**6. Characterization**

### **6.1 Growth curve analysis**

Growth curve analysis (GCA) allowed assessing the effect of the ROS generated from the TiO2 upon UV irradiation. As mentioned, we tested two bacteria: *E. coli* and *S. aureus*. We removed the bacterial media from the hood (protocol described previously) and mixed them with the films impregnated with TiO2 in laboratory plastic tubes as shown in **Table 1**.

A spectrophotometer allowed measuring the optical density (OD) of each master solution for each bacterium so that one could extract a fixed amount of volume (aliquot) from the solution for each bacterium. This aliquot was then added and mixed to each laboratory plastic tube with the bacteria medium and biocomposite film, as mentioned above. To know exactly how much volume was needed, Eq. [7] was used. Eq. [7] related the volume needed (*V*2) of aliquot to add to each plastic tube. C1, C2, and V1 are the concentration of the plastic tube, the concentration in the master solution, and volume of medium already in the plastic tube (20 mL), respectively. The concentration was obtained from the OD measurement.

$$V\_2 = \frac{C\_1 V\_1}{C\_2} \tag{7}$$

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**Figure 5.**

*Biodegradable Chitosan Matrix Composite Reinforced with Titanium Dioxide for Biocidal…*

**Number of laboratory tubes Group** *S. aureus E. coli* **Control TiO2 UV** Day 1 3 3 3 Yes Yes

Day 2 3 3 3 No No

3 3 3 No Yes

3 3 3 Yes No

films with bacteria medium, and the group with *S. aureus* and films with bacteria

During the wait time, i.e., between measurements, the test tubes remained inside the shaker under optimal conditions for bacterial growth. It is important to understand that we completed this entire process twice. As UV light irradiated the samples, we covered the shaker with a black box to block any other light source. **Figures 5** and **6** show how the films without any UV irradiation affected the

**Figures 5** and **6** prove the negligible antibacterial capacity of the films without photoactivation (no UV light). As we can observe in both **Figures 5** and **6**, the samples with bacteria grow normally (if we compared the sample with only bacteria with the samples of bacteria and films), while the samples without bacteria stay constant (0.0 absorbance) until close to the end of the experiment. The samples are either grouped on the top (samples with bacteria) or in the bottom (samples without bacteria). On the other hand, **Figures 7** and **8** (obtained for *S. aureus* and *E. coli*, respectively) have shown that the effect of photoactivated films becomes apparent. The growth rate reduction is attributed to the effects of the ROS liberated

**Figures 7** and **8** display a difference in the bacteria growth on the films photoactivated by UV. Further, **Figures 9** and **10** (obtained for *S. aureus* and *E. coli*, respectively) evince the difference in growth percent of the bacteria exposed to the

*S. aureus exposed for 8 h to the chitosan films impregnated with TiO2, without UV irradiation. The upper* 

*curves indicate the presence of bacteria, while the bottom ones indicate lower bacteria content.*

utes three times (20, 40, and 60 minutes) of the mix preparation, then after 40 minutes three times (100, 140, and 180 minutes), and, finally, after an hour five

*The number of laboratory plastic tubes used and how the groups were organized.*

After the three groups were ready, we measured the OD after the first 20 min-

*DOI: http://dx.doi.org/10.5772/intechopen.84397*

times (240, 300, 360, 420, and 480 minutes).

from TiO2 when exposed to energy from the UV light.

medium.

**Table 1.**

bacteria growth.

**Table 1** presents the three groups formed, i.e., the control group with only the composite films and the medium without bacteria, the group with *E. coli* and *Biodegradable Chitosan Matrix Composite Reinforced with Titanium Dioxide for Biocidal… DOI: http://dx.doi.org/10.5772/intechopen.84397*


**Table 1.**

*Renewable and Sustainable Composites*

**5.3 Bacteria medium preparation for growth curve analysis**

enough samples to be tested with and without UV.

*V*<sup>2</sup> = \_\_\_\_

**6. Characterization**

**Figure 4.**

**6.1 Growth curve analysis**

plastic tubes as shown in **Table 1**.

In this protocol, we prepared the bacterial medium of Luria broth (LB) nearly 24 h before each experiment. All laboratory glassware was autoclaved for 15 minutes before use. One liter of water was mixed with 10 g of LB assisted by a magnetic agitator. After obtaining a visually homogenous mixture, we divided it in three groups of laboratory plastic tubes, namely, control, *E. coli*, and *S. aureus*, and autoclaved a second time for 15 minutes. Each bacteria medium was left overnight inside a fume hood under UV light. Two master solutions were separated from the group, incubated with the bacteria, and left inside a shaker at 200 rpm and 37.0°C for almost 6 h. We followed this entire procedure twice per experiment to produce

*Films as extracted from the oven. (A) 0.0% TiO2, (B) 0.5% TiO2, (C) 1.0% TiO2, and (D) 1.5% TiO2.*

Growth curve analysis (GCA) allowed assessing the effect of the ROS generated from the TiO2 upon UV irradiation. As mentioned, we tested two bacteria: *E. coli* and *S. aureus*. We removed the bacterial media from the hood (protocol described previously) and mixed them with the films impregnated with TiO2 in laboratory

A spectrophotometer allowed measuring the optical density (OD) of each master solution for each bacterium so that one could extract a fixed amount of volume (aliquot) from the solution for each bacterium. This aliquot was then added and mixed to each laboratory plastic tube with the bacteria medium and biocomposite film, as mentioned above. To know exactly how much volume was needed, Eq. [7] was used. Eq. [7] related the volume needed (*V*2) of aliquot to add to each plastic tube. C1, C2, and V1 are the concentration of the plastic tube, the concentration in the master solution, and volume of medium already in the plastic tube (20 mL), respectively. The concentration was obtained from the OD

> *C*1*V*<sup>1</sup> *C*2

**Table 1** presents the three groups formed, i.e., the control group with only the composite films and the medium without bacteria, the group with *E. coli* and

(7)

**80**

measurement.

*The number of laboratory plastic tubes used and how the groups were organized.*

films with bacteria medium, and the group with *S. aureus* and films with bacteria medium.

After the three groups were ready, we measured the OD after the first 20 minutes three times (20, 40, and 60 minutes) of the mix preparation, then after 40 minutes three times (100, 140, and 180 minutes), and, finally, after an hour five times (240, 300, 360, 420, and 480 minutes).

During the wait time, i.e., between measurements, the test tubes remained inside the shaker under optimal conditions for bacterial growth. It is important to understand that we completed this entire process twice. As UV light irradiated the samples, we covered the shaker with a black box to block any other light source. **Figures 5** and **6** show how the films without any UV irradiation affected the bacteria growth.

**Figures 5** and **6** prove the negligible antibacterial capacity of the films without photoactivation (no UV light). As we can observe in both **Figures 5** and **6**, the samples with bacteria grow normally (if we compared the sample with only bacteria with the samples of bacteria and films), while the samples without bacteria stay constant (0.0 absorbance) until close to the end of the experiment. The samples are either grouped on the top (samples with bacteria) or in the bottom (samples without bacteria). On the other hand, **Figures 7** and **8** (obtained for *S. aureus* and *E. coli*, respectively) have shown that the effect of photoactivated films becomes apparent. The growth rate reduction is attributed to the effects of the ROS liberated from TiO2 when exposed to energy from the UV light.

**Figures 7** and **8** display a difference in the bacteria growth on the films photoactivated by UV. Further, **Figures 9** and **10** (obtained for *S. aureus* and *E. coli*, respectively) evince the difference in growth percent of the bacteria exposed to the

### **Figure 5.**

*S. aureus exposed for 8 h to the chitosan films impregnated with TiO2, without UV irradiation. The upper curves indicate the presence of bacteria, while the bottom ones indicate lower bacteria content.*

### **Figure 6.**

*E. coli exposed for 8 h to the chitosan films impregnated with TiO2, without UV irradiation. The upper curves indicate the presence of bacteria, while the bottom ones indicate lower bacteria content.*

**Figure 7.** *S. aureus exposed for 8 h to the chitosan films impregnated with TiO2, with UV irradiation.*

**Figure 8.** *E. coli exposed for 8 h to the chitosan films impregnated with TiO2, with UV irradiation.*

films after the growth rate stabilized at the end of the experiment. As observed in these two figures, the celling line corresponds to the normal growth of the bacteria. The bars represent the growth rate of each bacterium exposed to the different concentrations of TiO2 in the films. **Figures 11** and **12** show the same bacteria groups exposed to the same level of TiO2 but this time with UV light.

**83**

with UV light.

**Figure 10.**

**Figure 9.**

**6.2 Inhibition ring analysis**

*Biodegradable Chitosan Matrix Composite Reinforced with Titanium Dioxide for Biocidal…*

*Growth percent of S. aureus exposed for 8 h to the biocomposite films made of chitosan and TiO2***.**

As observed in **Figures 9** and **10**, the celling line is the normal growth of the bacteria. The bars are the bacteria exposed to the different concentrations of TiO2 in the films. **Figures 11** and **12** (obtained for *S. aureus* and *E. coli*, respectively) show the same bacteria groups exposed to the same concentration of TiO2 but this time

*Growth percent of E. coli exposed for 8 h to the biocomposite films made of chitosan and TiO2.*

**Figures 11** and **12** demonstrate how the exposure of the films to the UV light did affect the bacteria growth. One can say that the UV light alone is detrimental to the bacteria but the experiments with only UV exposure did not affect the growth rate significantly.

This analysis, also known as the Kirby-Bauer (KB) method, helps determine the susceptibility to solutions or drugs of isolated microorganisms, i.e., in our case *E. coli* and *S. aureus*. We cut the films as circular pieces using a paper perforator so

*DOI: http://dx.doi.org/10.5772/intechopen.84397*

*Biodegradable Chitosan Matrix Composite Reinforced with Titanium Dioxide for Biocidal… DOI: http://dx.doi.org/10.5772/intechopen.84397*

### **Figure 9.**

*Renewable and Sustainable Composites*

**82**

**Figure 8.**

**Figure 7.**

**Figure 6.**

films after the growth rate stabilized at the end of the experiment. As observed in these two figures, the celling line corresponds to the normal growth of the bacteria. The bars represent the growth rate of each bacterium exposed to the different concentrations of TiO2 in the films. **Figures 11** and **12** show the same bacteria groups

exposed to the same level of TiO2 but this time with UV light.

*E. coli exposed for 8 h to the chitosan films impregnated with TiO2, with UV irradiation.*

*S. aureus exposed for 8 h to the chitosan films impregnated with TiO2, with UV irradiation.*

*E. coli exposed for 8 h to the chitosan films impregnated with TiO2, without UV irradiation. The upper curves* 

*indicate the presence of bacteria, while the bottom ones indicate lower bacteria content.*

*Growth percent of S. aureus exposed for 8 h to the biocomposite films made of chitosan and TiO2***.**

**Figure 10.** *Growth percent of E. coli exposed for 8 h to the biocomposite films made of chitosan and TiO2.*

As observed in **Figures 9** and **10**, the celling line is the normal growth of the bacteria. The bars are the bacteria exposed to the different concentrations of TiO2 in the films. **Figures 11** and **12** (obtained for *S. aureus* and *E. coli*, respectively) show the same bacteria groups exposed to the same concentration of TiO2 but this time with UV light.

**Figures 11** and **12** demonstrate how the exposure of the films to the UV light did affect the bacteria growth. One can say that the UV light alone is detrimental to the bacteria but the experiments with only UV exposure did not affect the growth rate significantly.

### **6.2 Inhibition ring analysis**

This analysis, also known as the Kirby-Bauer (KB) method, helps determine the susceptibility to solutions or drugs of isolated microorganisms, i.e., in our case *E. coli* and *S. aureus*. We cut the films as circular pieces using a paper perforator so

**Figure 11.** *Growth percentage of S. aureus exposed for 8 h to the biocomposite films made of chitosan and TiO2 with UV light.*

**Figure 12.** *Growth percentage of E. coli exposed for 8 h to the biocomposite films made of chitosan and TiO2 with UV light.*

that all pieces had the same diameter. These were then exposed to UV irradiation for different times. The best results were obtained on films exposed to UV light for 168 h, as shown in **Figures 13** and **14**. When the UV exposure was over, we placed the films over the bacteria in the Petri dishes. Afterward, the bacteria would grow forming a ring along the chitosan piece with NPs. We measured the area of this ring as a measure of the biocidal potential of the biocomposite. In other words, a larger ring area represented better antibacterial properties of the material.

**Figure 13** shows four groups of *S. aureus*. Each group was exposed to a different film with different TiO2 concentrations. The horizontal axis corresponds to the time elapsed after the films were placed over the bacteria. Naturally, at 0.00 h there was no inhibition ring yet since the films had just been placed on the bacteria.

Similar to **Figure 13**, **Figure 14** has the bacteria *E. coli* exposed to different concentrations of TiO2. The very first point after the films were placed was without inhibition rings yet. Here the optimal TiO2 concentration was 1.0% and not 1.5%, which was to be expected due to the double membrane that the *E. coli* possesses.

**85**

*Biodegradable Chitosan Matrix Composite Reinforced with Titanium Dioxide for Biocidal…*

*Area of inhibition ring for S. aureus after films are exposed for 168 h to UV light. Each bar was a different data* 

*DOI: http://dx.doi.org/10.5772/intechopen.84397*

*point of the same plate taken continuously every 24 h.*

**6.3 Fourier-transform infrared (FTIR)**

*point of the same plate taken continuously every 24 h.*

time under UV light.

**Figure 13.**

**Figure 14.**

and after such UV exposure.

respectively. The band at 1618 cm<sup>−</sup><sup>1</sup>

The Fourier-transform infrared (FTIR) spectroscopy helps identify functional groups in a molecule. In our case, we used it to identify the chemical bonds present and how they degraded after UV exposure. As it is well-known, UV irradiation degrades the covalent bonds in polymers, rendering them brittle after a prolonged

*Area of inhibition ring of E. coli after films are exposed for 168 h to UV light. Each bar was a different data* 

In that context, FTIR spectroscopy, as a chemical analytical technique, helps measure the infrared intensity as a function of the wavelength (or wave number) of light. Based upon said wave number, infrared light can be categorized as far infrared, mid infrared, and near infrared for use in polymer science, organic synthesis, petrochemical engineering, food analysis, and even pharmaceutical industries [41, 42]. **Figures 15**–**18** show the results from four films after the UV exposure. Even more, by using the transmittance percent, we can detect the difference among films before

stretching vibration of O▬H groups, C▬H group, C▬N groups, and C▬O▬C groups,

was attributed to the bending vibration of N-H.

were assigned to the

The characteristic bands of 3400, 3000, 1080, and 1030 cm<sup>−</sup><sup>1</sup>

*Biodegradable Chitosan Matrix Composite Reinforced with Titanium Dioxide for Biocidal… DOI: http://dx.doi.org/10.5772/intechopen.84397*

### **Figure 13.**

*Renewable and Sustainable Composites*

**Figure 11.**

**Figure 12.**

that all pieces had the same diameter. These were then exposed to UV irradiation for different times. The best results were obtained on films exposed to UV light for 168 h, as shown in **Figures 13** and **14**. When the UV exposure was over, we placed the films over the bacteria in the Petri dishes. Afterward, the bacteria would grow forming a ring along the chitosan piece with NPs. We measured the area of this ring as a measure of the biocidal potential of the biocomposite. In other words, a larger

*Growth percentage of E. coli exposed for 8 h to the biocomposite films made of chitosan and TiO2 with UV light.*

*Growth percentage of S. aureus exposed for 8 h to the biocomposite films made of chitosan and TiO2 with UV light.*

**Figure 13** shows four groups of *S. aureus*. Each group was exposed to a different film with different TiO2 concentrations. The horizontal axis corresponds to the time elapsed after the films were placed over the bacteria. Naturally, at 0.00 h there was

ring area represented better antibacterial properties of the material.

no inhibition ring yet since the films had just been placed on the bacteria.

Similar to **Figure 13**, **Figure 14** has the bacteria *E. coli* exposed to different concentrations of TiO2. The very first point after the films were placed was without inhibition rings yet. Here the optimal TiO2 concentration was 1.0% and not 1.5%, which was to be expected due to the double membrane that the *E. coli* possesses.

**84**

*Area of inhibition ring for S. aureus after films are exposed for 168 h to UV light. Each bar was a different data point of the same plate taken continuously every 24 h.*

#### **Figure 14.**

*Area of inhibition ring of E. coli after films are exposed for 168 h to UV light. Each bar was a different data point of the same plate taken continuously every 24 h.*

### **6.3 Fourier-transform infrared (FTIR)**

The Fourier-transform infrared (FTIR) spectroscopy helps identify functional groups in a molecule. In our case, we used it to identify the chemical bonds present and how they degraded after UV exposure. As it is well-known, UV irradiation degrades the covalent bonds in polymers, rendering them brittle after a prolonged time under UV light.

In that context, FTIR spectroscopy, as a chemical analytical technique, helps measure the infrared intensity as a function of the wavelength (or wave number) of light. Based upon said wave number, infrared light can be categorized as far infrared, mid infrared, and near infrared for use in polymer science, organic synthesis, petrochemical engineering, food analysis, and even pharmaceutical industries [41, 42]. **Figures 15**–**18** show the results from four films after the UV exposure. Even more, by using the transmittance percent, we can detect the difference among films before and after such UV exposure.

The characteristic bands of 3400, 3000, 1080, and 1030 cm<sup>−</sup><sup>1</sup> were assigned to the stretching vibration of O▬H groups, C▬H group, C▬N groups, and C▬O▬C groups, respectively. The band at 1618 cm<sup>−</sup><sup>1</sup> was attributed to the bending vibration of N-H.

A transmittance increment becomes evident after the UV light exposure on the films according to our results in **Figures 15–18**. The breakdown of the covalent bonds in the polymer reveals the degradation. Each valley is a different bond that when degraded absorbs less energy.

### **6.4 X-ray diffraction (XRD)**

X-ray diffraction (XRD) is a phase identification tool in crystal materials [43]. In the present study, XRD analysis allowed confirming the crystalline nature of the TiO2 used, identifying it as the anatase polymorph. A comparison between two diffraction patterns is in **Figure 19**. Further, this XRD analysis revealed that during the entire synthesis, process of the films (described in Section 5.2) did not affect the original anatase polymorph of the TiO2. In effect, via **Figure 19**, we can conclude this because each peak (reflected by specific indexed crystallographic planes) aligns

**Figure 15.** *FTIR spectrum of the 0.0% TiO2 film after the UV exposure (blue line) for 24 h and without UV exposure (black line).*

**Figure 16.**

*FTIR spectrum of the 0.5% TiO2 film after the UV exposure (blue line) for 24 h and without any exposure (black line).*

**87**

**Figure 18.**

**Figure 17.**

*(black line).*

*(black line).*

*Biodegradable Chitosan Matrix Composite Reinforced with Titanium Dioxide for Biocidal…*

almost perfectly with the anatase pattern. This is an important finding since any formation of the two other polymorphs or even the amorphous alternative would

*FTIR spectrum of the 1.5% TiO2 film after the UV exposure (blue line) for 24 h and without any exposure* 

*FTIR spectrum of the 1.0% TiO2 film after the UV exposure (blue line) for 24 h and without any exposure* 

Scanning electron microscopy (SEM) helped acquire information about the external morphology (texture) of the films [44]. In this research, SEM confirmed the adequate TiO2 dispersion within the chitosan matrix. **Figure 20** shows the 0.0% and 0.5% films with two (2) different positions and angle for each sample. **Figure 21** reveals analogous information for the films 1.0 and 1.5%. As the amount

have resulted in a loss of the photocatalytic capacity of the dioxide.

**6.5 Scanning electron microscopy (SEM)**

of NPs increased, the uniformity was maintained.

*DOI: http://dx.doi.org/10.5772/intechopen.84397*

*Biodegradable Chitosan Matrix Composite Reinforced with Titanium Dioxide for Biocidal… DOI: http://dx.doi.org/10.5772/intechopen.84397*

### **Figure 17.**

*Renewable and Sustainable Composites*

when degraded absorbs less energy.

**6.4 X-ray diffraction (XRD)**

A transmittance increment becomes evident after the UV light exposure on the films according to our results in **Figures 15–18**. The breakdown of the covalent bonds in the polymer reveals the degradation. Each valley is a different bond that

X-ray diffraction (XRD) is a phase identification tool in crystal materials [43]. In the present study, XRD analysis allowed confirming the crystalline nature of the TiO2 used, identifying it as the anatase polymorph. A comparison between two diffraction patterns is in **Figure 19**. Further, this XRD analysis revealed that during the entire synthesis, process of the films (described in Section 5.2) did not affect the original anatase polymorph of the TiO2. In effect, via **Figure 19**, we can conclude this because each peak (reflected by specific indexed crystallographic planes) aligns

*FTIR spectrum of the 0.0% TiO2 film after the UV exposure (blue line) for 24 h and without UV exposure (black line).*

*FTIR spectrum of the 0.5% TiO2 film after the UV exposure (blue line) for 24 h and without any exposure* 

**86**

**Figure 16.**

*(black line).*

**Figure 15.**

*FTIR spectrum of the 1.0% TiO2 film after the UV exposure (blue line) for 24 h and without any exposure (black line).*

**Figure 18.** *FTIR spectrum of the 1.5% TiO2 film after the UV exposure (blue line) for 24 h and without any exposure (black line).*

almost perfectly with the anatase pattern. This is an important finding since any formation of the two other polymorphs or even the amorphous alternative would have resulted in a loss of the photocatalytic capacity of the dioxide.

### **6.5 Scanning electron microscopy (SEM)**

Scanning electron microscopy (SEM) helped acquire information about the external morphology (texture) of the films [44]. In this research, SEM confirmed the adequate TiO2 dispersion within the chitosan matrix. **Figure 20** shows the 0.0% and 0.5% films with two (2) different positions and angle for each sample. **Figure 21** reveals analogous information for the films 1.0 and 1.5%. As the amount of NPs increased, the uniformity was maintained.

### **Figure 19.**

*XRD analysis diffraction of the TiO2 used in the research, compared to pattern of anatase.*

**Figure 20.** *SEM images of the films containing 0.0% TiO2 (A, B) and 0.5% TiO2 (C, D).*

For each film, multiple shots were taken at different angles and positions within the films. **Figures 20** and **21** present the most typical configurations of the particle dispersion. **Figure 20** A and B shows the surface of the chitosan without NPs. SEM analysis in overall

**89**

**8. Conclusions**

*Biodegradable Chitosan Matrix Composite Reinforced with Titanium Dioxide for Biocidal…*

showed a uniform distribution of TiO2 nanoparticle clots over the chitosan film as no large aggregate was observed. No phase separation was evident, as the TiO2 content increased.

As a whole, the results in Figures 5 through 12 prove clearly that the biocomposite film made of chitosan and TiO2 NPs can be photoactivated. Once the films containing NPs have produced ROS, they are capable of reducing significantly the amount and growth rate of bacteria. Two different tests (viz., the growth curve analysis and the Kirby-Bauer technique) present incontrovertible evidence that when the bacteria are exposed to the photoactivated biocomposites, their growth pattern is affected, and the end amount is lower. We already mentioned that the reviewed literature proved that the main mechanism affecting the bacteria growth is the production of ROS rendered by the TiO2 upon UV light irradiation. However, in order for these ROS to be effective (in sufficient concentration), the correct polymorph of TiO2 is needed, i.e., anatase. For this reason, we selected this dioxide NPs, seeking to obtain more ROS, as mentioned in Section 4 of this chapter. Nonetheless, it is well-known that different processing conditions (involving temperature) of titanium dioxide can lead to a phase change. Thanks to the XRD characterization, we were able to confirm that the crystal structure used throughout this research was anatase and that the synthesis process of the biocomposite films did not change its crystal structure. During the said process, the mixing methods used to disperse uniformly the TiO2 NPs in the chitosan could have caused clots and agglomeration of the particles. This was the only reason to use a SEM (secondary imaging mode) to acquire the images shown in Section 6.5. The technique allowed scrutinizing the entire film exposed surface from different angles. This extensive survey did not evince any large clots or even lumps of NPs on the surface of the films. These images also proved that the attachment of the NPs onto the chitosan films was efficacious. In effect, as the TiO2 content increased more, film surface was uniformly covered by

To reveal the interaction between TiO2 and chitosan before and after UV irradiation, as already presented in Section 6.3, we acquired a set of FTIR spectra. Due to the addition of oxygen atoms from the TiO2 NPs, one can observe a more intense peak from the O-H bond in **Figures 16–18**. Along that line, as the UV light photoactivated the TiO2, the spectral data revealed a smaller intensity from this bond (O▬H) after the UV irradiation. Finally, the bond nigh 3000 cm<sup>−</sup><sup>1</sup>

indicates a degradation of the chitosan polymer as this peak decreases. This could result in a more brittle substrate to hold the nanoparticles, which should be taken

In closing, even with the rise of superbugs and the decline in effectiveness of antibiotics, innovated materials like nanoparticles show a promising future as the next generation of antimicrobial. In this context, our chitosan/TiO2 biocomposite films can represent an economic option when compared to other materials for similar applications, such as activated carbon, capable of reducing the bacteria present in water. The synthesis process is reproducible and very economical, creating a

This chapter presents an appealing alternative of a novel antibacterial material. The use of chitosan was due to its versatility, its abundance in nature, and excellent

into consideration in upcoming applications of the composite.

(C▬H)

*DOI: http://dx.doi.org/10.5772/intechopen.84397*

the NPs, and no detachment occurred.

technology with ample potential application.

**7. Discussion**

showed a uniform distribution of TiO2 nanoparticle clots over the chitosan film as no large aggregate was observed. No phase separation was evident, as the TiO2 content increased.
