

The Kraemer plots of PEG, LBG, PEG-LBG (1:1), and PEG-LBG/RE PNPs.

The Huggins plots of PEG, LBG, PEG-LBG (1:1), and PEG-LBG/RE PNPs.

The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles

DOI: http://dx.doi.org/10.5772/intechopen.90248

Figure 1.

Figure 2.

7

#### Table 3.

Voluminosity and shape factor of LBG, PEG-LBG, and PEG-LBG/RE PNPs.

The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles DOI: http://dx.doi.org/10.5772/intechopen.90248

Figure 1. The Huggins plots of PEG, LBG, PEG-LBG (1:1), and PEG-LBG/RE PNPs.

Figure 2. The Kraemer plots of PEG, LBG, PEG-LBG (1:1), and PEG-LBG/RE PNPs.

Kraemer, Tanglertpaibul-Rao, and Higiro models were given comparatively in Table 2 (Figures 1–4). In this study, we focused on the effect of nanoparticles on the morphology of immiscible polymer blends. We found that PEG-LBG/RE PNPs (1:2) were immiscible due to the mixing ratio of PEG-LBG (Table 3).

The Huggins, Kraemer, Tanglertpaibul-Rao, and Higiro plots of the intrinsic viscosities were calculated at different blend ratios, and the results showed the critical role on relation between the intrinsic viscosities and the blend ratios.

the presence of NaOH, KOH, and CTAB salts. The specific viscosities (ηspÞ, the intrinsic viscosities ([η]), and the multi-concentration regression models of PEG-LBG/RE PNPs were calculated by using an AND viscometer (WinCT-Viscosity

In this study, the voluminosity (VE), shape factor (υ), and Krigbaum and Wall

rel � 1

rel � <sup>0</sup>:<sup>1</sup> � � (7)

½ �¼ η υVE (8)

), the intrinsic viscosity, and parameters of Huggins,

k2 R<sup>2</sup> [η]

VE (ml/g) υ Δb (mL/g)<sup>2</sup> Miscibility

Rao

(ml/g)

Higiro

R2

R2 [η] (ml/g)

p (9)

<sup>12</sup> (10)

12, the

software) in 50 ml solution at constant temperature [31–36] (Table 1).

parameter (Δb) were calculated using the following Eqs. 7–10, respectively. The polymer blends are miscible if Δb≥0 and immiscible when Δb<0. (b<sup>∗</sup>

<sup>γ</sup> <sup>¼</sup> <sup>η</sup>0:<sup>5</sup>

b∗

3. Results and discussions

The correlation coefficient (R2

pH [η] (ml/g)

for different concentrations.

Table 2.

Table 3.

6

3.1 Colloidal stability and viscosity analysis

Colloid Science in Pharmaceutical Nanotechnology

k1 � 10�<sup>3</sup>

3.1.1 The multi-concentration regression models and salt factor

R2 [η] (ml/g)

experimental interaction parameter; b12, the theoretical interaction parameter):

C 1:35η0:<sup>5</sup>

<sup>12</sup> <sup>¼</sup> ffiffiffiffiffiffiffiffiffiffiffiffi b11b<sup>22</sup>

The intrinsic viscosity of [η] of PEG, LBG, PEG-LBG (1:1), and PEG-LBG/RE 1:1

Huggins Kraemer Tanglertpaibul-

A 4.70 0.213 0.99 6.73 1.129 0.89 9.11 0.96 10.87 0.98 B 5.18 0.193 0.99 56.75 �0.075 0.87 41.32 0.98 12.68 0.99 C 2.25 0.445 0.96 71.95 �0.067 0.86 41.57 1.00 12.65 0.99 D 0.67 1.493 0.99 55.78 �0.073 0.87 43.94 1.00 10.97 0.99 Samples: (A) PEG, (B) LBG, (C) PEG-LBG/ (1:1), (D) PEG-LBG/RE (1:2), and (E) PEG-LBG/RE (1:1).

The intrinsic viscosity (ml/g) values of PEG-LBG blends and PEG-LBG/RE nanoparticles at room temperature

PEG-LBG (1:1) 38 2:5> spherical 1.59 Miscible PEG-LBG/RE PNPs (1:2) 42 — �0.64 İmmiscible PEG-LBG/RE PNPs (1:1) 35 2.5 > spherical 1.56 Miscible

Voluminosity and shape factor of LBG, PEG-LBG, and PEG-LBG/RE PNPs.

nanoparticles was calculated using the multi-concentration regression models (Huggins, Kraemer, Tanglertpaibul-Rao, and Higiro models) at room temperatures.

<sup>Δ</sup><sup>b</sup> <sup>¼</sup> <sup>b</sup><sup>12</sup> � <sup>b</sup><sup>∗</sup>

Figure 3. The Tanglertpaibul-Rao's plots of PEG, LBG, PEG-LBG (1:1), and PEG-LBG/RE PNPs.

Figure 4. The Higiro plots of PEG, LBG, PEG-LBG (1:1), and PEG-LBG/RE PNPs.

The Tanglertpaibul-Rao model and Huggins model (R2 = 0.96–1.00) were the best models to understand the intrinsic viscosity of PEG, LBG, PEG-LBG, and PEG-LBG/RE PNPs. Behrouzian et al. [32] reported that the Tanglertpaibul and Rao model was the best model for the intrinsic viscosity determination of cress seed gum solutions. Razavi et al. [37] reported that the best model was Tanglertpaibul and Rao model for wild sage seed gum. In this study, the intrinsic viscosity of PEG-LBG/RE PNPs in the presence of different salts (NaOH, KOH, and CTAB) was investigated (Csalt, 0.1 M; Vsalt, 2 mL; Vsolution; 50 mL) at 25°C. The effect of NaOH, KOH, and CTAB salts on the values of intrinsic viscosity of PEG-LBG/RE PNPs (1:1) was

Plots of [η] of PEG-LBG/RE PNPs at different temperatures (25 and 35°C).

Plots of the intrinsic viscosity versus C of PEG-LBG/RE PNPs in the presence of salts (KOH, NaOH, and

The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles

DOI: http://dx.doi.org/10.5772/intechopen.90248

presented in Figure 5.

Figure 6.

9

Figure 5.

CTAB).

The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles DOI: http://dx.doi.org/10.5772/intechopen.90248

Figure 5. Plots of the intrinsic viscosity versus C of PEG-LBG/RE PNPs in the presence of salts (KOH, NaOH, and CTAB).

Figure 6. Plots of [η] of PEG-LBG/RE PNPs at different temperatures (25 and 35°C).

solutions. Razavi et al. [37] reported that the best model was Tanglertpaibul and Rao model for wild sage seed gum. In this study, the intrinsic viscosity of PEG-LBG/RE PNPs in the presence of different salts (NaOH, KOH, and CTAB) was investigated (Csalt, 0.1 M; Vsalt, 2 mL; Vsolution; 50 mL) at 25°C. The effect of NaOH, KOH, and CTAB salts on the values of intrinsic viscosity of PEG-LBG/RE PNPs (1:1) was presented in Figure 5.

The Tanglertpaibul-Rao model and Huggins model (R2 = 0.96–1.00) were the best models to understand the intrinsic viscosity of PEG, LBG, PEG-LBG, and PEG-LBG/RE PNPs. Behrouzian et al. [32] reported that the Tanglertpaibul and Rao model was the best model for the intrinsic viscosity determination of cress seed gum

The Higiro plots of PEG, LBG, PEG-LBG (1:1), and PEG-LBG/RE PNPs.

The Tanglertpaibul-Rao's plots of PEG, LBG, PEG-LBG (1:1), and PEG-LBG/RE PNPs.

Colloid Science in Pharmaceutical Nanotechnology

Figure 3.

Figure 4.

8

The pH values of the solutions (LBG, PEG-LBG, and PEG-LBG/RE PNPs) at initial pH in KOH, NaOH, and CTAB salt additions were determined: pHinitial, 5.7; pHinitial, 5.55; and pHinitial, 5.32, respectively. In the presence of salt, the values of the intrinsic viscosity for the mixture were observed to change in two different salts such as KOH (pHfinal: 5.93) and NaOH (pHfinal: 5.72). The [η] values for PEG-LBG/ RE PNPs (1:1) did not exhibit distinctive changes in the presence of CTAB (pHfinal: 3.87). Jiang et al. [38] reported that the interactions between blends were dependent on the ionic strength at low salt concentration which was related to the increase of salt concentration. Consequently the addition of NaOH and KOH showed the electrostatic repulsion between charges along the backbone of the polymer blends.

#### 3.1.2 Temperature and sonication time factor

The intrinsic viscosity decreased when the temperature increased, and the relation of the experimental results of PEG-LBG/RE PNPs with the temperature was shown in Figure 6.

However, when PEG-LBG/RE PNPs were sonicated, the intrinsic viscosity decreased for 30 minutes but remained constant after a period of time. These results had proven that the sonication time changed the value of viscosity and was effective on the blends (30% amp., 25°C) (Figure 7). The viscosity of Cu-ethylene glycol (EG) nanofluids was proven to decrease with the sonication time [39]. In this study, we found a similar situation, and demonstrated that sonication time changes the viscosity, which has a role on the formation of nanoparticles.

> In this study, we predicted the size and shape factor of PEG-LBG (1:1), PEG-LBG/RE PNPs (1:1), and PEG-LBG/RE PNPs (1:2) using the values of the intrinsic viscosity, associated with the shape factor, which were used to determine the change in the structure configuration. We calculated the shape and the Krigbaum and Wall (Δb) parameters of PEG-LBG/RE PNPs (1:1) using the intrinsic viscosity to determine the changes in the blends. We found that PEG-LBG/RE PNPs (1:1) had a spherical-like configuration, and the amounts of PEG had a role on the miscibility

The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles

The FTIR spectra of pure LBG, pure RE, and PEG-LBG/RE PNPs were shown in

The FTIR spectrum of pure LBG showed a broad absorption peak at 3250 cm<sup>1</sup> (stretching of -OH group), 2952 cm<sup>1</sup> (stretching of –CH), 1748 cm<sup>1</sup> (stretching of C=O), and 1000–1100 cm<sup>1</sup> (stretching of C-O-H). Upadhyay et al. [41] and

Chakravorty et al. [42] found the FTIR spectrum data similar. The FTIR spectrum of

(stretching of C=O), and 1120 cm<sup>1</sup> (stretching of C-O-H). As we have seen from the FTIR results, we have demonstrated that the apparent OH peak of LBG disappeared

According to the STEM image of PEG-LBG/RE PNPs (160.000x and 300.000x), we can see that the interior structure of the polymeric nanoparticle is LBG with the size lower than 50 nm. We are able to tell that these particles are small agglomerates

pure RE showed a peak at 3330 cm<sup>1</sup> (stretching of -OH group), 1730 cm<sup>1</sup>

and that the rosin glycerol ester is coated with surrounding PEGylated LBG.

due to the interactions between the functional groups in the blends.

The FTIR spectrum of pure LBG, pure RE, and PEG-LBG/RE PNPs.

DOI: http://dx.doi.org/10.5772/intechopen.90248

3.2 FTIR analysis

3.3 STEM analysis

of it (Figure 9).

11

Figure 8.

Figure 8.

#### 3.1.3 The voluminosity, shape factor, and miscibility parameter

In this study, we investigated the relationship between the intrinsic viscosity and the surface morphology, particle size, and shape. The shape factor was calculated using the approach given as follows: (a) n < 2.5 indicates spherical shape, and (b) n > 2.5 indicates ellipsoidal particles [40].

Figure 7. Plots of [η] of PEG-LBG/RE PNPs at different sonication times (30% amp., 25°C).

The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles DOI: http://dx.doi.org/10.5772/intechopen.90248

Figure 8. The FTIR spectrum of pure LBG, pure RE, and PEG-LBG/RE PNPs.

In this study, we predicted the size and shape factor of PEG-LBG (1:1), PEG-LBG/RE PNPs (1:1), and PEG-LBG/RE PNPs (1:2) using the values of the intrinsic viscosity, associated with the shape factor, which were used to determine the change in the structure configuration. We calculated the shape and the Krigbaum and Wall (Δb) parameters of PEG-LBG/RE PNPs (1:1) using the intrinsic viscosity to determine the changes in the blends. We found that PEG-LBG/RE PNPs (1:1) had a spherical-like configuration, and the amounts of PEG had a role on the miscibility due to the interactions between the functional groups in the blends.

#### 3.2 FTIR analysis

The pH values of the solutions (LBG, PEG-LBG, and PEG-LBG/RE PNPs) at initial pH in KOH, NaOH, and CTAB salt additions were determined: pHinitial, 5.7; pHinitial, 5.55; and pHinitial, 5.32, respectively. In the presence of salt, the values of the intrinsic viscosity for the mixture were observed to change in two different salts such as KOH (pHfinal: 5.93) and NaOH (pHfinal: 5.72). The [η] values for PEG-LBG/ RE PNPs (1:1) did not exhibit distinctive changes in the presence of CTAB (pHfinal: 3.87). Jiang et al. [38] reported that the interactions between blends were dependent on the ionic strength at low salt concentration which was related to the increase of salt concentration. Consequently the addition of NaOH and KOH showed the electrostatic repulsion between charges along the backbone of the polymer blends.

The intrinsic viscosity decreased when the temperature increased, and the relation of the experimental results of PEG-LBG/RE PNPs with the temperature was

In this study, we investigated the relationship between the intrinsic viscosity and the surface morphology, particle size, and shape. The shape factor was calculated using the approach given as follows: (a) n < 2.5 indicates spherical shape, and (b)

However, when PEG-LBG/RE PNPs were sonicated, the intrinsic viscosity decreased for 30 minutes but remained constant after a period of time. These results had proven that the sonication time changed the value of viscosity and was effective on the blends (30% amp., 25°C) (Figure 7). The viscosity of Cu-ethylene glycol (EG) nanofluids was proven to decrease with the sonication time [39]. In this study, we found a similar situation, and demonstrated that sonication time changes the

viscosity, which has a role on the formation of nanoparticles.

3.1.3 The voluminosity, shape factor, and miscibility parameter

Plots of [η] of PEG-LBG/RE PNPs at different sonication times (30% amp., 25°C).

3.1.2 Temperature and sonication time factor

Colloid Science in Pharmaceutical Nanotechnology

n > 2.5 indicates ellipsoidal particles [40].

shown in Figure 6.

Figure 7.

10

The FTIR spectra of pure LBG, pure RE, and PEG-LBG/RE PNPs were shown in Figure 8.

The FTIR spectrum of pure LBG showed a broad absorption peak at 3250 cm<sup>1</sup> (stretching of -OH group), 2952 cm<sup>1</sup> (stretching of –CH), 1748 cm<sup>1</sup> (stretching of C=O), and 1000–1100 cm<sup>1</sup> (stretching of C-O-H). Upadhyay et al. [41] and Chakravorty et al. [42] found the FTIR spectrum data similar. The FTIR spectrum of pure RE showed a peak at 3330 cm<sup>1</sup> (stretching of -OH group), 1730 cm<sup>1</sup> (stretching of C=O), and 1120 cm<sup>1</sup> (stretching of C-O-H). As we have seen from the FTIR results, we have demonstrated that the apparent OH peak of LBG disappeared and that the rosin glycerol ester is coated with surrounding PEGylated LBG.

#### 3.3 STEM analysis

According to the STEM image of PEG-LBG/RE PNPs (160.000x and 300.000x), we can see that the interior structure of the polymeric nanoparticle is LBG with the size lower than 50 nm. We are able to tell that these particles are small agglomerates of it (Figure 9).

PEG-LBG/RE PNPs can be used to increase the therapeutic efficacy and biocom-

The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles

The authors acknowledge the STEM and FTIR analysis support from Arel POTKAM (Istanbul, Turkey), Zeynep Akça, Demet SEZGİN MANSUROGLU, and

patibility of the nanodrug in pharmaceutical and biomedical studies.

Acknowledgements

DOI: http://dx.doi.org/10.5772/intechopen.90248

Deniz ISMIK.

Author details

Selcan Karakus<sup>1</sup>

Turkey

13

and Ayben Kilislioglu<sup>1</sup>

\*, Merve Ilgar<sup>1</sup>

Center, Istanbul Arel University, Istanbul, Turkey

\*Address all correspondence to: selcan@istanbul.edu.tr

University-Cerrahpasa, Istanbul, Turkey

Istanbul Arel University, Istanbul, Turkey

provided the original work is properly cited.

, Ezgi Tan<sup>1</sup>

2 ArelPOTKAM, Polymer Technologies and Composite Application and Research

3 Department of Biomedical Engineering, Faculty of Engineering and Architecture,

4 Department of Electrical-Electronics Engineering, Maltepe University, Istanbul,

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

1 Department of Chemistry, Faculty of Engineering, Istanbul

, Yeşim Müge Sahin2,3, Nevin Tasaltin4

Figure 9.

STEM image of PEG-LBG/RE PNPs (160.000x and 300.000x).

#### 4. Conclusions

We prepared the novel PEG-LBG/RE PNPs with an average particle size of 100 nm using the ultrasonic irradiation. We dispersed the amphiphilic RE coated with PEG-LBG blends in nanosize and spherical structure. We focused on the miscibility of the blends, and shapes of the polymeric nanoparticles were calculated using the values of the intrinsic viscosity in different conditions. We estimate that

The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles DOI: http://dx.doi.org/10.5772/intechopen.90248

PEG-LBG/RE PNPs can be used to increase the therapeutic efficacy and biocompatibility of the nanodrug in pharmaceutical and biomedical studies.

#### Acknowledgements

The authors acknowledge the STEM and FTIR analysis support from Arel POTKAM (Istanbul, Turkey), Zeynep Akça, Demet SEZGİN MANSUROGLU, and Deniz ISMIK.

#### Author details

Selcan Karakus<sup>1</sup> \*, Merve Ilgar<sup>1</sup> , Ezgi Tan<sup>1</sup> , Yeşim Müge Sahin2,3, Nevin Tasaltin4 and Ayben Kilislioglu<sup>1</sup>

1 Department of Chemistry, Faculty of Engineering, Istanbul University-Cerrahpasa, Istanbul, Turkey

2 ArelPOTKAM, Polymer Technologies and Composite Application and Research Center, Istanbul Arel University, Istanbul, Turkey

3 Department of Biomedical Engineering, Faculty of Engineering and Architecture, Istanbul Arel University, Istanbul, Turkey

4 Department of Electrical-Electronics Engineering, Maltepe University, Istanbul, Turkey

\*Address all correspondence to: selcan@istanbul.edu.tr

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

4. Conclusions

STEM image of PEG-LBG/RE PNPs (160.000x and 300.000x).

Colloid Science in Pharmaceutical Nanotechnology

Figure 9.

12

We prepared the novel PEG-LBG/RE PNPs with an average particle size of 100 nm using the ultrasonic irradiation. We dispersed the amphiphilic RE coated with PEG-LBG blends in nanosize and spherical structure. We focused on the miscibility of the blends, and shapes of the polymeric nanoparticles were calculated using the values of the intrinsic viscosity in different conditions. We estimate that

### References

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[3] Petry R, Saboia VM, Franqui LS, Holanda CA, Garcia TR, de Farias G, et al. On the formation of protein corona on colloidal nanoparticles stabilized by depletant polymers. Materials Science and Engineering: C.18. 2019;105:1-12

[4] Behnajady MA, Eskandarloo H, Modirshahla N, Shokri M. Sol-gel low temperature synthesis of stable anatase type TiO2 nanoparticles under different conditions and its photocatalytic activity. Photochemistry and Photobiology. 2011;87(5):1002-1008

[5] Henglein A. Colloidal silver nanoparticles: Photochemical preparation and interaction with O2, CCl4, and some metal ions. Chemistry of Materials. 1998;10(1):444-450

[6] Cabrera L, Gutierrez S, Menendez N, Morales MP, Herrasti P. Magnetite nanoparticles: Electrochemical synthesis and characterization. Electrochimica Acta. 2008;53(8):3436-3441

[7] Im HJ, Jung EC. Colloidal nanoparticles produced from Cu metal in water by laser ablation and their agglomeration. Radiation Physics and Chemistry. 2016;118:6-10

[8] Gasaymeh SS, Radiman S, Heng LY, Saion E, Saeed GM. Synthesis and characterization of silver/ polyvinilpirrolidone (Ag/PVP) nanoparticles using gamma irradiation

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DOI: http://dx.doi.org/10.5772/intechopen.90248

nanocomposite derived from cationically modified guar gum and silica nanoparticles. Journal of

The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles

stabilized gold nanoparticles: Characterization, biocompatibility, stability and cytotoxicity. Carbohydrate

Polymers. 2014;110:1-9

2017;96:786-797

336-344

Hazardous Materials. 2016;301:127-136

[24] Pooja D, Panyaram S, Kulhari H, Rachamalla SS, Sistla R. Xanthan gum

[25] Braz L, Grenha A, Ferreira D, da Costa AMR, Gamazo C, Sarmento B. Chitosan/sulfated locust bean gum nanoparticles: In vitro and in vivo evaluation towards an application in oral immunization. International Journal of Biological Macromolecules.

[26] Pawar HA, Lalitha KG, Ruckmani K.

Costa AMR, Belo JA. Locust bean gum as an alternative polymeric coating for embryonic stem cell culture. Materials Science and Engineering: C. 2014;40:

[28] Higiro J, Herald TJ, Alavi S, Bean S. Rheological study of xanthan and locust bean gum interaction in dilute solution:

Effect of salt. Food Research International. 2007;40(4):435-447

[29] Cordeiro T, Paninho AB, Bernardo M, Matos I, Pereira CV, Serra AT, et al. Biocompatible locust bean gum as mesoporous carriers for naproxen delivery. Materials Chemistry

and Physics. 2020;239:121973

[30] Braz L, Grenha A, Corvo MC, Lourenco JP, Ferreira D, Sarmento B, et al. Synthesis and characterization of locust bean gum derivatives and their

Alginate beads of captopril using galactomannan containing Senna tora gum, guar gum and locust bean gum. International Journal of Biological Macromolecules. 2015;76:119-131

[27] Perestrelo AR, Grenha A, da

[17] Karakus S, Ilgar M, Kahyaoglu IM, Kilislioglu A. Influence of ultrasound irradiation on the intrinsic viscosity of guar gum–PEG/rosin glycerol ester nanoparticles. International Journal of Biological Macromolecules. 2019;141:

[18] Barak S, Mudgil D. Locust bean gum: Processing, properties and food applications—A review. International Journal of Biological Macromolecules.

[19] Jayapal JJ, Dhanaraj S. Exemestane loaded alginate nanoparticles for cancer treatment: Formulation and in vitro evaluation. International Journal of Biological Macromolecules. 2017;105:

[20] Yu S, Xu X, Feng J, Liu M, Hu K. Chitosan and chitosan coating

disease. International Journal of Pharmaceutics. 2019;560:282-293

[21] Sethi S, Kaith BS, Kumar V. Fabrication and characterization of microwave assisted carboxymethyl cellulose-gelatin silver nanoparticles imbibed hydrogel: Its evaluation as dye degradation. Reactive and Functional

Polymers. 2019;142:134-146

[22] Şişmanoğlu T, Karakuş S, Birer Ö, Soylu GSP, Kolan A, Tan E, et al. Preparation and characterization of antibacterial Senegalia (Acacia)

Senegal/iron–silica bio-nanocomposites. Applied Surface Science. 2015;354:

[23] Patra AS, Ghorai S, Ghosh S, Mandal B, Pal S. Selective removal of toxic anionic dyes using a novel

nanoparticles for the treatment of brain

2019;160:130-142

1118-1127

2014;66:74-80

416-421

250-255

15

[9] Tan E, Karakus S, Soylu GSP, Birer Ö, Zengin Y, Kilislioglu A. Formation and distribution of ZnO nanoparticles and its effect on E. coli in the presence of sepiolite and silica within the chitosan matrix via sonochemistry. Ultrasonics Sonochemistry. 2017;38:720-725

[10] Gong C, Hart DP. Ultrasound induced cavitation and sonochemical yields. The Journal of the Acoustical Society of America. 1998;104(5):2675-2682

[11] Cui D, Mebel AM, Arroyo-Mora LE, Holness H, Furton KG, O'Shea K. Kinetic, product, and computational studies of the ultrasonic induced degradation of 4 methylcyclohexanemethanol (MCHM). Water Research. 2017;126:164-171

[12] Masoudian N, Rajabi M, Ghaedi M. Titanium oxide nanoparticles loaded onto activated carbon prepared from bio-waste watermelon rind for the efficient ultrasonic-assisted adsorption of Congo red and phenol red dyes from wastewaters. Polyhedron. 2019;173:1-9

[13] Karakuş S. Preparation and rheological characterization of Chitosan-Gelatine@ ZnO-Si nanoparticles. International Journal of Biological Macromolecules. 2019;137:821-828

[14] Boufi S, Haaj SB, Magnin A, Pignon F, Impéror-Clerc M, Mortha G. Ultrasonic assisted production of starch nanoparticles: Structural characterization and mechanism of disintegration. Ultrasonics Sonochemistry. 2018;41:327-336

[15] Sabaghi V, Davar F, Taherian MH. Ultrasonic-assisted preparation of AlON from alumina/carbon core-shell nanoparticle. Ceramics International. 2019;45(3):3350-3358

The Viscosity Behaviour of PEGylated Locust Bean Gum/Rosin Ester Polymeric Nanoparticles DOI: http://dx.doi.org/10.5772/intechopen.90248

[16] Dave V, Tak K, Sohgaura A, Gupta A, Sadhu V, Reddy KR. Lipidpolymer hybrid nanoparticles: Synthesis strategies and biomedical applications. Journal of Microbiological Methods. 2019;160:130-142

References

2002;54(3):281-284

2002;2(1):1-24

2019;105:1-12

[1] Montasser I, Fessi H, Coleman AW. Atomic force microscopy imaging of novel type of polymeric colloidal nanostructures. European Journal of Pharmaceutics and Biopharmaceutics.

Colloid Science in Pharmaceutical Nanotechnology

techniques. The African Review of

[9] Tan E, Karakus S, Soylu GSP, Birer Ö, Zengin Y, Kilislioglu A. Formation and distribution of ZnO nanoparticles and its effect on E. coli in the presence of sepiolite and silica within the chitosan matrix via sonochemistry. Ultrasonics Sonochemistry. 2017;38:720-725

[10] Gong C, Hart DP. Ultrasound induced cavitation and sonochemical yields. The Journal of the Acoustical Society of America. 1998;104(5):2675-2682

[11] Cui D, Mebel AM, Arroyo-Mora LE, Holness H, Furton KG, O'Shea K. Kinetic, product, and computational studies of the ultrasonic induced degradation of 4 methylcyclohexanemethanol (MCHM). Water Research. 2017;126:164-171

[12] Masoudian N, Rajabi M, Ghaedi M. Titanium oxide nanoparticles loaded onto activated carbon prepared from bio-waste watermelon rind for the efficient ultrasonic-assisted adsorption of Congo red and phenol red dyes from wastewaters. Polyhedron. 2019;173:1-9

[13] Karakuş S. Preparation and

Gelatine@ ZnO-Si nanoparticles. International Journal of Biological Macromolecules. 2019;137:821-828

[14] Boufi S, Haaj SB, Magnin A, Pignon F, Impéror-Clerc M, Mortha G. Ultrasonic assisted production of starch

characterization and mechanism of

[15] Sabaghi V, Davar F, Taherian MH. Ultrasonic-assisted preparation of AlON

from alumina/carbon core-shell nanoparticle. Ceramics International.

2019;45(3):3350-3358

nanoparticles: Structural

disintegration. Ultrasonics Sonochemistry. 2018;41:327-336

rheological characterization of Chitosan-

Physics. 2010;4:31-41

[2] Bourgeat-Lami E. Organic–inorganic nanostructured colloids. Journal of Nanoscience and Nanotechnology.

[3] Petry R, Saboia VM, Franqui LS, Holanda CA, Garcia TR, de Farias G, et al. On the formation of protein corona on colloidal nanoparticles stabilized by depletant polymers. Materials Science and Engineering: C.18.

[4] Behnajady MA, Eskandarloo H, Modirshahla N, Shokri M. Sol-gel low temperature synthesis of stable anatase type TiO2 nanoparticles under different conditions and its photocatalytic activity. Photochemistry and

Photobiology. 2011;87(5):1002-1008

preparation and interaction with O2, CCl4, and some metal ions. Chemistry of

[6] Cabrera L, Gutierrez S, Menendez N, Morales MP, Herrasti P. Magnetite nanoparticles: Electrochemical synthesis and characterization. Electrochimica

nanoparticles produced from Cu metal in water by laser ablation and their agglomeration. Radiation Physics and

[8] Gasaymeh SS, Radiman S, Heng LY, Saion E, Saeed GM. Synthesis and

nanoparticles using gamma irradiation

[5] Henglein A. Colloidal silver nanoparticles: Photochemical

Materials. 1998;10(1):444-450

Acta. 2008;53(8):3436-3441

[7] Im HJ, Jung EC. Colloidal

Chemistry. 2016;118:6-10

characterization of silver/ polyvinilpirrolidone (Ag/PVP)

14

[17] Karakus S, Ilgar M, Kahyaoglu IM, Kilislioglu A. Influence of ultrasound irradiation on the intrinsic viscosity of guar gum–PEG/rosin glycerol ester nanoparticles. International Journal of Biological Macromolecules. 2019;141: 1118-1127

[18] Barak S, Mudgil D. Locust bean gum: Processing, properties and food applications—A review. International Journal of Biological Macromolecules. 2014;66:74-80

[19] Jayapal JJ, Dhanaraj S. Exemestane loaded alginate nanoparticles for cancer treatment: Formulation and in vitro evaluation. International Journal of Biological Macromolecules. 2017;105: 416-421

[20] Yu S, Xu X, Feng J, Liu M, Hu K. Chitosan and chitosan coating nanoparticles for the treatment of brain disease. International Journal of Pharmaceutics. 2019;560:282-293

[21] Sethi S, Kaith BS, Kumar V. Fabrication and characterization of microwave assisted carboxymethyl cellulose-gelatin silver nanoparticles imbibed hydrogel: Its evaluation as dye degradation. Reactive and Functional Polymers. 2019;142:134-146

[22] Şişmanoğlu T, Karakuş S, Birer Ö, Soylu GSP, Kolan A, Tan E, et al. Preparation and characterization of antibacterial Senegalia (Acacia) Senegal/iron–silica bio-nanocomposites. Applied Surface Science. 2015;354: 250-255

[23] Patra AS, Ghorai S, Ghosh S, Mandal B, Pal S. Selective removal of toxic anionic dyes using a novel

nanocomposite derived from cationically modified guar gum and silica nanoparticles. Journal of Hazardous Materials. 2016;301:127-136

[24] Pooja D, Panyaram S, Kulhari H, Rachamalla SS, Sistla R. Xanthan gum stabilized gold nanoparticles: Characterization, biocompatibility, stability and cytotoxicity. Carbohydrate Polymers. 2014;110:1-9

[25] Braz L, Grenha A, Ferreira D, da Costa AMR, Gamazo C, Sarmento B. Chitosan/sulfated locust bean gum nanoparticles: In vitro and in vivo evaluation towards an application in oral immunization. International Journal of Biological Macromolecules. 2017;96:786-797

[26] Pawar HA, Lalitha KG, Ruckmani K. Alginate beads of captopril using galactomannan containing Senna tora gum, guar gum and locust bean gum. International Journal of Biological Macromolecules. 2015;76:119-131

[27] Perestrelo AR, Grenha A, da Costa AMR, Belo JA. Locust bean gum as an alternative polymeric coating for embryonic stem cell culture. Materials Science and Engineering: C. 2014;40: 336-344

[28] Higiro J, Herald TJ, Alavi S, Bean S. Rheological study of xanthan and locust bean gum interaction in dilute solution: Effect of salt. Food Research International. 2007;40(4):435-447

[29] Cordeiro T, Paninho AB, Bernardo M, Matos I, Pereira CV, Serra AT, et al. Biocompatible locust bean gum as mesoporous carriers for naproxen delivery. Materials Chemistry and Physics. 2020;239:121973

[30] Braz L, Grenha A, Corvo MC, Lourenco JP, Ferreira D, Sarmento B, et al. Synthesis and characterization of locust bean gum derivatives and their

application in the production of nanoparticles. Carbohydrate Polymers. 2018;181:974-985

[31] Soumya RS, Sherin S, Raghu KG, Abraham A. Allicin functionalized locust bean gum nanoparticles for improved therapeutic efficacy: An in silico, in vitro and in vivo approach. International Journal of Biological Macromolecules. 2018;109:740-747

[32] Behrouzian F, Razavi SM, Karazhiyan H. Intrinsic viscosity of cress (Lepidium sativum) seed gum: Effect of salts and sugars. Food Hydrocolloids. 2014;35:100-105

[33] Huggins ML. The viscosity of dilute solutions of long-chain molecules. IV. Dependence on concentration. Journal of the American Chemical Society. 1942; 64(11):2716-2718

[34] Kraemer EO. Molecular weights of cellulose and cellulose derivatives. Industrial & Engineering Chemistry. 1938;30(10):1200-1203

[35] Tanglertpaibul T, Rao MA. Intrinsic viscosity of tomato serum as affected by methods of determination and methods of processing concentrates. Journal of Food Science. 1987;52(6):1642-1645

[36] Chen HH, Kang HY, Chen SD. The effects of ingredients and water content on the rheological properties of batters and physical properties of crusts in fried foods. Journal of Food Engineering. 2008;88(1):45-54

[37] Razavi SM, Moghaddam TM, Emadzadeh B, Salehi F. Dilute solution properties of wild sage (Salvia macrosiphon) seed gum. Food Hydrocolloids. 2012;29(1):205-210

[38] Jiang WH, Han SJ. The interactions of chitosan–poly (ethylene glycol) in the presence of added salt in water: Viscosity effect. European Polymer Journal. 1999;35(11):2079-2085

[39] Li F, Li L, Zhong G, Zhai Y, Li Z. Effects of ultrasonic time, size of aggregates and temperature on the stability and viscosity of Cu-ethylene glycol (EG) nanofluids. International Journal of Heat and Mass Transfer. 2019;129:278-286

[40] Curvale R, Masuelli M, Padilla AP. Intrinsic viscosity of bovine serum albumin conformers. International Journal of Biological Macromolecules. 2008;42(2):133-137

[41] Upadhyay M, Adena SKR, Vardhan H, Yadav SK, Mishra B. Locust bean gum and sodium alginate based interpenetrating polymeric network microbeads encapsulating Capecitabine: Improved pharmacokinetics, cytotoxicity &in vivo antitumor activity. Materials Science and Engineering: C. 2019;104:109958

[42] Chakravorty A, Barman G, Mukherjee S, Sa B. Effect of carboxymethylation on rheological and drug release characteristics of locust bean gum matrix tablets. Carbohydrate Polymers. 2016;144:50-58

**17**

diagnosis and treatment.

**Chapter 2**

**Abstract**

**1. Introduction**

Magnetic and Quantum Dot

and Diagnostic Systems

different methods of drug delivery will be addressed.

**Keywords:** drug delivery, quantum dots, magnetic nanoparticles

Among many synthetic compounds the general public comes across with, in day-to-day life, nanoparticles are considered highly advantageous in various applications. Nanoparticles in diagnostics and as drug delivery vehicles are coming under the aforementioned beneficial applications in the field of biomedical science. Various types of nanoparticles, for instance, gold nanoparticles [1] and iron oxide nanoparticles [2], are being used in biomedical operations. Due to its magnetic properties and nanometer size, magnetic nanoparticles such as magnetite (Fe3O4) [3] and maghemite (γ-Fe2O3) [4, 5] are considered highly beneficial for diagnostics and in drug delivery systems. On the other hand, inorganic nanoscale particles with semiconductor properties are becoming very popular in such applications. These semiconductor nanoparticles, called quantum dot nanoparticles, are equipped with extremely favorable characteristics such as high fluorescence and photoluminescence. These nanoparticles have been tested to be used in diagnostics [6], and trials were carried out at laboratory scale as therapeutics, that is, for drug delivery [7]. At the same time, quantum dots are found to be more beneficial over regular chemotherapy, radiation, and ionizing radiation imaging [8] which are used in cancer

*and Lakmal Jayarathne*

*Erandi Munasinghe, Maheshi Aththapaththu* 

Nanoparticles for Drug Delivery

Nanoparticles are being used tremendously in biomedical sciences due to their promising chemical and physical properties. Magnetic nanoparticles and quantum dot nanocrystals are two of the main nanoparticle types used in the biomedical industry. The surface of these nanoparticles is further modified in order to obtain biocompatibility and surface functionalization. Magnetic properties, fluorescence, nanometer size, and availability of sites to modify its surface for bioconjugation provide greater potential to use these nanoparticles in targeted drug delivery technique and diagnostics. As a result, these nanoparticles create massive developments in the industrial operations. In this chapter, an overview of the nanoparticles used in drug delivery and diagnostic systems will be discussed. In addition, advantages in encapsulation of magnetic and quantum dot nanoparticles for bioconjugation and

#### **Chapter 2**

application in the production of nanoparticles. Carbohydrate Polymers.

[32] Behrouzian F, Razavi SM, Karazhiyan H. Intrinsic viscosity of cress (Lepidium sativum) seed gum: Effect of salts and sugars. Food Hydrocolloids. 2014;35:100-105

[33] Huggins ML. The viscosity of dilute solutions of long-chain molecules. IV. Dependence on concentration. Journal of the American Chemical Society. 1942;

[34] Kraemer EO. Molecular weights of cellulose and cellulose derivatives. Industrial & Engineering Chemistry.

[35] Tanglertpaibul T, Rao MA. Intrinsic viscosity of tomato serum as affected by methods of determination and methods of processing concentrates. Journal of Food Science. 1987;52(6):1642-1645

[36] Chen HH, Kang HY, Chen SD. The effects of ingredients and water content on the rheological properties of batters and physical properties of crusts in fried foods. Journal of Food Engineering.

[37] Razavi SM, Moghaddam TM, Emadzadeh B, Salehi F. Dilute solution

[38] Jiang WH, Han SJ. The interactions of chitosan–poly (ethylene glycol) in the

properties of wild sage (Salvia macrosiphon) seed gum. Food Hydrocolloids. 2012;29(1):205-210

presence of added salt in water: Viscosity effect. European Polymer Journal. 1999;35(11):2079-2085

[31] Soumya RS, Sherin S, Raghu KG, Abraham A. Allicin functionalized locust bean gum nanoparticles for improved therapeutic efficacy: An in silico, in vitro and in vivo approach. International Journal of Biological Macromolecules. 2018;109:740-747

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[39] Li F, Li L, Zhong G, Zhai Y, Li Z. Effects of ultrasonic time, size of aggregates and temperature on the stability and viscosity of Cu-ethylene glycol (EG) nanofluids. International Journal of Heat and Mass Transfer.

[40] Curvale R, Masuelli M, Padilla AP. Intrinsic viscosity of bovine serum albumin conformers. International Journal of Biological Macromolecules.

Vardhan H, Yadav SK, Mishra B. Locust bean gum and sodium alginate based interpenetrating polymeric network microbeads encapsulating Capecitabine:

2019;129:278-286

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[41] Upadhyay M, Adena SKR,

Improved pharmacokinetics, cytotoxicity &in vivo antitumor activity. Materials Science and Engineering: C. 2019;104:109958

[42] Chakravorty A, Barman G, Mukherjee S, Sa B. Effect of

Polymers. 2016;144:50-58

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16

1938;30(10):1200-1203

## Magnetic and Quantum Dot Nanoparticles for Drug Delivery and Diagnostic Systems

*Erandi Munasinghe, Maheshi Aththapaththu and Lakmal Jayarathne*

#### **Abstract**

Nanoparticles are being used tremendously in biomedical sciences due to their promising chemical and physical properties. Magnetic nanoparticles and quantum dot nanocrystals are two of the main nanoparticle types used in the biomedical industry. The surface of these nanoparticles is further modified in order to obtain biocompatibility and surface functionalization. Magnetic properties, fluorescence, nanometer size, and availability of sites to modify its surface for bioconjugation provide greater potential to use these nanoparticles in targeted drug delivery technique and diagnostics. As a result, these nanoparticles create massive developments in the industrial operations. In this chapter, an overview of the nanoparticles used in drug delivery and diagnostic systems will be discussed. In addition, advantages in encapsulation of magnetic and quantum dot nanoparticles for bioconjugation and different methods of drug delivery will be addressed.

**Keywords:** drug delivery, quantum dots, magnetic nanoparticles

#### **1. Introduction**

Among many synthetic compounds the general public comes across with, in day-to-day life, nanoparticles are considered highly advantageous in various applications. Nanoparticles in diagnostics and as drug delivery vehicles are coming under the aforementioned beneficial applications in the field of biomedical science. Various types of nanoparticles, for instance, gold nanoparticles [1] and iron oxide nanoparticles [2], are being used in biomedical operations. Due to its magnetic properties and nanometer size, magnetic nanoparticles such as magnetite (Fe3O4) [3] and maghemite (γ-Fe2O3) [4, 5] are considered highly beneficial for diagnostics and in drug delivery systems. On the other hand, inorganic nanoscale particles with semiconductor properties are becoming very popular in such applications. These semiconductor nanoparticles, called quantum dot nanoparticles, are equipped with extremely favorable characteristics such as high fluorescence and photoluminescence. These nanoparticles have been tested to be used in diagnostics [6], and trials were carried out at laboratory scale as therapeutics, that is, for drug delivery [7]. At the same time, quantum dots are found to be more beneficial over regular chemotherapy, radiation, and ionizing radiation imaging [8] which are used in cancer diagnosis and treatment.

#### **2. Nanoparticles used in drug delivery and diagnostic systems**

#### **2.1 Magnetic nanoparticles**

Magnetic nanoparticles are used widely in a variety of industrial applications in environmental remediation [9], data storage [10], electronic device development [11], and pharmaceutical industry [12, 13]. Its magnetic properties give a greater potential in delivering the drugs at desired sites. The nanoscale size of the particles gives the ability to permeate through membranes without the interference of biological barriers. Therefore, the so-called properties make magnetic nanoparticles an ineluctable component in the development of drug delivery systems.

#### *2.1.1 Properties of magnetic nanoparticles*

Several types of magnetic nanoparticles such as iron, nickel, and cobalt based are available for industrial applications [14]. Due to the greater potential in surface modification and higher magnetic properties, iron oxide nanoparticles are considered as the best magnetic candidate in the development of drug delivery systems. These single-domain iron oxide magnetic nanoparticles are present in three different phases, as magnetite, maghemite, and hematite (α-Fe2O3) [15]. These nanoparticles generally demonstrate super-paramagnetic properties at ambient conditions even though their physical and chemical properties largely depend on the synthesis procedure and particle size [16]. According to the motions and interactions of the electrons available in the material, magnetism is divided in to five main classes as diamagnetism, paramagnetism, ferrimagnetism, ferromagnetism, and antiferromagnetism [17, 18]. Iron oxide nanoparticles fall under ferromagnetic and ferromagnetic classes due to their strong collective magnetic interaction [18].

To be used in a biological environment, there are several concerns that the magnetic nanoparticles should conquer. Colloidal and chemical stability of these particles is the main consideration. The stability of magnetic nanoparticles is extremely affected by intrinsic structural properties such as size, morphology, and pH of the particles [19].

#### *2.1.2 Synthesis of magnetic nanoparticles*

Synthesis of iron oxide nanoparticles can be conducted in different procedures using physical, chemical, or biological methods [18]. Chemical methods such as coprecipitation, hydrothermal reactions, thermal decomposition, microemulsion, sol-gel reactions, aerosol/vapor phase method, and electrochemical method are the principal preparation procedures. These procedures have the ability to control particle size, surface chemistry, and composition. Most simple, efficient, and cost-effective methods among these procedures are coprecipitation and thermal decomposition, which are also used widely due to the same reasons. In coprecipitation, metal oxide particles are synthesized using a solution of the metal salt. In the synthesis of iron oxide nanoparticles, aqueous Fe3+ and Fe2+ are coprecipitated by addition of a base, preferably, sodium hydroxide or ammonium [18].

#### *2.1.3 Biomedical applications*

As a result of its nanometer size, as small as 3 nm [20], magnetic nanoparticles can reach the biological entities according to the interest. Cells with 10–100 μm size, proteins as large as 5–50 nm or even genes which can be 2 nm wide and 10–100 nm long, or viruses with size ranging from 20 to 450 nm can be targeted using these

**19**

*Magnetic and Quantum Dot Nanoparticles for Drug Delivery and Diagnostic Systems*

tissue engineering [27], magnetic particle imaging (MPI) [28], etc.

quantum dots more beneficial in industrial and biomedical operations.

These nanocrystals display fluorescence and produce distinctive colors which

As presented in **Figure 1**, there are several types of quantum dots as core type [38], core-shell type [39], and alloyed type (bimetallic) [40], which are classified based on their composition and structure. Core-type quantum dots contain single component inorganic core and can be chalcogenides of metals such as PbS, CdTe, CdSe, etc. [38]. These can be further modified with another layer around the core using many substances, according to the application's requirement. Typically, in biomedical applications, these core structures are stabilized with an organic layer around the core in order to obtain a hydrophobic or hydrophilic surface. The electroluminescent and photoluminescent properties of these core-type quantum

can be determined by the nanocrystal particle size. Fluorescence is a form of luminescence, where a substance absorbs light or other electromagnetic radiation and emits light of a longer wavelength than the absorbed light [34]. In general, luminescence is defined as the emission of photons from the excited electronic state. In contrast, when the atoms of the material absorb energy, these atoms are in the excited state. These excited atoms release absorbed energy as photons, which ultimately discharge light [35]. These quantum dot nanoparticles exhibit extraordi-

nary photoluminescence with increased brightness and stability [36, 37].

dots can be refined by basically altering the crystal size [12].

*2.2.1 Properties of quantum dot nanoparticles*

magnetic nanoparticles [21]. The property of magnetism, where these nanoparticles can be manipulated by an external magnetic field, enhances its utility by providing the ability to get these nanoparticles to where they are required. Magnetic nanoparticles are used in various applications in the aspects of biomedicine and biology. Magnetic separation has been of greater advantage in biological research, where magnetic nanoparticles are labeled to desired biological substances. These have proven superior sensitivity in cell sorting especially in immuno-magnetic selection of rare tumor cells in blood [22]. Moreover, these magnetic nanoparticles are used in a vast number of biological operations such as targeted drug delivery [23], hyperthermia [24], magnetic resonance imaging (MRI) [25], rapid diagnostics [26],

Quantum dot nanocrystals are semiconductor nanomaterials with intrinsic chemical and physical properties. These have unique semiconductor energy levels that can be adopted by simply changing size, shape, and charge potential [29]. In quantum dot nanoparticles, excitons are confined in all three dimensions. Quantum confinement is a property of semiconductors where the diameter of the nanoparticle approaches that of the Bohr exciton radius. These nanoparticles have particular optical and electronic properties such as size-tunable absorption bands and emission colors due to the quantum confinement effect [30]. Quantum dot particles are artificially synthesized from II to IV and III to V elements such as Cd, Te, Se, Zn, etc. [31]. These are nanoscale structures typically with a diameter of 2–10 nm, which make them a more reliable and influential candidate in most of the industrial applications. Due to its small diameter, the surface atom to core atom ratio is high [32]. When the surface atom to core atom ratio increases, the properties of surface atoms dominate the properties of the whole particle. The semiconductor lattice of quantum dots is terminating on the surface, and therefore, the surface atoms show a different chemical behavior than the core atoms [33]. This ultimately makes the

*DOI: http://dx.doi.org/10.5772/intechopen.88611*

**2.2 Quantum dot nanoparticles**

*Magnetic and Quantum Dot Nanoparticles for Drug Delivery and Diagnostic Systems DOI: http://dx.doi.org/10.5772/intechopen.88611*

magnetic nanoparticles [21]. The property of magnetism, where these nanoparticles can be manipulated by an external magnetic field, enhances its utility by providing the ability to get these nanoparticles to where they are required. Magnetic nanoparticles are used in various applications in the aspects of biomedicine and biology. Magnetic separation has been of greater advantage in biological research, where magnetic nanoparticles are labeled to desired biological substances. These have proven superior sensitivity in cell sorting especially in immuno-magnetic selection of rare tumor cells in blood [22]. Moreover, these magnetic nanoparticles are used in a vast number of biological operations such as targeted drug delivery [23], hyperthermia [24], magnetic resonance imaging (MRI) [25], rapid diagnostics [26], tissue engineering [27], magnetic particle imaging (MPI) [28], etc.

#### **2.2 Quantum dot nanoparticles**

*Colloid Science in Pharmaceutical Nanotechnology*

*2.1.1 Properties of magnetic nanoparticles*

**2.1 Magnetic nanoparticles**

pH of the particles [19].

*2.1.3 Biomedical applications*

*2.1.2 Synthesis of magnetic nanoparticles*

**2. Nanoparticles used in drug delivery and diagnostic systems**

an ineluctable component in the development of drug delivery systems.

magnetic classes due to their strong collective magnetic interaction [18].

addition of a base, preferably, sodium hydroxide or ammonium [18].

To be used in a biological environment, there are several concerns that the magnetic nanoparticles should conquer. Colloidal and chemical stability of these particles is the main consideration. The stability of magnetic nanoparticles is extremely affected by intrinsic structural properties such as size, morphology, and

Synthesis of iron oxide nanoparticles can be conducted in different procedures using physical, chemical, or biological methods [18]. Chemical methods such as coprecipitation, hydrothermal reactions, thermal decomposition, microemulsion, sol-gel reactions, aerosol/vapor phase method, and electrochemical method are the principal preparation procedures. These procedures have the ability to control particle size, surface chemistry, and composition. Most simple, efficient, and cost-effective methods among these procedures are coprecipitation and thermal decomposition, which are also used widely due to the same reasons. In coprecipitation, metal oxide particles are synthesized using a solution of the metal salt. In the synthesis of iron oxide nanoparticles, aqueous Fe3+ and Fe2+ are coprecipitated by

As a result of its nanometer size, as small as 3 nm [20], magnetic nanoparticles can reach the biological entities according to the interest. Cells with 10–100 μm size, proteins as large as 5–50 nm or even genes which can be 2 nm wide and 10–100 nm long, or viruses with size ranging from 20 to 450 nm can be targeted using these

Magnetic nanoparticles are used widely in a variety of industrial applications in environmental remediation [9], data storage [10], electronic device development [11], and pharmaceutical industry [12, 13]. Its magnetic properties give a greater potential in delivering the drugs at desired sites. The nanoscale size of the particles gives the ability to permeate through membranes without the interference of

biological barriers. Therefore, the so-called properties make magnetic nanoparticles

Several types of magnetic nanoparticles such as iron, nickel, and cobalt based are available for industrial applications [14]. Due to the greater potential in surface modification and higher magnetic properties, iron oxide nanoparticles are considered as the best magnetic candidate in the development of drug delivery systems. These single-domain iron oxide magnetic nanoparticles are present in three different phases, as magnetite, maghemite, and hematite (α-Fe2O3) [15]. These nanoparticles generally demonstrate super-paramagnetic properties at ambient conditions even though their physical and chemical properties largely depend on the synthesis procedure and particle size [16]. According to the motions and interactions of the electrons available in the material, magnetism is divided in to five main classes as diamagnetism, paramagnetism, ferrimagnetism, ferromagnetism, and antiferromagnetism [17, 18]. Iron oxide nanoparticles fall under ferromagnetic and ferro-

**18**

Quantum dot nanocrystals are semiconductor nanomaterials with intrinsic chemical and physical properties. These have unique semiconductor energy levels that can be adopted by simply changing size, shape, and charge potential [29]. In quantum dot nanoparticles, excitons are confined in all three dimensions. Quantum confinement is a property of semiconductors where the diameter of the nanoparticle approaches that of the Bohr exciton radius. These nanoparticles have particular optical and electronic properties such as size-tunable absorption bands and emission colors due to the quantum confinement effect [30]. Quantum dot particles are artificially synthesized from II to IV and III to V elements such as Cd, Te, Se, Zn, etc. [31]. These are nanoscale structures typically with a diameter of 2–10 nm, which make them a more reliable and influential candidate in most of the industrial applications. Due to its small diameter, the surface atom to core atom ratio is high [32]. When the surface atom to core atom ratio increases, the properties of surface atoms dominate the properties of the whole particle. The semiconductor lattice of quantum dots is terminating on the surface, and therefore, the surface atoms show a different chemical behavior than the core atoms [33]. This ultimately makes the quantum dots more beneficial in industrial and biomedical operations.

#### *2.2.1 Properties of quantum dot nanoparticles*

These nanocrystals display fluorescence and produce distinctive colors which can be determined by the nanocrystal particle size. Fluorescence is a form of luminescence, where a substance absorbs light or other electromagnetic radiation and emits light of a longer wavelength than the absorbed light [34]. In general, luminescence is defined as the emission of photons from the excited electronic state. In contrast, when the atoms of the material absorb energy, these atoms are in the excited state. These excited atoms release absorbed energy as photons, which ultimately discharge light [35]. These quantum dot nanoparticles exhibit extraordinary photoluminescence with increased brightness and stability [36, 37].

As presented in **Figure 1**, there are several types of quantum dots as core type [38], core-shell type [39], and alloyed type (bimetallic) [40], which are classified based on their composition and structure. Core-type quantum dots contain single component inorganic core and can be chalcogenides of metals such as PbS, CdTe, CdSe, etc. [38]. These can be further modified with another layer around the core using many substances, according to the application's requirement. Typically, in biomedical applications, these core structures are stabilized with an organic layer around the core in order to obtain a hydrophobic or hydrophilic surface. The electroluminescent and photoluminescent properties of these core-type quantum dots can be refined by basically altering the crystal size [12].

*Colloid Science in Pharmaceutical Nanotechnology*

#### **Figure 1.**

*Types of quantum dots used in drug delivery [44].*

Core-shell-type quantum dots, such as CdTe/CdSe [41], CdSe/ZnS [42], CdSe/ CdS, etc., are comprised of an inorganic core and an inorganic shell, generally a higher bandgap semiconductor around the core. Core-shell structures of quantum dots are more effective and have an intense brightness, as a result of the diminished chemical damage that can be happened to the fluorescence core. It is believed that inorganic core-shell quantum dots are more robust than organically passivated core-type quantum dots [43].

Alloyed quantum dots are synthesized by alloying two semiconductors with different bandgap energies. This type emits colors by just altering the composition rather than changing the crystallite size as a result of both homogenous and gradient internal structures [44].

#### *2.2.2 Synthesis of quantum dots*

Among several methods utilized to synthesis quantum dots, hydrothermal synthesis [45, 46], and organometallic synthesis [47, 48] are the mainly used two techniques. Other methods, for instance, polyol-hydrolysis [49], electron beam irradiation [50], microwave-assisted aqueous synthesis [51], photochemical synthesis [52], UV irradiation [53], and chemical precipitation [54], are also less commonly used for quantum dot synthesis. CdTe quantum dots are highly used in biomedical applications compared to other types of quantum dots. Generally, CdTe quantum dots demonstrate inferior biocompatibility and stability in biological systems. Therefore, methods have developed to modify the surface of CdTe quantum dots during synthesis by capping the quantum dots using different stabilizers such as trioctylphosphine (TOP)/trioctylphosphine oxide (TOPO) [55], etc. Particularly, quantum dots which are capped with stabilizers containing thiol groups [56] make the quantum dots highly biocompatible and more stable inside biological environment [57, 58]. The CdTe quantum dots, which are synthesized in aqueous medium using thioglycolic acid [59], cysteine [60], and glutathione [61], provide high luminescence, stability, and surface functionalization to conjugate biomolecules.

#### *2.2.3 Biomedical application*

Recently, quantum dots are used in many biotechnological appliances [6, 62]. These fluorescent nanocrystals are utilized in many immunofluorescence assays [63], tissue engineering [64], DNA array technology [65], and other cell biology techniques [66] where fluorescence measurements are occupied. Single-molecule level studies of living cells [67] and targeted drug delivery for cancer treatment [68] are some other applications in medicine. There are many advantages of using

**21**

rolidone (PVP) [81].

**4. Different methods of drug delivery**

*Magnetic and Quantum Dot Nanoparticles for Drug Delivery and Diagnostic Systems*

quantum dots in biotechnology. As the fluorescence of quantum dots is intense than other conventional dyes classically used in immuno-labeling and staining of proteins, quantum dots are currently being used in immunoassays as fluorophores

**3. Advantages and advances in encapsulation of nanoparticles for** 

Bare nanoparticles often show undesirable properties in biological systems. These nanoparticles are often hydrophobic or hydrophilic, susceptible to oxidation and agglomeration. The main concern with magnetic nanoparticles is that they may fail to exhibit their super-paramagnetic properties inside or when conjugated to biological systems. This reduction of magnetism occurs as a consequence of their high chemical reactivity and extraordinary surface energy [16]. With the intention of maintaining nanoparticles in the colloidal condition during storage and to increase their constancy and biocompatibility, bare nanoparticles are further modified. Generally, surface modification is performed using polymers or surfactants which are hefty or charged molecules compared to the nanoparticles. These modifications provide several advantages such as increased physical and chemical stability. Therefore, the agglomeration and oxidation which are the most problematic concerns in biomedical applications can be minimized or limited. Ultimately, these modifications make the nanoparticles biocompatible with enhanced surface activity. Following modifications, with the use of functional groups available on the surface of nanoparticles, targeted biomolecules can be anchored on nanoparticles [72]. Magnetic nanoparticles acquire higher surface energy due to its tremendous

Simply, modification of magnetic nanoparticles can be achieved by surface coating of the nanoparticle with either organic or inorganic materials. Inorganic materials include silica [74] and carbon [74]. Silica is a widely used compound for surface modification of iron oxide nanoparticles. As a result of its low cytotoxicity, silica modified nanoparticles are considered as an excellent combination to be used in biological applications. Silica coatings provide reduced agglomeration along with enhanced stability which ultimately ensures biocompatible-modified magnetic nanoparticles [75]. Organic material coating involves the addition of the material on to the nanoparticle, and the surface structure of the nanoparticle is totally undisturbed. There are many organic materials used for this strategy. Some of them are dextran [76], chitosan [77], alginate [78], and polymers such as polyethylene glycol (PEG) [79], polyvinyl alcohol (PVA) [80], and polyvinylpyr-

In drug delivery systems and diagnostics, nanotechnology has become a leader in the current decade. Since the 1980s there has been a considerable number of research on using nanotechnology in drug delivery systems [82, 83]. Due to its unique properties, such as smaller nanoscale size, magnetism, and fluorescence, nanotechnology-based drug delivery systems have defeated the problems and barriers of drug therapy in the pharmaceutical industry. Studies demonstrate many nanoparticulate drug careers, namely, liposomes [84], microemulsions [85], nano-suspensions [86], and nanoparticles [87]. These can be administrated through parenteral, tablets, capsules (as hard gelatin or soft gelatin), and as oral liquid [88].

*DOI: http://dx.doi.org/10.5772/intechopen.88611*

**bioconjugation**

[69] and in immuno-staining of cells [70], DNA [71], etc.

specific surface area of exposed atoms on its surface [73].

*Magnetic and Quantum Dot Nanoparticles for Drug Delivery and Diagnostic Systems DOI: http://dx.doi.org/10.5772/intechopen.88611*

quantum dots in biotechnology. As the fluorescence of quantum dots is intense than other conventional dyes classically used in immuno-labeling and staining of proteins, quantum dots are currently being used in immunoassays as fluorophores [69] and in immuno-staining of cells [70], DNA [71], etc.

#### **3. Advantages and advances in encapsulation of nanoparticles for bioconjugation**

Bare nanoparticles often show undesirable properties in biological systems. These nanoparticles are often hydrophobic or hydrophilic, susceptible to oxidation and agglomeration. The main concern with magnetic nanoparticles is that they may fail to exhibit their super-paramagnetic properties inside or when conjugated to biological systems. This reduction of magnetism occurs as a consequence of their high chemical reactivity and extraordinary surface energy [16]. With the intention of maintaining nanoparticles in the colloidal condition during storage and to increase their constancy and biocompatibility, bare nanoparticles are further modified. Generally, surface modification is performed using polymers or surfactants which are hefty or charged molecules compared to the nanoparticles. These modifications provide several advantages such as increased physical and chemical stability. Therefore, the agglomeration and oxidation which are the most problematic concerns in biomedical applications can be minimized or limited. Ultimately, these modifications make the nanoparticles biocompatible with enhanced surface activity. Following modifications, with the use of functional groups available on the surface of nanoparticles, targeted biomolecules can be anchored on nanoparticles [72]. Magnetic nanoparticles acquire higher surface energy due to its tremendous specific surface area of exposed atoms on its surface [73].

Simply, modification of magnetic nanoparticles can be achieved by surface coating of the nanoparticle with either organic or inorganic materials. Inorganic materials include silica [74] and carbon [74]. Silica is a widely used compound for surface modification of iron oxide nanoparticles. As a result of its low cytotoxicity, silica modified nanoparticles are considered as an excellent combination to be used in biological applications. Silica coatings provide reduced agglomeration along with enhanced stability which ultimately ensures biocompatible-modified magnetic nanoparticles [75]. Organic material coating involves the addition of the material on to the nanoparticle, and the surface structure of the nanoparticle is totally undisturbed. There are many organic materials used for this strategy. Some of them are dextran [76], chitosan [77], alginate [78], and polymers such as polyethylene glycol (PEG) [79], polyvinyl alcohol (PVA) [80], and polyvinylpyrrolidone (PVP) [81].

#### **4. Different methods of drug delivery**

In drug delivery systems and diagnostics, nanotechnology has become a leader in the current decade. Since the 1980s there has been a considerable number of research on using nanotechnology in drug delivery systems [82, 83]. Due to its unique properties, such as smaller nanoscale size, magnetism, and fluorescence, nanotechnology-based drug delivery systems have defeated the problems and barriers of drug therapy in the pharmaceutical industry. Studies demonstrate many nanoparticulate drug careers, namely, liposomes [84], microemulsions [85], nano-suspensions [86], and nanoparticles [87]. These can be administrated through parenteral, tablets, capsules (as hard gelatin or soft gelatin), and as oral liquid [88].

*Colloid Science in Pharmaceutical Nanotechnology*

core-type quantum dots [43].

*Types of quantum dots used in drug delivery [44].*

**Figure 1.**

ent internal structures [44].

*2.2.2 Synthesis of quantum dots*

Core-shell-type quantum dots, such as CdTe/CdSe [41], CdSe/ZnS [42], CdSe/ CdS, etc., are comprised of an inorganic core and an inorganic shell, generally a higher bandgap semiconductor around the core. Core-shell structures of quantum dots are more effective and have an intense brightness, as a result of the diminished chemical damage that can be happened to the fluorescence core. It is believed that inorganic core-shell quantum dots are more robust than organically passivated

Alloyed quantum dots are synthesized by alloying two semiconductors with different bandgap energies. This type emits colors by just altering the composition rather than changing the crystallite size as a result of both homogenous and gradi-

Among several methods utilized to synthesis quantum dots, hydrothermal synthesis [45, 46], and organometallic synthesis [47, 48] are the mainly used two techniques. Other methods, for instance, polyol-hydrolysis [49], electron beam irradiation [50], microwave-assisted aqueous synthesis [51], photochemical synthesis [52], UV irradiation [53], and chemical precipitation [54], are also less commonly used for quantum dot synthesis. CdTe quantum dots are highly used in biomedical applications compared to other types of quantum dots. Generally, CdTe quantum dots demonstrate inferior biocompatibility and stability in biological systems. Therefore, methods have developed to modify the surface of CdTe quantum dots during synthesis by capping the quantum dots using different stabilizers such as trioctylphosphine (TOP)/trioctylphosphine oxide (TOPO) [55], etc. Particularly, quantum dots which are capped with stabilizers containing thiol groups [56] make the quantum dots highly biocompatible and more stable inside biological environment [57, 58]. The CdTe quantum dots, which are synthesized in aqueous medium using thioglycolic acid [59], cysteine [60], and glutathione [61], provide high luminescence, stability, and surface functionalization to conjugate

Recently, quantum dots are used in many biotechnological appliances [6, 62]. These fluorescent nanocrystals are utilized in many immunofluorescence assays [63], tissue engineering [64], DNA array technology [65], and other cell biology techniques [66] where fluorescence measurements are occupied. Single-molecule level studies of living cells [67] and targeted drug delivery for cancer treatment [68] are some other applications in medicine. There are many advantages of using

**20**

biomolecules.

*2.2.3 Biomedical application*

These nanoparticles are extraordinary carriers for drug delivery for cancer treatment since they are not uptaken by phagocytosis by the immune system due to its nanoscale size [89].

Nanotechnology-based drug delivery has now come into a point where it has developed a smart drug delivery system. The theory behind smart drug delivery technique is, when the nanoparticle system is provoked by biological, chemical, or physical stimuli (biomolecules, pH, light, temperature, etc.), physicochemical properties of nanoparticle system change rapidly [90]. These smart drug delivery systems can be programmed to release drugs according to the stimuli, and the flow rate of drug release can be regulated according to the environmental condition. It can also predict the drugs required and switch on and off the release of drugs [91]. These advances have made the system more effective and have reduced the toxicity and side effects of the nanoparticulate drug admonition.

#### **4.1 Types of drug delivery**

There are several drug delivery methods such as oral method [92], injectionbased method [93], transdermal delivery [94], pulmonary drug delivery [95], and carrier-based method [96].

In oral drug delivery, formulations used in oral drug administration range from simple tablets to modified control release tablets. This involves the use of various polymers and hydrogel-based formulations [92]. Injection-based drug delivery provides fast systemic effects bypassing first pass metabolism. Using this method, the drugs can be administered in unconscious or comatose patients, and drugs having short half-life can also be infused continuously [93]. Pulmonary drug delivery involves the administration of drugs by inhalation through the mouth or nose. The alveolar epithelial gets contacted with the drugs, and this provides a good surface especially for lipid-soluble drugs [95]. In transdermal drug administration, adhesive patches containing the drugs are applied on the skin. The drugs pass the skin surface by diffusion and enter the systemic circulation by percutaneous absorption [94]. Carrier-based drug delivery is a novel method which has been experimenting over decades in order to escalate the efficiency and diminish the detrimental side effects of carrier systems. This method serves improved selectivity, effectiveness, and safety of drug administration [96].

#### *4.1.1 Carrier-based drug delivery systems*

Carrier-based drug delivery system utilizes several carriers such as liposomes, microemulsions, micellar systems, aquasomes, and nanoparticles.

Liposomes are drug carriers with a spherical structure, constructed from one or several amphiphilic phospholipids and cholesterols. Using liposomes as vehicles in drug delivery provides various conveniences compared to other systems. These carriers are created as small structures (80–100 nm), with bilayers of phospholipids and cholesterols with an aqueous interior. As a result, lipophilic drugs can be encapsulated in the lipid bilayer and hydrophilic drugs in the aqueous interior [85]. Using liposomes are considered as a low-toxic method with minimal side effects, and the drug can be applied without deteriorating its performance [84].

Microemulsions are a thermodynamically stable mixture of two immiscible liquids consisting of two phases called dispersed and continuous phase. These mixtures are typically stabilized with a surfactant and may have droplets with a size of 5–100 nm length [85]. Similar to emulsions, microemulsions can also be constructed as water in oil or oil in water. In drug administration, dispersed or continuous

**23**

**Figure 2.**

*Preparation of aquasomes [98].*

*Magnetic and Quantum Dot Nanoparticles for Drug Delivery and Diagnostic Systems*

phases are determined by the hydrophilicity of the drug. Microemulsions provide increased solubility and stability of drugs enhancing high absorption rate through

Composed of copolymers and amphiphilic macromolecules with distinct hydrophobic and hydrophilic properties, polymer micelles form nanoscopic supramolecular core-shell structures. These structures show different types of morphologies, such as spheres, rods, vesicles, tubules, and lamellae. Core-shell structure of these particles grants a number of positive factors to be used in drug delivery applications [85]. As a result of the copolymers used in the formation of the micelles, the half-life of the system is expanded. Another consideration is that water-insoluble drugs can be solubilized by encapsulating the drug within the core structure. Due to its nanoscopic size, the permeability is intensified making it

Aquasomes are spherical particles with 60–300 nm in size. These are used as vehicles for drug delivery as well as to deliver antigens to evoke antigen-specific immune responses [85]. These nanoparticles are comprised of a nanocrystalline core, which is responsible for the structural stability, and an oligomer coating, which protects the system from dehydration. As shown in **Figure 2**, the drugs or biomolecules of interest are adsorbed on the oligomeric coating of the aquasomes,

Nanoparticles are solid colloidal particles with 1–1000 nm size [18]. Currently, a number of different types of nanoparticles along with various macromolecules are used for drug delivery. Nanoparticles in different structures are produced depending on their configuration and utility such as nanotubes [99], nanowires [100], nanoshells [101], quantum dots [102], nanopores, nanobots [103], nanoerythrocytes [104], etc. Drugs or biomolecules are attached to the nanoparticles by adsorption, covalent attachment, or entrapment [18]. To be included in the drug development process, utilization of potentially toxic compounds or organic solvents in the nanoparticle synthesis procedure is inadvisable [44]. The components used in synthesis should ideally be biodegradable and safe for in vivo use. Further, these complexes should not induce immunological responses, and also, these should be stable under storage conditions [105]. In drug delivery, magnetic nanoparticles are being used in several approaches. The first approach is localized drug delivery, where the magnetic nanoparticles attached to the appropriate drug and administered systemically. When the magnetic field is applied on the required site of the body, these drug-containing magnetic nanoparticles will accumulate on the diseased site, and the drugs will be released for treatment [106]. The second approach is the usage of an alternate magnetic field to generate heat by magnetic nanoparticles which are conjugated to drugs via thermos-liable linker molecules [107]. These magnetic nanoparticles have the ability to generate heat when an alternate magnetic field is focused on a diseased site. Thus, under the alternate magnetic field, these

*DOI: http://dx.doi.org/10.5772/intechopen.88611*

biological membranes.

convenient for injections [97].

making them conducive for drug delivery [98].

thermos-liable linkers get cleaved, releasing the drugs [108].

#### *Magnetic and Quantum Dot Nanoparticles for Drug Delivery and Diagnostic Systems DOI: http://dx.doi.org/10.5772/intechopen.88611*

phases are determined by the hydrophilicity of the drug. Microemulsions provide increased solubility and stability of drugs enhancing high absorption rate through biological membranes.

Composed of copolymers and amphiphilic macromolecules with distinct hydrophobic and hydrophilic properties, polymer micelles form nanoscopic supramolecular core-shell structures. These structures show different types of morphologies, such as spheres, rods, vesicles, tubules, and lamellae. Core-shell structure of these particles grants a number of positive factors to be used in drug delivery applications [85]. As a result of the copolymers used in the formation of the micelles, the half-life of the system is expanded. Another consideration is that water-insoluble drugs can be solubilized by encapsulating the drug within the core structure. Due to its nanoscopic size, the permeability is intensified making it convenient for injections [97].

Aquasomes are spherical particles with 60–300 nm in size. These are used as vehicles for drug delivery as well as to deliver antigens to evoke antigen-specific immune responses [85]. These nanoparticles are comprised of a nanocrystalline core, which is responsible for the structural stability, and an oligomer coating, which protects the system from dehydration. As shown in **Figure 2**, the drugs or biomolecules of interest are adsorbed on the oligomeric coating of the aquasomes, making them conducive for drug delivery [98].

Nanoparticles are solid colloidal particles with 1–1000 nm size [18]. Currently, a number of different types of nanoparticles along with various macromolecules are used for drug delivery. Nanoparticles in different structures are produced depending on their configuration and utility such as nanotubes [99], nanowires [100], nanoshells [101], quantum dots [102], nanopores, nanobots [103], nanoerythrocytes [104], etc. Drugs or biomolecules are attached to the nanoparticles by adsorption, covalent attachment, or entrapment [18]. To be included in the drug development process, utilization of potentially toxic compounds or organic solvents in the nanoparticle synthesis procedure is inadvisable [44]. The components used in synthesis should ideally be biodegradable and safe for in vivo use. Further, these complexes should not induce immunological responses, and also, these should be stable under storage conditions [105]. In drug delivery, magnetic nanoparticles are being used in several approaches. The first approach is localized drug delivery, where the magnetic nanoparticles attached to the appropriate drug and administered systemically. When the magnetic field is applied on the required site of the body, these drug-containing magnetic nanoparticles will accumulate on the diseased site, and the drugs will be released for treatment [106]. The second approach is the usage of an alternate magnetic field to generate heat by magnetic nanoparticles which are conjugated to drugs via thermos-liable linker molecules [107]. These magnetic nanoparticles have the ability to generate heat when an alternate magnetic field is focused on a diseased site. Thus, under the alternate magnetic field, these thermos-liable linkers get cleaved, releasing the drugs [108].

**Figure 2.** *Preparation of aquasomes [98].*

*Colloid Science in Pharmaceutical Nanotechnology*

and side effects of the nanoparticulate drug admonition.

nanoscale size [89].

**4.1 Types of drug delivery**

carrier-based method [96].

and safety of drug administration [96].

*4.1.1 Carrier-based drug delivery systems*

These nanoparticles are extraordinary carriers for drug delivery for cancer treatment since they are not uptaken by phagocytosis by the immune system due to its

Nanotechnology-based drug delivery has now come into a point where it has developed a smart drug delivery system. The theory behind smart drug delivery technique is, when the nanoparticle system is provoked by biological, chemical, or physical stimuli (biomolecules, pH, light, temperature, etc.), physicochemical properties of nanoparticle system change rapidly [90]. These smart drug delivery systems can be programmed to release drugs according to the stimuli, and the flow rate of drug release can be regulated according to the environmental condition. It can also predict the drugs required and switch on and off the release of drugs [91]. These advances have made the system more effective and have reduced the toxicity

There are several drug delivery methods such as oral method [92], injectionbased method [93], transdermal delivery [94], pulmonary drug delivery [95], and

In oral drug delivery, formulations used in oral drug administration range from simple tablets to modified control release tablets. This involves the use of various polymers and hydrogel-based formulations [92]. Injection-based drug delivery provides fast systemic effects bypassing first pass metabolism. Using this method, the drugs can be administered in unconscious or comatose patients, and drugs having short half-life can also be infused continuously [93]. Pulmonary drug delivery involves the administration of drugs by inhalation through the mouth or nose. The alveolar epithelial gets contacted with the drugs, and this provides a good surface especially for lipid-soluble drugs [95]. In transdermal drug administration, adhesive patches containing the drugs are applied on the skin. The drugs pass the skin surface by diffusion and enter the systemic circulation by percutaneous absorption [94]. Carrier-based drug delivery is a novel method which has been experimenting over decades in order to escalate the efficiency and diminish the detrimental side effects of carrier systems. This method serves improved selectivity, effectiveness,

Carrier-based drug delivery system utilizes several carriers such as liposomes,

Liposomes are drug carriers with a spherical structure, constructed from one or several amphiphilic phospholipids and cholesterols. Using liposomes as vehicles in drug delivery provides various conveniences compared to other systems. These carriers are created as small structures (80–100 nm), with bilayers of phospholipids and cholesterols with an aqueous interior. As a result, lipophilic drugs can be encapsulated in the lipid bilayer and hydrophilic drugs in the aqueous interior [85]. Using liposomes are considered as a low-toxic method with minimal side effects, and the

Microemulsions are a thermodynamically stable mixture of two immiscible liquids consisting of two phases called dispersed and continuous phase. These mixtures are typically stabilized with a surfactant and may have droplets with a size of 5–100 nm length [85]. Similar to emulsions, microemulsions can also be constructed as water in oil or oil in water. In drug administration, dispersed or continuous

microemulsions, micellar systems, aquasomes, and nanoparticles.

drug can be applied without deteriorating its performance [84].

**22**

### **5. Conclusion**

Recent advances of nanotechnology which is used in biomedical science have given a great opportunity for the consumers to utilize the technology in a very efficient manner. Special focus on smart drug delivery technique which provides utmost advantages can prove this statement without hesitation. Nanoparticles, being considered as highly useful components in drug delivery, therapeutics, and diagnostics, can also affect its users negatively as a result of its inherent toxicity and inferior levels of biocompatibility. Even though different types of nanoparticles show diverse levels of toxicities, current appliances have made precautions to minimize its toxic effect and increase biocompatibility, by encapsulation. Magnetic nanoparticles and quantum dot nanoparticles, as discussed in this chapter, are used widely in the aforementioned applications with modified surface fabrications. The future prospects of nanotechnology in biomedical applications could lead to a highly sophisticated user-friendly technology where smarter appliances will reach consumers with the least challenges which they encounter in the present systems.

### **Acknowledgements**

Financial assistance given by the National Research Council, Sri Lanka (NRC-TO 14-04).

### **Author details**

Erandi Munasinghe1 \*, Maheshi Aththapaththu2 and Lakmal Jayarathne3

1 Molecular Medicine Unit, Faculty of Medicine, University of Kelaniya, Sri Lanka

2 Biotechnology Unit, Industrial Technology Institute, Colombo, Sri Lanka

3 National Institute of Fundamental Studies, Kandy, Sri Lanka

\*Address all correspondence to: erandieran@hotmail.com

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

**25**

*Magnetic and Quantum Dot Nanoparticles for Drug Delivery and Diagnostic Systems*

triggered photo-therapy, in

Carbon. 2017;**118**:752-764

[10] Terris B, Thomson T.

Physics. 2005;**38**(12):R199

[11] Kefeni KK, Msagati TA, Mamba BB. Ferrite nanoparticles: Synthesis, characterisation and applications in electronic device. Materials Science and Engineering B.

[12] Reddy LH, Arias JL, Nicolas J, Couvreur P. Magnetic nanoparticles: Design and characterization, toxicity and biocompatibility, pharmaceutical and biomedical applications. Chemical Reviews. 2012;**112**(11):5818-5878

[13] Nosrati H, Salehiabar M, Manjili HK, Danafar H, Davaran S. Preparation of magnetic albumin nanoparticles via a simple and onepot desolvation and co-precipitation method for medical and pharmaceutical applications. International Journal of Biological Macromolecules.

[14] Ahmad M, Minhas MU, Sohail M, Faisal M, Rashid H. Comprehensive review on magnetic drug delivery systems: A novel approach for drug targeting. Journal of Pharmacy and Alternative Medicine. 2013;**2**(4):13-21

[15] Katikaneani P, Vaddepally AK, Reddy Tippana N, Banavath R, Kommu S. Phase

2018;**108**:909-915

2010;**2**(6):917-919

2017;**215**:37-55

[9] Zhang D, Wei S, Kaila C,

Su X, Wu J, Karki AB, et al. Carbonstabilized iron nanoparticles for

Nanofabricated and self-assembled magnetic structures as data storage media. Journal of Physics D: Applied

environmental remediation. Nanoscale.

combination with chemotherapy using magnetofluorescent carbon quantum dots for effective cancer treating.

*DOI: http://dx.doi.org/10.5772/intechopen.88611*

[1] Singh P, Pandit S, Mokkapati V, Garg A, Ravikumar V, Mijakovic I. Gold

nanoparticles in diagnostics and therapeutics for human cancer. International Journal of Molecular

Sciences. 2018;**19**(7):1979

[2] Dadfar SM, Roemhild K,

Kiessling F, et al. Iron oxide

and theranostic applications. Advanced Drug Delivery Reviews.

[3] Manoharan K, Saha A,

2019;**138**:302-325

2019;**37**(2):454-464

2012;**33**(14):3710-3718

2015;**9**(8):8449-8457

2016;**17**(22):2103-2114

Drude NI, von Stillfried S, Knüchel R,

nanoparticles: Diagnostic, therapeutic

Bhattacharya S. Nanoparticles-based diagnostics. In: Environmental, Chemical and Medical Sensors. Singapore: Springer; 2018. pp. 253-269

[4] Khorram R, Raissi H, Morsali A, Shahabi M, et al. The computational study of the γ-Fe2O3 nanoparticle as carmustine drug delivery[PP3] system: DFT approach. Journal of Biomolecular Structure and Dynamics.

[5] Gao W, Ji L, Li L, Cui G, Xu K, Li P, et al. Bifunctional combined Au-Fe2O3

[6] Qiu X, Hildebrandt N. Rapid and multiplexed microRNA diagnostic assay using quantum dot-based Forster resonance energy transfer. ACS Nano.

[7] Bilan R, Nabiev I, Sukhanova A. Quantum dot-based Nanotools for bioimaging, diagnostics, and drug delivery. Chembiochem.

[8] Zhang M, Wang W, Zhou N, Yuan P, Su Y, Shao M, et al. Near-infrared light

nanoparticles for induction of cancer cell-specific apoptosis and real-time imaging. Biomaterials.

**References**

*Magnetic and Quantum Dot Nanoparticles for Drug Delivery and Diagnostic Systems DOI: http://dx.doi.org/10.5772/intechopen.88611*

#### **References**

*Colloid Science in Pharmaceutical Nanotechnology*

Recent advances of nanotechnology which is used in biomedical science have given a great opportunity for the consumers to utilize the technology in a very efficient manner. Special focus on smart drug delivery technique which provides utmost advantages can prove this statement without hesitation. Nanoparticles, being considered as highly useful components in drug delivery, therapeutics, and diagnostics, can also affect its users negatively as a result of its inherent toxicity and inferior levels of biocompatibility. Even though different types of nanoparticles show diverse levels of toxicities, current appliances have made precautions to minimize its toxic effect and increase biocompatibility, by encapsulation. Magnetic nanoparticles and quantum dot nanoparticles, as discussed in this chapter, are used widely in the aforementioned applications with modified surface fabrications. The future prospects of nanotechnology in biomedical applications could lead to a highly sophisticated user-friendly technology where smarter appliances will reach consumers with the least challenges which they encounter in the present systems.

Financial assistance given by the National Research Council, Sri Lanka (NRC-TO

and Lakmal Jayarathne3

\*, Maheshi Aththapaththu2

3 National Institute of Fundamental Studies, Kandy, Sri Lanka

\*Address all correspondence to: erandieran@hotmail.com

provided the original work is properly cited.

1 Molecular Medicine Unit, Faculty of Medicine, University of Kelaniya, Sri Lanka

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

2 Biotechnology Unit, Industrial Technology Institute, Colombo, Sri Lanka

**5. Conclusion**

**Acknowledgements**

14-04).

**Author details**

Erandi Munasinghe1

**24**

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[51] Zhang J, Chen Q, Zhang W, Mei S, He L, Zhu J, et al. Microwave-assisted aqueous synthesis of transition metal ions doped ZnSe/ZnS core/shell quantum dots with tunable white-light emission. Applied Surface Science. 2015;**351**:655-661

[52] Fageria P, Uppala S, Nazir R, Gangopadhyay S, Chang C-H, Basu M, et al. Synthesis of monometallic (Au and Pd) and bimetallic (AuPd) nanoparticles using carbon nitride (C3N4) quantum dots via the photochemical route for

nitrophenol reduction. Langmuir. 2016;**32**(39):10054-10064

[53] Lu X, Wang R, Hao L, Yang F, Jiao W, Zhang J, et al. Preparation of quantum dots from MoO 3 nanosheets by UV irradiation and insight into morphology changes. Journal of Materials Chemistry C. 2016;**4**(48):11449-11456

[54] Rajabi HR, Farsi M. Study of capping agent effect on the structural, optical and photocatalytic properties of zinc sulfide quantum dots. Materials Science in Semiconductor Processing. 2016;**48**:14-22

[55] Paim APS, Rodrigues SSM, Ribeiro DS, de Souza GC, Santos JL, Araújo AN, et al. Fluorescence probe for mercury (ii) based on the aqueous synthesis of CdTe quantum dots stabilized with 2-mercaptoethanesulfonate. New Journal of Chemistry. 2017;**41**(9):3265-3272

[56] Wuister SF, de Mello Donega C, Meijerink A. Influence of thiol capping on the exciton luminescence and decay kinetics of CdTe and CdSe quantum dots. The Journal of Physical Chemistry B. 2004;**108**(45):17393-17397

[57] Wuister SF, Swart I, van Driel F, Hickey SG, de Mello Donegá C. Highly luminescent water-soluble CdTe quantum dots. Nano Letters. 2003;**3**(4):503-507

[58] Ma J, Chen J-Y, Guo J, Wang C, Yang W, Xu L, et al. Photostability of thiol-capped CdTe quantum dots in living cells: The effect of photo-oxidation. Nanotechnology. 2006;**17**(9):2083

[59] Jhonsi MA, Renganathan R. Investigations on the photoinduced interaction of water soluble thioglycolic acid (TGA) capped CdTe quantum dots with certain porphyrins. Journal

**29**

*Magnetic and Quantum Dot Nanoparticles for Drug Delivery and Diagnostic Systems*

quantum dot applications. Theranostics.

[68] Iannazzo D, Pistone A, Salamò M, Galvagno S, Romeo R, Giofré SV, et al. Graphene quantum dots for cancer targeted drug delivery. International

[69] Chen L, Yang G, Wu P, Cai C. Realtime fluorescence assay of alkaline phosphatase in living cells using boron-doped graphene quantum dots as fluorophores. Biosensors and Bioelectronics. 2017;**96**:294-299

[70] Tu C-C, Chen K-P, Yang T-A, Chou M-Y, Lin LY, Li Y-K. Silicon quantum dot nanoparticles with antifouling coatings for immunostaining on live cancer cells. ACS Applied Materials & Interfaces.

quantum dots as biological sensors. ACS Chemical Biology. 2017;**13**(7):1705-1713

Pourfatollah AA, Pazoki-Toroudi H, Sedighimoghaddam B. Various

[73] Wu W, He Q, Jiang C. Magnetic iron oxide nanoparticles: Synthesis and surface functionalization

strategies. Nanoscale Research Letters.

[74] Yi DK, Selvan ST, Lee SS, Papaefthymiou GC, Kundaliya D, Ying JY. Silica-coated nanocomposites of magnetic nanoparticles and quantum dots. Journal of the American Chemical Society. 2005;**127**(14):4990-4991

[75] Malvindi MA, De

Matteis V, Galeone A, Brunetti V, Anyfantis GC, Athanassiou A, et al. Toxicity assessment of silica coated

2008;**3**(11):397

methods of gold nanoparticles (GNPs) conjugation to antibodies. Sensing and Bio-Sensing Research. 2016;**9**:17-22

Journal of Pharmaceutics. 2017;**518**(1-2):185-192

2016;**8**(22):13714-13723

[71] Wang G, Li Z, Ma N. Nextgeneration DNA-functionalized

[72] Jazayeri MH, Amani H,

2012;**2**(7):655

*DOI: http://dx.doi.org/10.5772/intechopen.88611*

Choi HJ, Joo WH, Shin SK, et al. Highly

[61] Zheng Y, Gao S, Ying JY. Synthesis

quantum dots. Advanced Materials.

[62] Guo R, Zhou S, Li Y, Li X, Fan L, Voelcker NH. Rhodamine-functionalized graphene quantum dots for detection of Fe3+ in cancer stem cells. ACS Applied Materials & Interfaces.

[63] Wu S, Liu L, Li G, Jing F, Mao H, Jin Q, et al. Multiplexed detection of lung cancer biomarkers based on quantum dots and microbeads. Talanta.

[64] Zhao H, Ding R, Zhao X, Li Y, Qu L, Pei H, et al. Graphene-based nanomaterials for drug and/or gene delivery, bioimaging, and tissue engineering. Drug Discovery Today.

[65] Fan L, Qi H, Teng J, Su B, Chen H, Wang C, et al. Identification of serum miRNAs by nano-quantum dots microarray as diagnostic biomarkers for early detection of non-small cell lung cancer. Tumor Biology.

[66] Han H-S, Niemeyer E, Huang Y, Kamoun WS, Martin JD, Bhaumik J, et al. Quantum dot/antibody conjugates for in vivo cytometric imaging in mice. Proceedings of the National Academy of

Sciences. 2015;**112**(5):1350-1355

[67] Baba K, Nishida K. Single-molecule tracking in living cells using single

of Colloid and Interface Science.

[60] Kim J, Huy BT, Sakthivel K,

fluorescent CdTe quantum dots with reduced cytotoxicity-a robust biomarker. Sensing and Bio-Sensing

and cell-imaging applications of glutathione-capped CdTe

2010;**344**(2):596-602

Research. 2015;**3**:46-52

2007;**19**(3):376-380

2015;**7**(43):23958-23966

2016;**156**:48-54

2017;**22**(9):1302-1317

2016;**37**(6):7777-7784

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of Colloid and Interface Science. 2010;**344**(2):596-602

*Colloid Science in Pharmaceutical Nanotechnology*

water-soluble MoS2 quantum dots via a hydrothermal method as a fluorescent probe for hyaluronidase detection. ACS Applied Materials & Interfaces.

nitrophenol reduction. Langmuir.

[53] Lu X, Wang R, Hao L, Yang F, Jiao W, Zhang J, et al. Preparation of

[54] Rajabi HR, Farsi M. Study of capping agent effect on the structural, optical and photocatalytic properties of zinc sulfide quantum dots. Materials Science in Semiconductor Processing.

[55] Paim APS, Rodrigues SSM, Ribeiro DS, de Souza GC, Santos JL, Araújo AN, et al. Fluorescence probe

for mercury (ii) based on the aqueous synthesis of CdTe quantum dots stabilized with 2-mercaptoethanesulfonate. New Journal of Chemistry. 2017;**41**(9):3265-3272

[56] Wuister SF, de Mello Donega C, Meijerink A. Influence of thiol capping on the exciton luminescence and decay kinetics of CdTe and CdSe quantum dots. The Journal of Physical Chemistry B. 2004;**108**(45):17393-17397

[57] Wuister SF, Swart I, van Driel F, Hickey SG, de Mello Donegá C. Highly luminescent water-soluble CdTe quantum dots. Nano Letters.

[58] Ma J, Chen J-Y, Guo J, Wang C, Yang W, Xu L, et al. Photostability of thiol-capped CdTe quantum dots in living cells: The effect of photo-oxidation. Nanotechnology.

[59] Jhonsi MA, Renganathan R. Investigations on the photoinduced interaction of water soluble thioglycolic acid (TGA) capped CdTe quantum dots with certain porphyrins. Journal

2003;**3**(4):503-507

2006;**17**(9):2083

2016;**32**(39):10054-10064

quantum dots from MoO 3 nanosheets by UV irradiation and insight into morphology changes. Journal of Materials Chemistry C.

2016;**4**(48):11449-11456

2016;**48**:14-22

[46] Ren X, Pang L, Zhang Y, Ren X, Fan H, Liu SF. One-step hydrothermal

[47] Chen N, He Y, Su Y, Li X, Huang Q, Wang H, et al. The cytotoxicity of cadmium-based quantum dots. Biomaterials. 2012;**33**(5):1238-1244

[48] Bao H, Lu Z, Cui X, Qiao Y,

2010;**6**(9):3534-3541

2011;**3**(11):1772-1778

Journal. 2017;**309**:374-380

2015;**351**:655-661

Guo J, Anderson JM, et al. Extracellular microbial synthesis of biocompatible CdTe quantum dots. Acta Biomaterialia.

[49] Xin Y, Yang X, Jiang P, Zhang Z, Wang Z, Zhang Y. Synthesis of CeO2 based quantum dots through a Polyol-hydrolysis method for fuelborne catalysts. ChemCatChem.

[50] Wang L, Li W, Wu B, Li Z, Pan D, Wu M. Room-temperature synthesis of graphene quantum dots via electronbeam irradiation and their application in cell imaging. Chemical Engineering

[51] Zhang J, Chen Q, Zhang W, Mei S, He L, Zhu J, et al. Microwave-assisted aqueous synthesis of transition metal ions doped ZnSe/ZnS core/shell quantum dots with tunable white-light emission. Applied Surface Science.

[52] Fageria P, Uppala S, Nazir R, Gangopadhyay S, Chang C-H, Basu M, et al. Synthesis of monometallic (Au and Pd) and bimetallic (AuPd) nanoparticles using carbon nitride (C3N4) quantum dots via the photochemical route for

synthesis of monolayer MoS2 quantum dots for highly efficient electrocatalytic hydrogen evolution. Journal of Materials Chemistry A.

2016;**8**(18):11272-11279

2015;**3**(20):10693-10697

**28**

[60] Kim J, Huy BT, Sakthivel K, Choi HJ, Joo WH, Shin SK, et al. Highly fluorescent CdTe quantum dots with reduced cytotoxicity-a robust biomarker. Sensing and Bio-Sensing Research. 2015;**3**:46-52

[61] Zheng Y, Gao S, Ying JY. Synthesis and cell-imaging applications of glutathione-capped CdTe quantum dots. Advanced Materials. 2007;**19**(3):376-380

[62] Guo R, Zhou S, Li Y, Li X, Fan L, Voelcker NH. Rhodamine-functionalized graphene quantum dots for detection of Fe3+ in cancer stem cells. ACS Applied Materials & Interfaces. 2015;**7**(43):23958-23966

[63] Wu S, Liu L, Li G, Jing F, Mao H, Jin Q, et al. Multiplexed detection of lung cancer biomarkers based on quantum dots and microbeads. Talanta. 2016;**156**:48-54

[64] Zhao H, Ding R, Zhao X, Li Y, Qu L, Pei H, et al. Graphene-based nanomaterials for drug and/or gene delivery, bioimaging, and tissue engineering. Drug Discovery Today. 2017;**22**(9):1302-1317

[65] Fan L, Qi H, Teng J, Su B, Chen H, Wang C, et al. Identification of serum miRNAs by nano-quantum dots microarray as diagnostic biomarkers for early detection of non-small cell lung cancer. Tumor Biology. 2016;**37**(6):7777-7784

[66] Han H-S, Niemeyer E, Huang Y, Kamoun WS, Martin JD, Bhaumik J, et al. Quantum dot/antibody conjugates for in vivo cytometric imaging in mice. Proceedings of the National Academy of Sciences. 2015;**112**(5):1350-1355

[67] Baba K, Nishida K. Single-molecule tracking in living cells using single

quantum dot applications. Theranostics. 2012;**2**(7):655

[68] Iannazzo D, Pistone A, Salamò M, Galvagno S, Romeo R, Giofré SV, et al. Graphene quantum dots for cancer targeted drug delivery. International Journal of Pharmaceutics. 2017;**518**(1-2):185-192

[69] Chen L, Yang G, Wu P, Cai C. Realtime fluorescence assay of alkaline phosphatase in living cells using boron-doped graphene quantum dots as fluorophores. Biosensors and Bioelectronics. 2017;**96**:294-299

[70] Tu C-C, Chen K-P, Yang T-A, Chou M-Y, Lin LY, Li Y-K. Silicon quantum dot nanoparticles with antifouling coatings for immunostaining on live cancer cells. ACS Applied Materials & Interfaces. 2016;**8**(22):13714-13723

[71] Wang G, Li Z, Ma N. Nextgeneration DNA-functionalized quantum dots as biological sensors. ACS Chemical Biology. 2017;**13**(7):1705-1713

[72] Jazayeri MH, Amani H, Pourfatollah AA, Pazoki-Toroudi H, Sedighimoghaddam B. Various methods of gold nanoparticles (GNPs) conjugation to antibodies. Sensing and Bio-Sensing Research. 2016;**9**:17-22

[73] Wu W, He Q, Jiang C. Magnetic iron oxide nanoparticles: Synthesis and surface functionalization strategies. Nanoscale Research Letters. 2008;**3**(11):397

[74] Yi DK, Selvan ST, Lee SS, Papaefthymiou GC, Kundaliya D, Ying JY. Silica-coated nanocomposites of magnetic nanoparticles and quantum dots. Journal of the American Chemical Society. 2005;**127**(14):4990-4991

[75] Malvindi MA, De Matteis V, Galeone A, Brunetti V, Anyfantis GC, Athanassiou A, et al. Toxicity assessment of silica coated

iron oxide nanoparticles and biocompatibility improvement by surface engineering. PLoS One. 2014;**9**(1):e85835

[76] Nath S, Kaittanis C, Ramachandran V, Dalal NS, Perez JM. Synthesis, magnetic characterization, and sensing applications of novel dextran-coated iron oxide nanorods. Chemistry of Materials. 2009;**21**(8):1761-1767

[77] Agnihotri SA, Mallikarjuna NN, Aminabhavi TM. Recent advances on chitosan-based micro-and nanoparticles in drug delivery. Journal of Controlled Release. 2004;**100**(1):5-28

[78] Castelló J, Gallardo M, Busquets MA, Estelrich J. Chitosan (or alginate)-coated iron oxide nanoparticles: A comparative study. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 2015;**468**:151-158

[79] Inchaurraga L, Martín-Arbella N, Zabaleta V, Quincoces G, Peñuelas I, Irache JM. In vivo study of the mucuspermeating properties of PEGcoated nanoparticles following oral administration. European Journal of Pharmaceutics and Biopharmaceutics. 2015;**97**:280-289

[80] Strehl C, Schellmann S, Maurizi L, Hofmann-Amtenbrink M, Häupl T, Hofmann H, et al. Effects of PVA-coated nanoparticles on human T helper cell activity. Toxicology Letters. 2016;**245**:52-58

[81] Jaberolansar E, Kameli P, Ahmadvand H, Salamati H. Synthesis and characterization of PVPcoated Co0. 3Zn0. 7Fe2O4 ferrite nanoparticles. Journal of Magnetism and Magnetic Materials. 2016;**404**:21-28

[82] Labhasetwar V, Dorle A. Nanoparticles—A colloidal drug delivery system for primaquine and metronidazole. Journal of Controlled Release. 1990;**12**(2):113-119

[83] Li VH, Wood RW, Kreuter J, Harmia T, Robinson JR. Ocular drug delivery of progesterone using nanoparticles. Journal of Microencapsulation. 1986;**3**(3):213-218

[84] Malam Y, Loizidou M, Seifalian AM. Liposomes and nanoparticles: Nanosized vehicles for drug delivery in cancer. Trends in Pharmacological Sciences. 2009;**30**(11):592-599

[85] Majuru S, Oyewumi MO. Nanotechnology in drug development and life cycle management. In: Nanotechnology in Drug Delivery. New York: Springer; 2009. pp. 597-619

[86] Yadollahi R, Vasilev K, Simovic S. Nanosuspension technologies for delivery of poorly soluble drugs. Journal of Nanomaterials. 2015;**2015**:1

[87] Sahoo SK, Misra R, Parveen S. Nanoparticles: A boon to drug delivery, therapeutics, diagnostics and imaging. In: Nanomedicine in Cancer. Singapore: Pan Stanford; 2017. pp. 73-124

[88] De Villiers MM, Aramwit P, Kwon GS. Nanotechnology in Drug Delivery. New York: Springer Science & Business Media; 2008

[89] Zahr AS, de Villiers M, Pishko MV. Encapsulation of drug nanoparticles in self-assembled macromolecular nanoshells. Langmuir. 2005;**21**(1):403-410

[90] Liu D, Yang F, Xiong F, Gu N. The smart drug delivery system and its clinical potential. Theranostics. 2016;**6**(9):1306

[91] Cui W, Li J, Decher G. Selfassembled smart Nanocarriers for targeted drug delivery. Advanced Materials. 2016;**28**(6):1302-1311

[92] Amidon S, Brown JE, Dave VS. Colon-targeted oral drug delivery systems: Design trends and approaches. AAPS PharmSciTech. 2015;**16**(4):731-741

**31**

*Magnetic and Quantum Dot Nanoparticles for Drug Delivery and Diagnostic Systems*

nanoshells on drug-loaded micelles for colorectal cancer treatment. In: Colloidal Nanoparticles for Biomedical Applications XIII. California, United States: International Society for Optics

[102] Iannazzo D, Pistone A, Celesti C, Triolo C, Patané S, Giofré SV, et al. A smart Nanovector for cancer targeted drug delivery based on Graphene quantum dots. Nanomaterials.

Perez-Jiménez A, Blanco À, Sánchez S.

and Photonics; 2018

2019;**9**(2):282

[103] Hortelão AC, Patiño T,

Enzyme-powered Nanobots enhance anticancer drug delivery. Advanced Functional Materials.

[104] Hu CMJ, Fang RH, Zhang L. Erythrocyte-inspired delivery systems. Advanced Healthcare Materials.

[105] Tiwari G, Tiwari R, Sriwastawa B, Bhati L, Pandey S, Pandey P, et al. Drug delivery systems: An updated review. International Journal of Pharmaceutical

Johnson DT, Brazel CS. Heat generation of aqueously dispersed CoFe2O4 nanoparticles as heating agents for magnetically activated drug delivery and hyperthermia. Journal of Magnetism and Magnetic Materials.

2018;**28**(25):1705086

2012;**1**(5):537-547

Investigation. 2012;**2**(1):2

[106] Singh R, Lillard JW Jr. Nanoparticle-based targeted drug delivery. Experimental and Molecular Pathology. 2009;**86**(3):215-223

[107] Kim D-H, Nikles DE,

2008;**320**(19):2390-2396

[108] Kim S, Kwon K, Kwon IC, Park K. Nanotechnology in drug delivery: Past, present, and future. In: Nanotechnology in Drug Delivery. New York: Springer; 2009. pp. 581-596

*DOI: http://dx.doi.org/10.5772/intechopen.88611*

[93] Norouzi M, Nazari B, Miller DW. Injectable hydrogel-based drug delivery systems for local cancer therapy. Drug Discovery Today. 2016;**21**(11):1835-1849

[94] Marwah H, Garg T, Goyal AK, Rath G. Permeation enhancer strategies in transdermal drug delivery. Drug Delivery. 2016;**23**(2):564-578

[95] Pham D-D, Fattal E, Tsapis N. Pulmonary drug delivery systems for tuberculosis treatment. International

[96] Chen D, Lian S, Sun J, Liu Z, Zhao F, Jiang Y, et al. Design of novel multifunctional targeting nano-carrier drug delivery system based on CD44 receptor and tumor microenvironment

pH condition. Drug Delivery.

[97] Poelma SO, Oh SS, Helmy S, Knight AS, Burnett GL, Soh HT, et al. Controlled drug release to cancer cells from modular one-photon visible light-responsive micellar system. Chemical Communications.

[98] Umashankar MS, Sachdeva RK, Gulati M. Aquasomes: A promising carrier for peptides and protein delivery.

Nanomedicine: Nanotechnology,

[99] Bianco A, Kostarelos K, Prato M. Applications of carbon nanotubes in drug delivery. Current Opinion in Chemical Biology. 2005;**9**(6):674-679

Kishore U, Abelmann L, et al. Magnetic drug delivery with FePd nanowires. Journal of Magnetism and Magnetic

[100] Pondman KM, Bunt ND, Maijenburg AW, van Wezel RJ,

Materials. 2015;**380**:299-306

[101] Lee S-Y, Shieh M-J. Combined photothermo-chemotherapy using gold

2016;**23**(3):798-803

2016;**52**(69):10525-10528

Biology and Medicine. 2010;**6**(3):419-426

Journal of Pharmaceutics. 2015;**478**(2):517-529

*Magnetic and Quantum Dot Nanoparticles for Drug Delivery and Diagnostic Systems DOI: http://dx.doi.org/10.5772/intechopen.88611*

[93] Norouzi M, Nazari B, Miller DW. Injectable hydrogel-based drug delivery systems for local cancer therapy. Drug Discovery Today. 2016;**21**(11):1835-1849

*Colloid Science in Pharmaceutical Nanotechnology*

[83] Li VH, Wood RW, Kreuter J, Harmia T, Robinson JR. Ocular drug delivery of progesterone using nanoparticles. Journal of

Liposomes and nanoparticles: Nanosized vehicles for drug delivery in cancer. Trends in Pharmacological Sciences. 2009;**30**(11):592-599

[85] Majuru S, Oyewumi MO.

of Nanomaterials. 2015;**2015**:1

Pan Stanford; 2017. pp. 73-124

Business Media; 2008

nanoshells. Langmuir. 2005;**21**(1):403-410

2016;**6**(9):1306

2015;**16**(4):731-741

[88] De Villiers MM, Aramwit P, Kwon GS. Nanotechnology in Drug Delivery. New York: Springer Science &

[89] Zahr AS, de Villiers M, Pishko MV. Encapsulation of drug nanoparticles in self-assembled macromolecular

[90] Liu D, Yang F, Xiong F, Gu N. The smart drug delivery system and its clinical potential. Theranostics.

[91] Cui W, Li J, Decher G. Selfassembled smart Nanocarriers for targeted drug delivery. Advanced Materials. 2016;**28**(6):1302-1311

[92] Amidon S, Brown JE, Dave VS. Colon-targeted oral drug delivery systems: Design trends and approaches. AAPS PharmSciTech.

[87] Sahoo SK, Misra R, Parveen S. Nanoparticles: A boon to drug delivery, therapeutics, diagnostics and imaging. In: Nanomedicine in Cancer. Singapore:

Nanotechnology in drug development and life cycle management. In:

Nanotechnology in Drug Delivery. New York: Springer; 2009. pp. 597-619

[86] Yadollahi R, Vasilev K, Simovic S. Nanosuspension technologies for delivery of poorly soluble drugs. Journal

Microencapsulation. 1986;**3**(3):213-218

[84] Malam Y, Loizidou M, Seifalian AM.

[76] Nath S, Kaittanis C, Ramachandran V,

magnetic characterization, and sensing applications of novel dextran-coated iron oxide nanorods. Chemistry of Materials. 2009;**21**(8):1761-1767

[77] Agnihotri SA, Mallikarjuna NN, Aminabhavi TM. Recent advances on chitosan-based micro-and nanoparticles in drug delivery. Journal of Controlled

Busquets MA, Estelrich J. Chitosan (or alginate)-coated iron oxide nanoparticles: A comparative study.

Physicochemical and Engineering

[79] Inchaurraga L, Martín-Arbella N, Zabaleta V, Quincoces G, Peñuelas I, Irache JM. In vivo study of the mucuspermeating properties of PEGcoated nanoparticles following oral administration. European Journal of Pharmaceutics and Biopharmaceutics.

[80] Strehl C, Schellmann S, Maurizi L, Hofmann-Amtenbrink M, Häupl T, Hofmann H, et al. Effects of PVA-coated nanoparticles on human T helper cell activity. Toxicology Letters.

Release. 2004;**100**(1):5-28

[78] Castelló J, Gallardo M,

Colloids and Surfaces A:

Aspects. 2015;**468**:151-158

2015;**97**:280-289

2016;**245**:52-58

[81] Jaberolansar E, Kameli P,

and characterization of PVPcoated Co0. 3Zn0. 7Fe2O4 ferrite nanoparticles. Journal of Magnetism and Magnetic Materials. 2016;**404**:21-28

[82] Labhasetwar V, Dorle A. Nanoparticles—A colloidal drug delivery system for primaquine and metronidazole. Journal of Controlled

Release. 1990;**12**(2):113-119

Ahmadvand H, Salamati H. Synthesis

iron oxide nanoparticles and biocompatibility improvement by surface engineering. PLoS One.

Dalal NS, Perez JM. Synthesis,

2014;**9**(1):e85835

**30**

[94] Marwah H, Garg T, Goyal AK, Rath G. Permeation enhancer strategies in transdermal drug delivery. Drug Delivery. 2016;**23**(2):564-578

[95] Pham D-D, Fattal E, Tsapis N. Pulmonary drug delivery systems for tuberculosis treatment. International Journal of Pharmaceutics. 2015;**478**(2):517-529

[96] Chen D, Lian S, Sun J, Liu Z, Zhao F, Jiang Y, et al. Design of novel multifunctional targeting nano-carrier drug delivery system based on CD44 receptor and tumor microenvironment pH condition. Drug Delivery. 2016;**23**(3):798-803

[97] Poelma SO, Oh SS, Helmy S, Knight AS, Burnett GL, Soh HT, et al. Controlled drug release to cancer cells from modular one-photon visible light-responsive micellar system. Chemical Communications. 2016;**52**(69):10525-10528

[98] Umashankar MS, Sachdeva RK, Gulati M. Aquasomes: A promising carrier for peptides and protein delivery. Nanomedicine: Nanotechnology, Biology and Medicine. 2010;**6**(3):419-426

[99] Bianco A, Kostarelos K, Prato M. Applications of carbon nanotubes in drug delivery. Current Opinion in Chemical Biology. 2005;**9**(6):674-679

[100] Pondman KM, Bunt ND, Maijenburg AW, van Wezel RJ, Kishore U, Abelmann L, et al. Magnetic drug delivery with FePd nanowires. Journal of Magnetism and Magnetic Materials. 2015;**380**:299-306

[101] Lee S-Y, Shieh M-J. Combined photothermo-chemotherapy using gold nanoshells on drug-loaded micelles for colorectal cancer treatment. In: Colloidal Nanoparticles for Biomedical Applications XIII. California, United States: International Society for Optics and Photonics; 2018

[102] Iannazzo D, Pistone A, Celesti C, Triolo C, Patané S, Giofré SV, et al. A smart Nanovector for cancer targeted drug delivery based on Graphene quantum dots. Nanomaterials. 2019;**9**(2):282

[103] Hortelão AC, Patiño T, Perez-Jiménez A, Blanco À, Sánchez S. Enzyme-powered Nanobots enhance anticancer drug delivery. Advanced Functional Materials. 2018;**28**(25):1705086

[104] Hu CMJ, Fang RH, Zhang L. Erythrocyte-inspired delivery systems. Advanced Healthcare Materials. 2012;**1**(5):537-547

[105] Tiwari G, Tiwari R, Sriwastawa B, Bhati L, Pandey S, Pandey P, et al. Drug delivery systems: An updated review. International Journal of Pharmaceutical Investigation. 2012;**2**(1):2

[106] Singh R, Lillard JW Jr. Nanoparticle-based targeted drug delivery. Experimental and Molecular Pathology. 2009;**86**(3):215-223

[107] Kim D-H, Nikles DE, Johnson DT, Brazel CS. Heat generation of aqueously dispersed CoFe2O4 nanoparticles as heating agents for magnetically activated drug delivery and hyperthermia. Journal of Magnetism and Magnetic Materials. 2008;**320**(19):2390-2396

[108] Kim S, Kwon K, Kwon IC, Park K. Nanotechnology in drug delivery: Past, present, and future. In: Nanotechnology in Drug Delivery. New York: Springer; 2009. pp. 581-596

**33**

**Chapter 3**

Silica

**Abstract**

(1.5 × 10<sup>−</sup><sup>8</sup>

**1. Introduction**

*and Rohan Weerasooriya*

mol m<sup>−</sup><sup>2</sup>

a bidentate complex on the silica surface with 2-CP.

**Keywords:** adsorption, chlorophenol, complexation, FTIR, silica

environment as one of the main toxic organic pollutant [4, 5].

improper disposal have resulted in ground water pollution [6, 7]. 2-CP is lethal to a variety of organisms at the level of 1 mg dm<sup>−</sup><sup>3</sup>

and affect the function of the liver and immune system [3].

Adsorption Configurations of

2-Chlorophenols on Colloidal

*Lakmal Jayarathna, Nelum Karunathilake, Athula Bandara* 

Chlorophenol (CP) is the organic-chloride compound which widely used as pesticides. Industrialization and modern agriculture release a vast amount of chlorophenol to the environment. Adsorption behavior and retention of chlorophenol in the environment still not cleared. Interaction of 2-chlorophenol (2-CP) with silica surface was investigated with different reaction conditions. The study was conformed that outer-sphere complexation of 2-CP with silica surface and different surface speciation was observed at different pH conditions. Maximum adsorption

on silica surface followed the first order kinetics, and it indicates multilayer formation through capillary condensation. FTIR spectral analysis reveals the formation of

Industrialization and sophisticated agricultural techniques discharge many chlorinated compounds into the environment as primary organic pollutants [1]. Chlorophenols (CP) is designated as the most toxic organic pollutants in the list of hazardous wastes since these have a strong resistance to physical, chemical, or biological treatments [2, 3]. CPs have been used in agriculture, industry, and public health since 1920s [2]. Uses of malathion introduce 2-chlorophenol (2-CP) to the

2-CP is toxic, resistant to microbial attack, and accumulates in the food chain even from chlorophenol treated materials [6]. Accidental spillage, misuse, and

exposure of 2-CP is fatal, and the long term exposure of 2-CP may cause cancers

Although the production and the use of these are banned in some countries, chlorophenols are found in many parts of the world due to abundant usage and their environmental transportation. Owing to the toxicity and persistence of chlorophenol the controlling its levels and reducing the diffusion in the environment

[8]. Direct

) was observed around neutral pH conditions. 2-CP adsorption

#### **Chapter 3**

## Adsorption Configurations of 2-Chlorophenols on Colloidal Silica

*Lakmal Jayarathna, Nelum Karunathilake, Athula Bandara and Rohan Weerasooriya*

#### **Abstract**

Chlorophenol (CP) is the organic-chloride compound which widely used as pesticides. Industrialization and modern agriculture release a vast amount of chlorophenol to the environment. Adsorption behavior and retention of chlorophenol in the environment still not cleared. Interaction of 2-chlorophenol (2-CP) with silica surface was investigated with different reaction conditions. The study was conformed that outer-sphere complexation of 2-CP with silica surface and different surface speciation was observed at different pH conditions. Maximum adsorption (1.5 × 10<sup>−</sup><sup>8</sup> mol m<sup>−</sup><sup>2</sup> ) was observed around neutral pH conditions. 2-CP adsorption on silica surface followed the first order kinetics, and it indicates multilayer formation through capillary condensation. FTIR spectral analysis reveals the formation of a bidentate complex on the silica surface with 2-CP.

**Keywords:** adsorption, chlorophenol, complexation, FTIR, silica

#### **1. Introduction**

Industrialization and sophisticated agricultural techniques discharge many chlorinated compounds into the environment as primary organic pollutants [1]. Chlorophenols (CP) is designated as the most toxic organic pollutants in the list of hazardous wastes since these have a strong resistance to physical, chemical, or biological treatments [2, 3]. CPs have been used in agriculture, industry, and public health since 1920s [2]. Uses of malathion introduce 2-chlorophenol (2-CP) to the environment as one of the main toxic organic pollutant [4, 5].

2-CP is toxic, resistant to microbial attack, and accumulates in the food chain even from chlorophenol treated materials [6]. Accidental spillage, misuse, and improper disposal have resulted in ground water pollution [6, 7].

2-CP is lethal to a variety of organisms at the level of 1 mg dm<sup>−</sup><sup>3</sup> [8]. Direct exposure of 2-CP is fatal, and the long term exposure of 2-CP may cause cancers and affect the function of the liver and immune system [3].

Although the production and the use of these are banned in some countries, chlorophenols are found in many parts of the world due to abundant usage and their environmental transportation. Owing to the toxicity and persistence of chlorophenol the controlling its levels and reducing the diffusion in the environment

is necessary. In literature, the standard concentration levels for chlorophenols in industrial effluent and waters is set to 2 and 0.1 μg L<sup>−</sup><sup>1</sup> , respectively [9].

The fate and the diffusion of CPs depend on the neutral and ionic forms (speciation) of them. pH value of the aqueous phase governs the partition of the CP between different environments. Neutral form of CPs exhibit low solubility in water and high sorption capacity in soils, whereas the ionic form of CPs enhances the solubility in water and mobility in aqueous phase [10].

Adsorption is the major technique used for the removal or reduction of chlorinated compounds. Clays have been widely used as adsorbent due to their high specific surface area [10]. There are several reports appeared in the literature on the usage of different clay minerals as an absorbent for the removal of chlorinated pollutants [11]. These studies have proven to be very useful in describing the macroscopic nature of adsorption and adsorption kinetics. *In-situ* spectroscopic measurements further provide information on the adsorbate configurations and possible intermediates involved in some surface mediated reactions [12]. The stability of adsorbate's configuration and intermediates depends on numerous factors such as the structure of the surface and a complex formed, the coordination number of the metal atom in the complex, the thermodynamic equilibrium constant of the reaction, pH of the medium, etc. [13].

Surface properties of the adsorbents play central role in the adsorption process. The porosity of the surface and functional groups present on the surface are the main factors that govern the adsorption process [14, 15]. The efficiency of the clay mineral in the adsorption has been thoroughly investigated by several researchers [16]. Functional groups present in the organic compounds or the charge of the metal ions interest favorably with the specific properties of the mineral to enhance the adsorption. The adsorption process is influenced by many factors such as the chemical form of the adsorbate, solution pH, time of contact, adsorbate concentration, the amount of adsorbent, particle size, presence of competing adsorbates and others [17, 18].

Adsorption is one complex process involves in clay minerals with the association of contaminants. It is a mass transfer process from the aqueous phase to the solid phase accompanied by chemical and physical forces [19]. Physical characteristics of clay minerals are the governing factors in the adsorption process. Silica is reported as popular model adsorbent in the adsorption studies as it is the major constituent of natural clays by restricting the adsorption on one component. Low cost, nontoxicity, and the structural arrangements of them favor the adsorption of toxic contaminants. Silica is used as a model of soil adsorbent due to prevalence in the environment and well-characterized surface properties. The surface area of silica is an essential factor because the extent of the available surface is correlated with the surface reactivity [20].

The objective of this research is to investigate the adsorption behavior and configurations of 2-CP with silica surface using UV-visible and FT-IR spectroscopic methods.

#### **2. Materials and methods**

Colloidal silica was obtained from Fluka (Switzerland). All the other chemicals were purchased from Sigma Aldrich. Stock solutions of 2-CP and 20 g dm<sup>−</sup><sup>3</sup> suspension of silica were prepared in deionized water. The suspension was stirred for 12 hours for equilibrating. The ionic strength of the suspensions was varied in the range of 0.0001–0.01 mol dm<sup>−</sup><sup>3</sup> using 0.10 mol dm<sup>−</sup><sup>3</sup> NaNO3 solutions. All experiments were repeated for silicate suspensions with different ionic strength conditions.

**35**

**Figure 1.**

*with NaNO3.*

*Adsorption Configurations of 2-Chlorophenols on Colloidal Silica*

pattern was observed at different ionic strength conditions.

in solution pH due to the adsorption process [20–22].

vation further conformed by spectroscopic studies.

An aliquot of silica suspensions was pipetted out to Duran 100 mL sealed type laboratory glass bottle and initial solution pH values were adjusted in the pH range from 2 to 12. Known amount of 2-CP was added to silicate suspensions. Then the system was sealed and was stirred for 1 hour. The final concentration of 2-CP was determined. The effect of the initial concentration of 2-CP and effect of contact time was studied. The treated solid silica sample was recovered after the centrifugation and used for the FT-IR measurements after subsequent dying for appropriate times to eliminate water from samples. FT-IR measurements were carried out using JASCO

Variation of the adsorption density with pH is shown in the **Figure 1**. Similar

When examining the values of initial and final pH, initial pH was higher than the final pH after adsorption under acidic condition and vice-versa under basic condition. Therefore, it will predict the different types of surface interactions between 2-CP and hydroxyl groups present on silica which are responsible for the changing

Under the acidic conditions, 2-CP interacts with surface silanol groups releasing −H2O molecule to the medium resulting increase the final pH [20]. Surface interactions between 2-CP and silanol groups in the acidic condition are shown in **Figure 2**. The surface interactions between silanols and 2-CP under basic conditions are shown in **Figure 3**. Decrease of final solution pH is due to the releasing of −HCl molecule to the medium by forming a bi-dentate diphenolate complex. This obser-

*Adsorption density of 2-CP as a function of initial pH with different background ionic strength conditions* 

*DOI: http://dx.doi.org/10.5772/intechopen.88113*

FT-IR 410 spectrometer.

**3. Results and discussion**

**3.1 Effect of pH and ionic strength**

*Adsorption Configurations of 2-Chlorophenols on Colloidal Silica DOI: http://dx.doi.org/10.5772/intechopen.88113*

An aliquot of silica suspensions was pipetted out to Duran 100 mL sealed type laboratory glass bottle and initial solution pH values were adjusted in the pH range from 2 to 12. Known amount of 2-CP was added to silicate suspensions. Then the system was sealed and was stirred for 1 hour. The final concentration of 2-CP was determined. The effect of the initial concentration of 2-CP and effect of contact time was studied.

The treated solid silica sample was recovered after the centrifugation and used for the FT-IR measurements after subsequent dying for appropriate times to eliminate water from samples. FT-IR measurements were carried out using JASCO FT-IR 410 spectrometer.

#### **3. Results and discussion**

*Colloid Science in Pharmaceutical Nanotechnology*

reaction, pH of the medium, etc. [13].

others [17, 18].

surface reactivity [20].

**2. Materials and methods**

range of 0.0001–0.01 mol dm<sup>−</sup><sup>3</sup>

methods.

industrial effluent and waters is set to 2 and 0.1 μg L<sup>−</sup><sup>1</sup>

the solubility in water and mobility in aqueous phase [10].

is necessary. In literature, the standard concentration levels for chlorophenols in

The fate and the diffusion of CPs depend on the neutral and ionic forms (speciation) of them. pH value of the aqueous phase governs the partition of the CP between different environments. Neutral form of CPs exhibit low solubility in water and high sorption capacity in soils, whereas the ionic form of CPs enhances

Adsorption is the major technique used for the removal or reduction of chlorinated compounds. Clays have been widely used as adsorbent due to their high specific surface area [10]. There are several reports appeared in the literature on the usage of different clay minerals as an absorbent for the removal of chlorinated pollutants [11]. These studies have proven to be very useful in describing the macroscopic nature of adsorption and adsorption kinetics. *In-situ* spectroscopic measurements further provide information on the adsorbate configurations and possible intermediates involved in some surface mediated reactions [12]. The stability of adsorbate's configuration and intermediates depends on numerous factors such as the structure of the surface and a complex formed, the coordination number of the metal atom in the complex, the thermodynamic equilibrium constant of the

Surface properties of the adsorbents play central role in the adsorption process. The porosity of the surface and functional groups present on the surface are the main factors that govern the adsorption process [14, 15]. The efficiency of the clay mineral in the adsorption has been thoroughly investigated by several researchers [16]. Functional groups present in the organic compounds or the charge of the metal ions interest favorably with the specific properties of the mineral to enhance the adsorption. The adsorption process is influenced by many factors such as the chemical form of the adsorbate, solution pH, time of contact, adsorbate concentration, the amount of adsorbent, particle size, presence of competing adsorbates and

Adsorption is one complex process involves in clay minerals with the association of contaminants. It is a mass transfer process from the aqueous phase to the solid phase accompanied by chemical and physical forces [19]. Physical characteristics of clay minerals are the governing factors in the adsorption process. Silica is reported as popular model adsorbent in the adsorption studies as it is the major constituent of natural clays by restricting the adsorption on one component. Low cost, nontoxicity, and the structural arrangements of them favor the adsorption of toxic contaminants. Silica is used as a model of soil adsorbent due to prevalence in the environment and well-characterized surface properties. The surface area of silica is an essential factor because the extent of the available surface is correlated with the

The objective of this research is to investigate the adsorption behavior and configurations of 2-CP with silica surface using UV-visible and FT-IR spectroscopic

Colloidal silica was obtained from Fluka (Switzerland). All the other chemicals

pension of silica were prepared in deionized water. The suspension was stirred for 12 hours for equilibrating. The ionic strength of the suspensions was varied in the

using 0.10 mol dm<sup>−</sup><sup>3</sup>

ments were repeated for silicate suspensions with different ionic strength conditions.

sus-

NaNO3 solutions. All experi-

were purchased from Sigma Aldrich. Stock solutions of 2-CP and 20 g dm<sup>−</sup><sup>3</sup>

, respectively [9].

**34**

#### **3.1 Effect of pH and ionic strength**

Variation of the adsorption density with pH is shown in the **Figure 1**. Similar pattern was observed at different ionic strength conditions.

When examining the values of initial and final pH, initial pH was higher than the final pH after adsorption under acidic condition and vice-versa under basic condition. Therefore, it will predict the different types of surface interactions between 2-CP and hydroxyl groups present on silica which are responsible for the changing in solution pH due to the adsorption process [20–22].

Under the acidic conditions, 2-CP interacts with surface silanol groups releasing −H2O molecule to the medium resulting increase the final pH [20]. Surface interactions between 2-CP and silanol groups in the acidic condition are shown in **Figure 2**.

The surface interactions between silanols and 2-CP under basic conditions are shown in **Figure 3**. Decrease of final solution pH is due to the releasing of −HCl molecule to the medium by forming a bi-dentate diphenolate complex. This observation further conformed by spectroscopic studies.

**Figure 1.**

*Adsorption density of 2-CP as a function of initial pH with different background ionic strength conditions with NaNO3.*

**Figure 2.** *Proposed surface complexation of 2-CP with silica surface at acidic conditions.*

**Figure 3.** *Proposed surface complexation of 2-CP with silica surface at basic conditions.*

According to **Figure 1**, the adsorption density increased significantly from pH 2 to 7 and then decreased gradually solution pH up to 12. The maximum adsorption capacity was observed around pH 7.

Experimental results revealed that surface charge of the species present in the system at different pH conditions governs the surface interactions between the silica and adsorbate, resulting in variation in adsorption densities [23]. Further, the important parameters such as dissociation constant and the point of zero charges of adsorbent affect the adsorption amount [18]. Point of zero charge (pHZPC) of silica is 3.5 [24]. Surface charge of silica is positive below the pHZPC and negative above the pHZPC. Dissociation constant (pKa) of 2-CP is 8.10 [25–27].

According to the pKa value, 2-CP dissociated into negative charge ions over the pH range of 9–12, and it remains as neutral molecule in the pH range of 2–7.8. Further, most of the silanol groups were neutral around pH 6. Dominant silanol groups were positively charged in the pH range of 2–3 and negatively charged in the pH range of 8–12.

The dissociation of 2-CP showed a negative effect on the adsorption mechanism due to the repulsive forces between negatively charged silanol groups and 2-CP ion. Therefore, the adsorption amount was low in the pH range of 10–12. Surface interactions between the less number of undissociated 2-CP and silica molecules showed a significant amount of adsorption even under the extreme acidic and basic conditions. However, the adsorption density was higher in the acidic region than in the alkaline area because the surface interactions were feasible due to the absence of molecules. Favorable surface interactions between neutral 2-CP and silanol groups showed a higher amount of adsorption density around pH 6 [28].

Furthermore, according to **Figure 1**, it shows that adsorption density was inversely proportional to the ionic strength of the medium. Effect of ionic strength on the adsorption process indicated that adsorption on to variable charge mineral surfaces could form outer-sphere complexes via electrostatic interactions [20, 29].

**37**

**Figure 4.**

*Adsorption Configurations of 2-Chlorophenols on Colloidal Silica*

Outer-sphere complexation is sensitive to the changes of ionic strength due to the competition with counter ions in the background electrolytes [30]. Competition between counter ions and adsorbate was more significant at higher ionic strength conditions than at lower ionic strength conditions. These facts prove the formation

Adsorption configuration between surface silanols groups and 2-CP at different pH conditions further confirmed by FT-IR spectral studies. **Figure 4(a)** shows the FT-IR spectra of untreated silica along with the adsorbed 2-CP at different solution pH conditions. Spectrum is divided into two parts of 500–1800 cm<sup>−</sup><sup>1</sup>

In the spectrum A, the bands for Si-OH bending modes at ~1080–1270 cm<sup>−</sup><sup>1</sup>

could be attributed to the H-O-H bending vibration of physically

. The spectrum of untreated silica is shown in line (A).

were observed. In addition to these characteristic bands, a band appeared at

indicates that the presence of isolated OH groups on the surface [32]. It was observed that the adsorption of 2-CP onto silica surface influence the IR spectrum of the untreated silica. For better comparison, IR spectra of silica surface treated with 2-CP at pH 5 and 9 are shown in lines (B) and (C), respectively, in **Figure 4(a)**. These spectra were measured after 3 hour equilibration time of the silica with 2-CP at respective pH. Upon adsorption of 2-CP, new bands

of untreated silica showed significant losses in their intensities. These observations suggest that the 2-CP chemisorbed on the surface [33, 34]. This behavior of chemisorption is further explained in **Figure 4(b)** where the difference

*(a) FTIR spectra of (A) bare silica, (B) silica treated with 2-CP at pH 5 and (C) silica treated with 2-CP at pH 9. The bare silica samples prepare at pH 5 and 9 gave coincident spectra. All the spectra are plotted in the* 

*region. (b) Difference spectrum at pH 9. The positive bands are characteristic for 2-CP on the surface while* 

*same scale for direct comparison. Scale is broken between 1800 and 2750 cm<sup>−</sup><sup>1</sup>*

*negative bands indicate the loss of surface sites due to chemisorption of 2-CP.*

adsorbed water as the broad band further supports this at ~3475 cm<sup>−</sup><sup>1</sup>

for simplicity as no bands were observed between 1800 and

is typical for isolated O-H stretching vibration, and it

and Si-O stretching mode at ~915 cm<sup>−</sup><sup>1</sup>

with an observation of complete

while all the other bands

 *as no bands were observed in the* 

,

[21, 31].

,

of outer-sphere complexes upon the adsorption of 2-CP on silica [30].

*DOI: http://dx.doi.org/10.5772/intechopen.88113*

Si-OH deformation mode at ~811 cm<sup>−</sup><sup>1</sup>

appeared at 1280, 1482 and ~3030–3070 cm<sup>−</sup><sup>1</sup>

disappearance of the isolated O-H groups at 3743 cm<sup>−</sup><sup>1</sup>

**3.2 FTIR investigation**

and 2800–4000 cm<sup>−</sup><sup>1</sup>

The band at 3743 cm<sup>−</sup><sup>1</sup>

2800 cm<sup>−</sup><sup>1</sup>

~1637 cm<sup>−</sup><sup>1</sup>

Outer-sphere complexation is sensitive to the changes of ionic strength due to the competition with counter ions in the background electrolytes [30]. Competition between counter ions and adsorbate was more significant at higher ionic strength conditions than at lower ionic strength conditions. These facts prove the formation of outer-sphere complexes upon the adsorption of 2-CP on silica [30].

#### **3.2 FTIR investigation**

*Colloid Science in Pharmaceutical Nanotechnology*

capacity was observed around pH 7.

**Figure 3.**

**Figure 2.**

Dissociation constant (pKa) of 2-CP is 8.10 [25–27].

*Proposed surface complexation of 2-CP with silica surface at basic conditions.*

*Proposed surface complexation of 2-CP with silica surface at acidic conditions.*

According to **Figure 1**, the adsorption density increased significantly from pH 2 to 7 and then decreased gradually solution pH up to 12. The maximum adsorption

Experimental results revealed that surface charge of the species present in the system at different pH conditions governs the surface interactions between the silica and adsorbate, resulting in variation in adsorption densities [23]. Further, the important parameters such as dissociation constant and the point of zero charges of adsorbent affect the adsorption amount [18]. Point of zero charge (pHZPC) of silica is 3.5 [24]. Surface charge of silica is positive below the pHZPC and negative above the pHZPC.

According to the pKa value, 2-CP dissociated into negative charge ions over the pH range of 9–12, and it remains as neutral molecule in the pH range of 2–7.8. Further, most of the silanol groups were neutral around pH 6. Dominant silanol groups were positively charged in the pH range of 2–3 and negatively charged in the pH range of 8–12. The dissociation of 2-CP showed a negative effect on the adsorption mechanism

due to the repulsive forces between negatively charged silanol groups and 2-CP ion. Therefore, the adsorption amount was low in the pH range of 10–12. Surface interactions between the less number of undissociated 2-CP and silica molecules showed a significant amount of adsorption even under the extreme acidic and basic conditions. However, the adsorption density was higher in the acidic region than in the alkaline area because the surface interactions were feasible due to the absence of molecules. Favorable surface interactions between neutral 2-CP and silanol groups

Furthermore, according to **Figure 1**, it shows that adsorption density was inversely proportional to the ionic strength of the medium. Effect of ionic strength on the adsorption process indicated that adsorption on to variable charge mineral surfaces could form outer-sphere complexes via electrostatic interactions [20, 29].

showed a higher amount of adsorption density around pH 6 [28].

**36**

Adsorption configuration between surface silanols groups and 2-CP at different pH conditions further confirmed by FT-IR spectral studies. **Figure 4(a)** shows the FT-IR spectra of untreated silica along with the adsorbed 2-CP at different solution pH conditions. Spectrum is divided into two parts of 500–1800 cm<sup>−</sup><sup>1</sup> , and 2800–4000 cm<sup>−</sup><sup>1</sup> for simplicity as no bands were observed between 1800 and 2800 cm<sup>−</sup><sup>1</sup> . The spectrum of untreated silica is shown in line (A).

In the spectrum A, the bands for Si-OH bending modes at ~1080–1270 cm<sup>−</sup><sup>1</sup> , Si-OH deformation mode at ~811 cm<sup>−</sup><sup>1</sup> and Si-O stretching mode at ~915 cm<sup>−</sup><sup>1</sup> were observed. In addition to these characteristic bands, a band appeared at ~1637 cm<sup>−</sup><sup>1</sup> could be attributed to the H-O-H bending vibration of physically adsorbed water as the broad band further supports this at ~3475 cm<sup>−</sup><sup>1</sup> [21, 31]. The band at 3743 cm<sup>−</sup><sup>1</sup> is typical for isolated O-H stretching vibration, and it indicates that the presence of isolated OH groups on the surface [32]. It was observed that the adsorption of 2-CP onto silica surface influence the IR spectrum of the untreated silica. For better comparison, IR spectra of silica surface treated with 2-CP at pH 5 and 9 are shown in lines (B) and (C), respectively, in **Figure 4(a)**. These spectra were measured after 3 hour equilibration time of the silica with 2-CP at respective pH. Upon adsorption of 2-CP, new bands appeared at 1280, 1482 and ~3030–3070 cm<sup>−</sup><sup>1</sup> with an observation of complete disappearance of the isolated O-H groups at 3743 cm<sup>−</sup><sup>1</sup> while all the other bands of untreated silica showed significant losses in their intensities. These observations suggest that the 2-CP chemisorbed on the surface [33, 34]. This behavior of chemisorption is further explained in **Figure 4(b)** where the difference

#### **Figure 4.**

*(a) FTIR spectra of (A) bare silica, (B) silica treated with 2-CP at pH 5 and (C) silica treated with 2-CP at pH 9. The bare silica samples prepare at pH 5 and 9 gave coincident spectra. All the spectra are plotted in the same scale for direct comparison. Scale is broken between 1800 and 2750 cm<sup>−</sup><sup>1</sup> as no bands were observed in the region. (b) Difference spectrum at pH 9. The positive bands are characteristic for 2-CP on the surface while negative bands indicate the loss of surface sites due to chemisorption of 2-CP.*

spectrum (2-CP adsorbed—bare silica) is depicted. Negative bands at ~811, 915, 1270, 1637, 3475 and 3743 cm<sup>−</sup><sup>1</sup> suggest the loss of original nature of Si-O(H) moieties upon adsorption of 2-CP while the positive bands appeared at ~1280, 1482 and 3070 cm<sup>−</sup><sup>1</sup> clearly shows the presence of 2-CP on the surface [21]. The disappearance of 3743 cm<sup>−</sup><sup>1</sup> bands indicated that the isolated hydroxyl groups are one of the major adsorption sites for 2-CP. Reduced intensities of other characteristic bands of silica further suggest the interaction of 2-CP with the surface. The new bands appeared at 1280, 1482 and 3050 cm<sup>−</sup><sup>1</sup> are assigned to the C-O stretching, C〓C stretching of the benzene ring, and aromatic C-H stretching modes, respectively, of 2-CP [31]. It should note here that the 1280 cm<sup>−</sup><sup>1</sup> band appeared at pH 9 is more intense compared to that observed at pH 5 even though the amount adsorbed (64%) was lesser than that observed at pH 5 (74%) [33, 34].

The IR observations can further explain the variation of solution pH with the adsorption. **Figure 5(a)** shows the results in the 1400–1800 cm<sup>−</sup><sup>1</sup> region for the untreated (bare: dash-dot line) silica, and silica treated with 2-CP at pH 5 (line A) and 9 (line B).

As described earlier, the intensity of the band due to H-O-H bending mode of silica at 1637 cm<sup>−</sup><sup>1</sup> decreased in intensity and shifted to around 1630 cm<sup>−</sup><sup>1</sup> upon adsorption of 2-CP in both cases. When the pH of the medium was 9, the band at 1637 cm<sup>−</sup><sup>1</sup> lost its intensity with the appearance of a new band at 1607 cm<sup>−</sup><sup>1</sup> . Also, a clear change was observed in the band at ~1482 cm<sup>−</sup><sup>1</sup> . A new band appeared at 1495 cm<sup>−</sup><sup>1</sup> with a remaining shoulder at ~1477 cm<sup>−</sup><sup>1</sup> and a second shoulder at ~1452 cm<sup>−</sup><sup>1</sup> was observed. These observations suggest that different type of bonding species are involved in these two pH conditions. The new band appeared at 1495 cm<sup>−</sup><sup>1</sup> along with the shift in the band at 1637–1607 cm<sup>−</sup><sup>1</sup> reveal the formation of catechol type intermediate [35, 36]. The bands at 1495 cm<sup>−</sup><sup>1</sup> can be attributed to the C-C stretch of the above catechol type intermediate and that the appearance of strong band at 1280 cm<sup>−</sup><sup>1</sup> (**Figure 4**, line C) might indicate the presence of moreoriented C-O bonding in the same species of the above. The shift in 1482 cm<sup>−</sup><sup>1</sup> band

#### **Figure 5.**

*FTIR spectra in 1400–1800 cm<sup>−</sup><sup>1</sup> region (a) 2-CP and (b) 4-CP, bare silica: dashed-dot line, (A) silica treated with 2 and 4 CP at pH 5 and (B) silica treated with 2 and 4 CPs at pH 9. The bare silica samples prepare at pH 5 and 9 gave coincident spectra. All the spectra are plotted in the same scale for direct comparison.*

**39**

**Funding**

road, Kandy.

*Adsorption Configurations of 2-Chlorophenols on Colloidal Silica*

and another shoulder peak at ~455 cm<sup>−</sup><sup>1</sup>

did not appear. Further, the band shift at 1637 cm<sup>−</sup><sup>1</sup>

species are proved by the observation of a band at ~1600 and 1494 cm<sup>−</sup><sup>1</sup>

electronic environment of the benzene ring due to the formation of catechol intermediate in which that can be in bi-dentate or bridging configuration to the silica surface. The experiments done with 4-CP further confirmed the formation of this intermediate and the results are shown in **Figure 5(b)**. The adsorption of 4-CPon silica at different pHs showed quite similar spectra and the bands at 1607 and

cannot form catechol type intermediate upon adsorption hence giving no bands around the above frequencies. Study on the adsorption of 2-CP vapor on fused silica at high temperature revealed that the formation of catechol type intermediate species by the bonding of 2-CP via Cl atom and phenolic oxygen and formation of such

Though the pH 9 of the medium is higher than pKa of 2-CP (8.52) the above observations clearly show the supportive information for the proposed adsorbed species. When the pH is higher than pKa, anionic species formed may have a high tendency towards interacting with silica by the elimination of H2O and HCl molecules [33]. However, previous studies on the adsorption of 2-CP on fly ash and Ca-montmorillonite showed the reduction in the adsorption capacity when the pH was higher than pKa where the dissociated organic molecules experience the repulsion from the negatively charged surface [38]. In the present study, the amount adsorbed at pH 5 was ~74% while that at pH 9 was 64%. Despite that repulsion and ~10% reduction in the adsorption, the step of the elimination of Cl atom may make some favorable path for the remaining (or dissociated) 2-CP to interact with the Si-O sites [39].

Adsorption of 2-CP on silica surface was examined under different pH condi-

Effect of ionic strength on the adsorption was significant as the adsorption capacity was inversely proportional to the ionic strength of the medium. Experimental results confirmed the formation of outer-sphere complexes during the adsorption process. FTIR spectroscopic studies revealed the direct interaction between 2CP and silica via catechol type bidentate complex by eliminating HCl while the experiments with 4CP further confirmed the formation of such an adsorbate configuration. In the future, these observations can also apply to identify degradation pathways of 2-CP in

All the authors declare that there are no potential conflicts of interest in any

This study was funded by National Institute of Fundamental Studies, Hanthana

observed at pH 7. There are different adsorbed species were predicted in different pH conditions. The interaction between colloidal silica (SiO2) and 2-CP was investigated in an aqueous medium with the emphasis of Fourier Transform infrared

mol m<sup>−</sup><sup>2</sup>

tions. The maximum adsorption capacity of 1.5 × 10<sup>−</sup><sup>8</sup>

natural soil system in different environmental conditions.

indicate the changes in the

was negligible. 4-CP

on silica surface was

[25, 35, 37].

*DOI: http://dx.doi.org/10.5772/intechopen.88113*

to 1477 cm<sup>−</sup><sup>1</sup>

1495 cm<sup>−</sup><sup>1</sup>

**4. Conclusions**

(FT-IR) spectroscopy.

**Conflicts of interest**

financial or nonfinancial.

#### *Adsorption Configurations of 2-Chlorophenols on Colloidal Silica DOI: http://dx.doi.org/10.5772/intechopen.88113*

to 1477 cm<sup>−</sup><sup>1</sup> and another shoulder peak at ~455 cm<sup>−</sup><sup>1</sup> indicate the changes in the electronic environment of the benzene ring due to the formation of catechol intermediate in which that can be in bi-dentate or bridging configuration to the silica surface. The experiments done with 4-CP further confirmed the formation of this intermediate and the results are shown in **Figure 5(b)**. The adsorption of 4-CPon silica at different pHs showed quite similar spectra and the bands at 1607 and 1495 cm<sup>−</sup><sup>1</sup> did not appear. Further, the band shift at 1637 cm<sup>−</sup><sup>1</sup> was negligible. 4-CP cannot form catechol type intermediate upon adsorption hence giving no bands around the above frequencies. Study on the adsorption of 2-CP vapor on fused silica at high temperature revealed that the formation of catechol type intermediate species by the bonding of 2-CP via Cl atom and phenolic oxygen and formation of such species are proved by the observation of a band at ~1600 and 1494 cm<sup>−</sup><sup>1</sup> [25, 35, 37].

Though the pH 9 of the medium is higher than pKa of 2-CP (8.52) the above observations clearly show the supportive information for the proposed adsorbed species. When the pH is higher than pKa, anionic species formed may have a high tendency towards interacting with silica by the elimination of H2O and HCl molecules [33]. However, previous studies on the adsorption of 2-CP on fly ash and Ca-montmorillonite showed the reduction in the adsorption capacity when the pH was higher than pKa where the dissociated organic molecules experience the repulsion from the negatively charged surface [38]. In the present study, the amount adsorbed at pH 5 was ~74% while that at pH 9 was 64%. Despite that repulsion and ~10% reduction in the adsorption, the step of the elimination of Cl atom may make some favorable path for the remaining (or dissociated) 2-CP to interact with the Si-O sites [39].

#### **4. Conclusions**

*Colloid Science in Pharmaceutical Nanotechnology*

1270, 1637, 3475 and 3743 cm<sup>−</sup><sup>1</sup>

disappearance of 3743 cm<sup>−</sup><sup>1</sup>

1482 and 3070 cm<sup>−</sup><sup>1</sup>

pH 5 (74%) [33, 34].

1280 cm<sup>−</sup><sup>1</sup>

and 9 (line B).

1637 cm<sup>−</sup><sup>1</sup>

at 1495 cm<sup>−</sup><sup>1</sup>

~1452 cm<sup>−</sup><sup>1</sup>

1495 cm<sup>−</sup><sup>1</sup>

silica at 1637 cm<sup>−</sup><sup>1</sup>

strong band at 1280 cm<sup>−</sup><sup>1</sup>

spectrum (2-CP adsorbed—bare silica) is depicted. Negative bands at ~811, 915,

moieties upon adsorption of 2-CP while the positive bands appeared at ~1280,

are one of the major adsorption sites for 2-CP. Reduced intensities of other characteristic bands of silica further suggest the interaction of 2-CP with the

to the C-O stretching, C〓C stretching of the benzene ring, and aromatic C-H stretching modes, respectively, of 2-CP [31]. It should note here that the

pH 5 even though the amount adsorbed (64%) was lesser than that observed at

The IR observations can further explain the variation of solution pH with the

untreated (bare: dash-dot line) silica, and silica treated with 2-CP at pH 5 (line A)

As described earlier, the intensity of the band due to H-O-H bending mode of

lost its intensity with the appearance of a new band at 1607 cm<sup>−</sup><sup>1</sup>

adsorption of 2-CP in both cases. When the pH of the medium was 9, the band at

ing species are involved in these two pH conditions. The new band appeared at

oriented C-O bonding in the same species of the above. The shift in 1482 cm<sup>−</sup><sup>1</sup>

the C-C stretch of the above catechol type intermediate and that the appearance of

decreased in intensity and shifted to around 1630 cm<sup>−</sup><sup>1</sup>

was observed. These observations suggest that different type of bond-

(**Figure 4**, line C) might indicate the presence of more-

 *region (a) 2-CP and (b) 4-CP, bare silica: dashed-dot line, (A) silica treated* 

*with 2 and 4 CP at pH 5 and (B) silica treated with 2 and 4 CPs at pH 9. The bare silica samples prepare at pH 5 and 9 gave coincident spectra. All the spectra are plotted in the same scale for direct comparison.*

surface. The new bands appeared at 1280, 1482 and 3050 cm<sup>−</sup><sup>1</sup>

adsorption. **Figure 5(a)** shows the results in the 1400–1800 cm<sup>−</sup><sup>1</sup>

with a remaining shoulder at ~1477 cm<sup>−</sup><sup>1</sup>

of catechol type intermediate [35, 36]. The bands at 1495 cm<sup>−</sup><sup>1</sup>

along with the shift in the band at 1637–1607 cm<sup>−</sup><sup>1</sup>

a clear change was observed in the band at ~1482 cm<sup>−</sup><sup>1</sup>

suggest the loss of original nature of Si-O(H)

bands indicated that the isolated hydroxyl groups

are assigned

region for the

. A new band appeared

and a second shoulder at

reveal the formation

can be attributed to

upon

. Also,

band

clearly shows the presence of 2-CP on the surface [21]. The

band appeared at pH 9 is more intense compared to that observed at

**38**

**Figure 5.**

*FTIR spectra in 1400–1800 cm<sup>−</sup><sup>1</sup>*

Adsorption of 2-CP on silica surface was examined under different pH conditions. The maximum adsorption capacity of 1.5 × 10<sup>−</sup><sup>8</sup> mol m<sup>−</sup><sup>2</sup> on silica surface was observed at pH 7. There are different adsorbed species were predicted in different pH conditions. The interaction between colloidal silica (SiO2) and 2-CP was investigated in an aqueous medium with the emphasis of Fourier Transform infrared (FT-IR) spectroscopy.

Effect of ionic strength on the adsorption was significant as the adsorption capacity was inversely proportional to the ionic strength of the medium. Experimental results confirmed the formation of outer-sphere complexes during the adsorption process. FTIR spectroscopic studies revealed the direct interaction between 2CP and silica via catechol type bidentate complex by eliminating HCl while the experiments with 4CP further confirmed the formation of such an adsorbate configuration. In the future, these observations can also apply to identify degradation pathways of 2-CP in natural soil system in different environmental conditions.

#### **Conflicts of interest**

All the authors declare that there are no potential conflicts of interest in any financial or nonfinancial.

#### **Funding**

This study was funded by National Institute of Fundamental Studies, Hanthana road, Kandy.

### **Abbreviation**

2-CP 2-chlorophenol

### **Author details**

Lakmal Jayarathna1 \*, Nelum Karunathilake2 , Athula Bandara3 and Rohan Weerasooriya1

1 National Institute of Fundamental Studies, Kandy, Sri Lanka

2 Postgraduate Institute of Science, University of Peradeniya, Peradeniya, Sri Lanka

3 Department of Chemistry, University of Peradeniya, Peradeniya, Sri Lanka

\*Address all correspondence to: lakmalipj@yahoo.co.uk

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

**41**

*Adsorption Configurations of 2-Chlorophenols on Colloidal Silica*

[7] Yousef RI, El-Eswed B. The effect of pH on the adsorption of phenol and chlorophenols onto natural zeolite. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 2009;**334**(1):92-99. DOI: 10.1016/j.colsurfa.2008.10.004

[8] Gonzalez JF, Hu W-S. Effect of glutamate on the degradation of pentachlorophenol by *Flavobacterium* sp. Applied Microbiology and Biotechnology. 1991;**35**(1):100-104.

[9] Bazrafshan E, Mostafapour FK, Jafari Mansourian H. Phenolic compounds: Health effects and its removal from aqueous environments by low cost adsorbents. Health Scope.

[10] Murcia MD, Gomez M, Gomez E, Bodalo A, Gomez JL, Hidalgo AM. Assessing combination treatment, enzymatic oxidation and ultrafiltration

4-chlorophenol removal: Experimental and modeling. Journal of Membrane Science. 2009;**342**(1):198-207. DOI: 10.1016/j.memsci.2009.06.037

[11] Ali I, Asim M, Khan TA. Low cost adsorbents for the removal of organic pollutants from wastewater. Journal of Environmental Management. 2012;**113**:170-183. DOI: 10.1016/j.

[12] Li J, Cui H, Song X, Zhang G, Wang X, Song Q, et al. Adsorption and intercalation of organic pollutants and heavy metal ions into MgAl-LDHs nanosheets with high capacity. RSC Advances. 2016;**6**(95):92402-92410.

[13] Wang C, Ma R, Wu Q, Sun M, Wang Z. Magnetic porous carbon as an adsorbent for the enrichment of chlorophenols from water and

in a membrane bioreactor, for

jenvman.2012.08.028

DOI: 10.1039/c6ra18783h

DOI: 10.1007/bf00180644

2013;**2**(2):65-66

*DOI: http://dx.doi.org/10.5772/intechopen.88113*

[1] Butter TJ, Evison LM, Hancock IC, Holland FS, Matis KA, Philipson A, et al. The removal and recovery of cadmium from dilute aqueous solutions by biosorption and electrolysis at laboratory scale. Water Research. 1998;**32**(2):400-406. DOI: 10.1016/

[2] Zheng S, Yang Z, Jo DH, Park YH. Removal of chlorophenols from groundwater by chitosan sorption. Water Research. 2004;**38**(9):2315-2322. DOI: 10.1016/j.watres.2004.02.010

[4] Lacorte S, Viana P, Guillamon M, Tauler R, Vinhas T, Barcelo D. Main findings and conclusions of the implementation of directive 76/464/ CEE concerning the monitoring of organic pollutants in surface waters (Portugal, April 1999-May 2000). Journal of Environmental Monitoring. 2001;**3**(5):475-482. DOI: 10.1039/

[5] Zhou L-C, Meng X-G, Fu J-W, Yang Y-C, Yang P, Mi C. Highly efficient adsorption of chlorophenols onto chemically modified chitosan. Applied Surface Science. 2014;**292**:735-741. DOI:

10.1016/j.apsusc.2013.12.041

DOI: 10.1007/bf00505829

[6] Edgehill RU, Finn RK. Isolation, characterization and growth kinetics of bacteria metabolizing pentachlorophenol. European Journal of Applied Microbiology and Biotechnology. 1982;**16**(4):179-184.

S0043-1354(97)00273-X

[3] Yu J-Y, Shin M-Y, Noh J-H, Seo J-J. Adsorption of phenol and chlorophenols on hexadecyltrimethylammoniumand tetramethylammoniummontmorillonite from aqueous solutions. Geosciences Journal. 2004;**8**(2):191. DOI: 10.1007/

bf02910195

b104832p

**References**

*Adsorption Configurations of 2-Chlorophenols on Colloidal Silica DOI: http://dx.doi.org/10.5772/intechopen.88113*

#### **References**

*Colloid Science in Pharmaceutical Nanotechnology*

2-CP 2-chlorophenol

**Abbreviation**

**40**

**Author details**

Lakmal Jayarathna1

and Rohan Weerasooriya1

\*, Nelum Karunathilake2

1 National Institute of Fundamental Studies, Kandy, Sri Lanka

\*Address all correspondence to: lakmalipj@yahoo.co.uk

provided the original work is properly cited.

2 Postgraduate Institute of Science, University of Peradeniya, Peradeniya, Sri Lanka

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

3 Department of Chemistry, University of Peradeniya, Peradeniya, Sri Lanka

, Athula Bandara3

[1] Butter TJ, Evison LM, Hancock IC, Holland FS, Matis KA, Philipson A, et al. The removal and recovery of cadmium from dilute aqueous solutions by biosorption and electrolysis at laboratory scale. Water Research. 1998;**32**(2):400-406. DOI: 10.1016/ S0043-1354(97)00273-X

[2] Zheng S, Yang Z, Jo DH, Park YH. Removal of chlorophenols from groundwater by chitosan sorption. Water Research. 2004;**38**(9):2315-2322. DOI: 10.1016/j.watres.2004.02.010

[3] Yu J-Y, Shin M-Y, Noh J-H, Seo J-J. Adsorption of phenol and chlorophenols on hexadecyltrimethylammoniumand tetramethylammoniummontmorillonite from aqueous solutions. Geosciences Journal. 2004;**8**(2):191. DOI: 10.1007/ bf02910195

[4] Lacorte S, Viana P, Guillamon M, Tauler R, Vinhas T, Barcelo D. Main findings and conclusions of the implementation of directive 76/464/ CEE concerning the monitoring of organic pollutants in surface waters (Portugal, April 1999-May 2000). Journal of Environmental Monitoring. 2001;**3**(5):475-482. DOI: 10.1039/ b104832p

[5] Zhou L-C, Meng X-G, Fu J-W, Yang Y-C, Yang P, Mi C. Highly efficient adsorption of chlorophenols onto chemically modified chitosan. Applied Surface Science. 2014;**292**:735-741. DOI: 10.1016/j.apsusc.2013.12.041

[6] Edgehill RU, Finn RK. Isolation, characterization and growth kinetics of bacteria metabolizing pentachlorophenol. European Journal of Applied Microbiology and Biotechnology. 1982;**16**(4):179-184. DOI: 10.1007/bf00505829

[7] Yousef RI, El-Eswed B. The effect of pH on the adsorption of phenol and chlorophenols onto natural zeolite. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 2009;**334**(1):92-99. DOI: 10.1016/j.colsurfa.2008.10.004

[8] Gonzalez JF, Hu W-S. Effect of glutamate on the degradation of pentachlorophenol by *Flavobacterium* sp. Applied Microbiology and Biotechnology. 1991;**35**(1):100-104. DOI: 10.1007/bf00180644

[9] Bazrafshan E, Mostafapour FK, Jafari Mansourian H. Phenolic compounds: Health effects and its removal from aqueous environments by low cost adsorbents. Health Scope. 2013;**2**(2):65-66

[10] Murcia MD, Gomez M, Gomez E, Bodalo A, Gomez JL, Hidalgo AM. Assessing combination treatment, enzymatic oxidation and ultrafiltration in a membrane bioreactor, for 4-chlorophenol removal: Experimental and modeling. Journal of Membrane Science. 2009;**342**(1):198-207. DOI: 10.1016/j.memsci.2009.06.037

[11] Ali I, Asim M, Khan TA. Low cost adsorbents for the removal of organic pollutants from wastewater. Journal of Environmental Management. 2012;**113**:170-183. DOI: 10.1016/j. jenvman.2012.08.028

[12] Li J, Cui H, Song X, Zhang G, Wang X, Song Q, et al. Adsorption and intercalation of organic pollutants and heavy metal ions into MgAl-LDHs nanosheets with high capacity. RSC Advances. 2016;**6**(95):92402-92410. DOI: 10.1039/c6ra18783h

[13] Wang C, Ma R, Wu Q, Sun M, Wang Z. Magnetic porous carbon as an adsorbent for the enrichment of chlorophenols from water and

peach juice samples. Journal of Chromatography A. 2014;**1361**:60-66. DOI: 10.1016/j.chroma.2014.08.002

[14] Zhang X, Bai R. Mechanisms and kinetics of humic acid adsorption onto chitosan-coated granules. Journal of Colloid and Interface Science. 2003;**264**(1):30-38. DOI: 10.1016/ S0021-9797(03)00393-X

[15] Farrah H, Pickering W. The sorption of lead and cadmium species by clay minerals. Australian Journal of Chemistry. 1977;**30**(7):1417-1422. DOI: 10.1071/CH9771417

[16] Feddal I, Ramdani A, Taleb S, Gaigneaux EM, Batis N, Ghaffour N. Adsorption capacity of methylene blue, an organic pollutant, by montmorillonite clay. Desalination and Water Treatment. 2014;**52**(13-15):2654-2661. DOI: 10.1080/19443994.2013.865566

[17] Johnson BB. Effect of pH, temperature, and concentration on the adsorption of cadmium on goethite. Environmental Science & Technology. 1990;**24**(1):112-118. DOI: 10.1021/ es00071a014

[18] Jarvis SC, Jones LHP. The contents and sorption of cadmium in some agricultural soils of England and Wales. Journal of Soil Science. 1980;**31**(3): 469-479. DOI: 10.1111/j.1365-2389.1980. tb02096.x

[19] Weerasooriya R, Wickramarathne HUS, Dharmagunawardhane HA. Surface complexation modeling of fluoride adsorption onto kaolinite. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 1998;**144**(1):267-273. DOI: 10.1016/S0927-7757(98)00646-3

[20] Sayari A, Hamoudi S, Yang Y. Applications of pore-expanded mesoporous silica. 1. Removal of heavy metal cations and organic pollutants

from wastewater. Chemistry of Materials. 2005;**17**(1):212-216. DOI: 10.1021/cm048393e

[21] Zhang L, Zhang B, Wu T, Sun D, Li Y. Adsorption behavior and mechanism of chlorophenols onto organoclays in aqueous solution. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 2015;**484**:118-129. DOI: 10.1016/j.colsurfa.2015.07.055

[22] Wahab HS, Bredow T, Aliwi SM. A computational study on the adsorption and ring cleavage of para-chlorophenol on anatase TiO2 surface. Surface Science. 2009;**603**(4):664-669. DOI: 10.1016/j.susc.2009.01.001

[23] Vaishya RC, Gupta SK. Modelling arsenic(III) adsorption from water by sulfate-modified iron oxide-coated sand (SMIOCS). Journal of Chemical Technology & Biotechnology. 2003;**78**(1):73-80. DOI: 10.1002/jctb.745

[24] Cho GS, Lee D-H, Lim HM, Lee S-H, Kim C, Kim DS. Characterization of surface charge and zeta potential of colloidal silica prepared by various methods. Korean Journal of Chemical Engineering. 2014;**31**(11):2088-2093. DOI: 10.1007/s11814-014-0112-5

[25] Soltani T, Lee B-K. Mechanism of highly efficient adsorption of 2-chlorophenol onto ultrasonic graphene materials: Comparison and equilibrium. Journal of Colloid and Interface Science. 2016;**481**:168-180. DOI: 10.1016/j.jcis.2016.07.049

[26] Shirzad-Siboni M, Jafari S-J, Farrokhi M, Yang JK. Removal of phenol from aqueous solutions by activated red mud: Equilibrium and kinetics studies. Environmental Engineering Research. 2013;**18**(4):247-252. DOI: 10.4491/ eer.2013.18.4.247

[27] Uchida M, Okuwaki A. UV-vis spectrophotometric determination of the dissociation constants for

**43**

*Adsorption Configurations of 2-Chlorophenols on Colloidal Silica*

study. ChemCatChem. 2017;**9**(3):481- 491. DOI: 10.1002/cctc.201601069

[34] Alderman SL, Dellinger B. FTIR investigation of 2-chlorophenol chemisorption on a silica surface from 200 to 500°C. The Journal of Physical Chemistry A. 2005;**109**(34):7725-7731.

DOI: 10.1021/jp051071t

[35] Bardakçı B. Monitoring of

Monitoring and Assessment. 2009;**148**(1):353-357. DOI: 10.1007/

[36] Lochab B, Shukla S, Varma IK. Naturally occurring phenolic sources: Monomers and polymers. RSC Advances. 2014;**4**(42):21712-21752. DOI:

[37] Bustos-Ramírez K, Barrera-Díaz CE, De Icaza-Herrera M, Martínez-Hernández AL, Natividad-Rangel R, Velasco-Santos C. 4-chlorophenol removal from water using graphite and graphene oxides as photocatalysts. Journal of Environmental Health Science and Engineering. 2015;**13**(1):33. DOI: 10.1186/s40201-015-0184-0

[38] Yu J-Y, Shin M-Y, Noh J-H, Seo J-J. Adsorption of phenol and chlorophenols on Ca-montmorillonite in aqueous solutions. Geosciences Journal. 2004;**8**(2):185-189. DOI: 10.1007/

[39] Hamdaoui O, Naffrechoux E. Modeling of adsorption isotherms of phenol and chlorophenols onto granular activated carbon: Part I. Two-parameter models and equations allowing determination of thermodynamic parameters. Journal of Hazardous Materials. 2007;**147**(1):381-394. DOI: https://doi. org/10.1016/j.jhazmat.2007.01.021

bf02910194

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10.1039/c4ra00181h

monochlorophenols adsorbed on metal (Cu and Zn) supported pumice by infrared spectroscopy. Environmental

*DOI: http://dx.doi.org/10.5772/intechopen.88113*

monochlorophenols in aqueous solution at elevated temperatures. Journal of Solution Chemistry. 2003;**32**(1):19-39.

DOI: 10.1023/a:1022980614320

[29] Hayes KF, Papelis C, Leckie JO. Modeling ionic strength effects on anion adsorption at hydrous oxide/solution interfaces. Journal of Colloid and Interface Science. 1988;**125**(2):717-726. DOI: 10.1016/0021-9797(88)90039-2

[30] Cea M, Seaman JC, Jara AA, Mora ML, Diez MC. Describing chlorophenol

[31] Li Y, Li X, Dong C, Li Y, Jin P, Qi J. Selective recognition and removal of chlorophenols from aqueous solution using molecularly imprinted polymer prepared by reversible addition-fragmentation chain transfer polymerization. Biosensors and Bioelectronics. 2009;**25**(2):306-312. DOI: 10.1016/j.bios.2009.07.001

[32] Song D, Li J, Cai Q. In situ diffuse reflectance FTIR study of CO adsorbed on a cobalt catalyst supported by silica with different pore sizes. The Journal of Physical Chemistry C. 2007;**111**(51):18970-18979. DOI:

[33] Mosallanejad S, Dlugogorski BZ, Kennedy EM, Stockenhuber M. Adsorption of 2-chlorophenol on the surface of silica- and aluminasupported iron oxide: An FTIR and XPS

sorption on variable-charge soil using the triple-layer model. Journal of Colloid and Interface Science. 2005;**292**(1):171-178. DOI: 10.1016/j.

jcis.2005.05.074

10.1021/jp0751357

s40097-014-0114-1

[28] Ghaffari A, Tehrani MS, Husain SW, Anbia M, Azar PA. Adsorption of chlorophenols from aqueous solution over amino-modified ordered nanoporous silica materials. Journal of Nanostructure in Chemistry. 2014;**4**(3):114. DOI: 10.1007/

*Adsorption Configurations of 2-Chlorophenols on Colloidal Silica DOI: http://dx.doi.org/10.5772/intechopen.88113*

monochlorophenols in aqueous solution at elevated temperatures. Journal of Solution Chemistry. 2003;**32**(1):19-39. DOI: 10.1023/a:1022980614320

*Colloid Science in Pharmaceutical Nanotechnology*

from wastewater. Chemistry of Materials. 2005;**17**(1):212-216. DOI:

[21] Zhang L, Zhang B, Wu T, Sun D, Li Y. Adsorption behavior and mechanism of chlorophenols onto organoclays in aqueous solution. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 2015;**484**:118-129. DOI: 10.1016/j.colsurfa.2015.07.055

[22] Wahab HS, Bredow T, Aliwi SM. A computational study on the adsorption and ring cleavage of para-chlorophenol on anatase TiO2 surface. Surface Science. 2009;**603**(4):664-669. DOI:

[23] Vaishya RC, Gupta SK. Modelling arsenic(III) adsorption from water by sulfate-modified iron oxide-coated sand (SMIOCS). Journal of Chemical

2003;**78**(1):73-80. DOI: 10.1002/jctb.745

[24] Cho GS, Lee D-H, Lim HM, Lee S-H, Kim C, Kim DS. Characterization of surface charge and zeta potential of colloidal silica prepared by various methods. Korean Journal of Chemical Engineering. 2014;**31**(11):2088-2093. DOI: 10.1007/s11814-014-0112-5

[25] Soltani T, Lee B-K. Mechanism of highly efficient adsorption of 2-chlorophenol onto ultrasonic graphene materials: Comparison and equilibrium. Journal of Colloid and Interface Science. 2016;**481**:168-180. DOI: 10.1016/j.jcis.2016.07.049

[26] Shirzad-Siboni M, Jafari S-J,

[27] Uchida M, Okuwaki A. UV-vis spectrophotometric determination of the dissociation constants for

eer.2013.18.4.247

Farrokhi M, Yang JK. Removal of phenol from aqueous solutions by activated red mud: Equilibrium and kinetics studies. Environmental Engineering Research. 2013;**18**(4):247-252. DOI: 10.4491/

10.1016/j.susc.2009.01.001

Technology & Biotechnology.

10.1021/cm048393e

peach juice samples. Journal of Chromatography A. 2014;**1361**:60-66. DOI: 10.1016/j.chroma.2014.08.002

S0021-9797(03)00393-X

10.1071/CH9771417

[15] Farrah H, Pickering W. The sorption of lead and cadmium species by clay minerals. Australian Journal of Chemistry. 1977;**30**(7):1417-1422. DOI:

[16] Feddal I, Ramdani A, Taleb S, Gaigneaux EM, Batis N, Ghaffour

pollutant, by montmorillonite clay. Desalination and Water Treatment. 2014;**52**(13-15):2654-2661. DOI: 10.1080/19443994.2013.865566

[17] Johnson BB. Effect of pH,

es00071a014

tb02096.x

temperature, and concentration on the adsorption of cadmium on goethite. Environmental Science & Technology. 1990;**24**(1):112-118. DOI: 10.1021/

[18] Jarvis SC, Jones LHP. The contents and sorption of cadmium in some agricultural soils of England and Wales. Journal of Soil Science. 1980;**31**(3): 469-479. DOI: 10.1111/j.1365-2389.1980.

[19] Weerasooriya R, Wickramarathne HUS, Dharmagunawardhane HA. Surface complexation modeling of fluoride adsorption onto kaolinite. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 1998;**144**(1):267-273. DOI: 10.1016/S0927-7757(98)00646-3

[20] Sayari A, Hamoudi S, Yang Y. Applications of pore-expanded mesoporous silica. 1. Removal of heavy metal cations and organic pollutants

N. Adsorption capacity of methylene blue, an organic

[14] Zhang X, Bai R. Mechanisms and kinetics of humic acid adsorption onto chitosan-coated granules. Journal of Colloid and Interface Science. 2003;**264**(1):30-38. DOI: 10.1016/

**42**

[28] Ghaffari A, Tehrani MS, Husain SW, Anbia M, Azar PA. Adsorption of chlorophenols from aqueous solution over amino-modified ordered nanoporous silica materials. Journal of Nanostructure in Chemistry. 2014;**4**(3):114. DOI: 10.1007/ s40097-014-0114-1

[29] Hayes KF, Papelis C, Leckie JO. Modeling ionic strength effects on anion adsorption at hydrous oxide/solution interfaces. Journal of Colloid and Interface Science. 1988;**125**(2):717-726. DOI: 10.1016/0021-9797(88)90039-2

[30] Cea M, Seaman JC, Jara AA, Mora ML, Diez MC. Describing chlorophenol sorption on variable-charge soil using the triple-layer model. Journal of Colloid and Interface Science. 2005;**292**(1):171-178. DOI: 10.1016/j. jcis.2005.05.074

[31] Li Y, Li X, Dong C, Li Y, Jin P, Qi J. Selective recognition and removal of chlorophenols from aqueous solution using molecularly imprinted polymer prepared by reversible addition-fragmentation chain transfer polymerization. Biosensors and Bioelectronics. 2009;**25**(2):306-312. DOI: 10.1016/j.bios.2009.07.001

[32] Song D, Li J, Cai Q. In situ diffuse reflectance FTIR study of CO adsorbed on a cobalt catalyst supported by silica with different pore sizes. The Journal of Physical Chemistry C. 2007;**111**(51):18970-18979. DOI: 10.1021/jp0751357

[33] Mosallanejad S, Dlugogorski BZ, Kennedy EM, Stockenhuber M. Adsorption of 2-chlorophenol on the surface of silica- and aluminasupported iron oxide: An FTIR and XPS study. ChemCatChem. 2017;**9**(3):481- 491. DOI: 10.1002/cctc.201601069

[34] Alderman SL, Dellinger B. FTIR investigation of 2-chlorophenol chemisorption on a silica surface from 200 to 500°C. The Journal of Physical Chemistry A. 2005;**109**(34):7725-7731. DOI: 10.1021/jp051071t

[35] Bardakçı B. Monitoring of monochlorophenols adsorbed on metal (Cu and Zn) supported pumice by infrared spectroscopy. Environmental Monitoring and Assessment. 2009;**148**(1):353-357. DOI: 10.1007/ s10661-008-0165-1

[36] Lochab B, Shukla S, Varma IK. Naturally occurring phenolic sources: Monomers and polymers. RSC Advances. 2014;**4**(42):21712-21752. DOI: 10.1039/c4ra00181h

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Section 2

Colloid Science and

Biotechnology

Section 2
