**4. Nanomaterial and their application from biological analysis**

#### **4.1 Nanomaterial-driven faster and more accurate cell analysis**

Early detection and diagnosis can play a pivotal role in the battle against many diseases. Scientists harness the unique attributes of nanomaterials to generate novel molecular contrast agents for *in vivo* imaging, sensing, measuring response to therapy, and liquid biopsy to study disease initiation, progression, and therapeutic response. Nanotechnology has a spacious range of accurate cell analyses. As described above, nanotechnology facilitates the development of desired formulations for individual cell analysis and their specific treatment applications, developing only one of its kind of applications for cell sensing/sensors, imaging, delivery, and diagnosis [39]. Since the importance of accurate cell analysis for nanoparticles is the latest approach, there is a big void for more discoveries and optimizations in various bio-applications.

#### **4.2 Nanomaterial and** *in vivo* **imaging**

The main lacunae in cancer treatment are a late diagnosis. The resolution of current imaging methods is low and can detect cancers at the late/ advanced stage or metastasized. A tissue biopsy can only help physicians to ascertain the tumor type and characteristics. Detection becomes even more challenging when metastatic modules and micrometastasis need to be identified. *In vivo* imaging enables us to non or minimally-invasively delve deep into the patient's tissue and is becoming increasingly popular for basic research and clinical applications. *In vivo,* molecular imaging focuses on obtaining spatiotemporal information about molecules of medical interest or biomarkers within a living body in real-time. Molecular *in vivo* imaging relies on contrast agents or medium that increases the contrast of physiological structure and enhances the sensitivity of detection. Different contrast agents are used for different *in vivo* imaging techniques including, radiocontrast, magnetic resonance imaging (MRI) contrast, ultrasound contrast, and optical contrast agents [40]. Precision diagnostics is dependent on high-resolution and high-contrast images. Nanomaterials are critical players in the generation of advanced contrast agents or media. Imageable nanoparticles can be classified based on their applications in nuclear, magnetic, optical, and acoustic imaging modalities. Moreover, NP-based contrast agents may be designed to integrate multiple detection modules and target specific cells. The advantages of nanoparticle-based contrast agents include enhanced specificity, increased photo and chemical stability, longer circulation time, engineered clearance pathways, and multimodal applications. The main *in vivo* imaging modalities include MRI, computed tomography (CT), positron emission tomography (PET), single-photon emission computed tomography (SPECT), ultrasonography (US), near-infrared fluorescence (NIRF), and two-photon intravital microscopy [41–43].

#### **4.3 Nanoparticles as bio-sensors**

By virtue of their unique properties, NPs make them ideal for their use for nano bio-sensing applications with enhanced sensitivity. Nanoparticles are widely used for detecting cells and pathogens, separating pathogens, recognize different biological substances, and detecting molecular and cellular functions [41, 42]. Accurate and professional separation of desired cells from the composite of various cell mixtures is essential for numerous biological applications. Nanoparticles have been investigated as a promising and very sensitive tool for the specific identification of cells. Identification and incarceration of metastatic cancer cells in the circulation can help understand and a strong analytical biomarker for various metastatic cancers, which can change the patient's prognosis. Nanoparticle-based methods are more frequently used for the identification and capture of metastatic circulating cancer cells. In this technique, magnetic nanoparticles were used to specifically track and separate the cells by using a

### *Nanotechnology Application and Intellectual Property Right Prospects of Mammalian Cell... DOI: http://dx.doi.org/10.5772/intechopen.99146*

ligand-receptor-based mechanism [42]. These techniques can also be used for the white blood cells with an anti-CD45-APC as a nanoparticle targeting ligand [44].

Additionally, various nanoparticle-based technologies have been investigated as a sensor for the identification and selection of various pathogens. The most frequently used method for finding bacteria is magnetic biosensors that involve immunological mechanisms using magnetic nanoparticles functionalized with antibodies against surface antigens. Many researchers have been utilizing small molecule tethered nanoparticles to analyze the bacteria successfully. Magnetic glyco-nanoparticles mediated particles could detect bacteria within 5 minutes, including subtraction from the sample by the bacterial interaction with carbohydrates on mammalian cell surfaces [41].

#### **4.4 Nanoparticles as imaging agents**

Nanoparticles have been investigated as imaging agents due to their exceptional physicochemical attributes for various biomedical applications such as cancers and cardiovascular diseases. Fluorescent labels can be easily conjugated to the surfaces of the nanoparticles by various chemical methods to design a wide range of imaging agents for dynamic *in vitro* and *in vivo* cellular imaging [45, 46]. Due to their passive and active targeting nature, nanoparticles can easily identify their specific biomarkers and accumulate at high concentrations in the targeted tissue. The high capability for nanoparticle modification and retention properties in the specific tissue region empowers their utilization as imaging amplifiers. Quantum dots are the most promising fluorescent labels for cellular imaging among all nanoparticles due to their inherent near infra region light emitting nature, reducing autofluorescence [47].

RGD peptide conjugated self-emitting quantum dots can be used for specific integrins highly expressed in tumors. The targeted nanoparticle has been examined for complex imaging competence, like imaging various molecular targets using different spectral emissions specific nanoparticles. Recently, nanotechnology has been used for imaging metastatic tumor cells in circulation, tumor cells, and their vasculature, stem cells, and lymph nodes [48]. Che et al. designed shortwave infrared window (SWIR) responsive QDs for bone-specific real-time *in vivo* and *ex vivo* imaging and could visualize the significant bone structures Balb/C nude and Balb/C mouse [49]. The use of specific nanoparticles can help accurately decipher and image the gram-negative and gram-positive bacteria. Due to their fluorescence characteristics and specific bacterial cell wall interactions, they can be used in a wash-free fashion in bacterial imaging, which is significant for health care, food processing, and medical hygiene.

#### **4.5 Application of nanoparticles in theranostics**

Theranostic NMs are designed by the consolidation of diagnostic and therapeutic abilities in one biodegradable nanoparticle [50]. Novel theranostic materials should have the following properties; i) highly compatible with biological entities, ii) proficiently and precisely accumulate in desired morbid tissue, iii) describe the biochemical and morphological attributes of maladies, iv) exhibit minimal toxicological effects, v) and deliver a sufficient amount of therapeutic agent. Several techniques have been used to functionalize the surface of nanoparticles for theranostics use. Surface functionalization may include imaging agents, drugs, therapeutic cargo, nucleic acid, and contrast agents by either chemical functionalization or by biofunctionalization. Chemical functionalization depends on chemical cross-linking, while biofunctionalization of nanoparticles relies on bioinspired ligands obtained from

natural phytochemicals). The use of nanotechnology offers a promising alternative for the diagnosis of various cancers. Various investigations convey that nanoparticles could be engineered for advanced diagnostic agents to detect cancers [51]. Double drug encapsulated liposomes can be functionalized to enhance theranostic efficacy [51, 52]. Multifunctional Metal nanoparticles can serve as a unique platform for cancer theranostics. The range of use of metal nanoparticles includes MRI imaging, biological catalysis, magnetic hyperthermia, magnetic drug delivery, photo-responsive drug delivery, and cell separation. Metal nanoparticles, including, Polymer-NP constructs containing Gd3+ complexes, Fe3 + − terpyridine complexes, and polymeric shell-based contrast agents, are widely studied for their theranostic use as MRI contrast. Magnetic particle imaging (MPI), a novel imaging technique, is based on the analysis of iron oxide NPs in response to a magnetic field.

Cheng et al. used GE11, a novel peptide with EGFR binding affinity and complexed with doxorubicin-loaded liposomes, and observed higher liposomal uptake and accumulation than, unconjugated liposomes using NIRF [53]. In another study Song et al. designed a multifunctional targeting liposome for targeting lung cancer. Octreotide (OCT), a synthetic 8-peptide analog of somatostatin, was used to surface coat the liposome for enhanced binding with the somatostatin receptors overexpressed in a subset of tumors. Double anti-cancer drug (Honokiol and epirubicin) co-encapsulated liposomes showed enhanced OCT- somatostatin receptor binding and *in vivo* response [54]. Cittadino et al. designed a theranostic long-circulating liposome with co-loaded prednisolone phosphate and an amphiphilic paramagnetic gadolinium contrast agent [Gd-DOTAMA(C18)(2)] for MRI monitoring of melanoma. The theranostically engineered liposomes showed long-term MRI-based detection without a loss in drug action [51]. The theranostic nanoparticle could assist in the patient's pre-selection, a prediction for responding to nanomedicine therapy. Moreover, nanomedicine-treated patients could be monitored throughout treatment duration while using nanomedicine formulations [39].
