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Bio-nanomaterials: An Introduction

Abhinoy Kishore, Chaitanayajit Singh, and Gurpreet Kaur*

Department of Biotechnology, Chandigarh College of Technology, Chandigarh Group of Colleges (CGC), Landran, Mohali, Punjab

1.1 Introduction

A bio-nanomaterial encompasses a diverse array of biological molecules and components, such as proteins, antibodies, enzymes, nucleic acids, lipids, polysaccharides, oligosaccharides, viruses, and secondary metabolites, organized at the molecular level to form materials with unique properties and functions [1, 2]. Nanotechnology, a multidisciplinary domain focused on materials at the nanometer scale (1-100 nm), has experienced significant advancements in recent years [3]. This field has diverse applications that extend across a wide spectrum of scientific fields, demonstrating its extensive impact and significance. The term "nanotechnology" stems from the Greek word "nano," denoting one-billionth of a meter, coined by Norio Taniguchi in 1974. This field has significantly advanced medicine by introducing nanosized particles and materials known for their exceptional biocompatibility and minimal toxicity, offering promising avenues for medical innovation and treatment. Bio-nanomaterials are the term assigned to nanosized materials, either composed of or produced through biological means. Nanoparticles, due to their minute size, exhibit extraordinary attributes across various domains including structure, chemistry, physics, optics, heat conductivity, mechanical strength, and electrical conductivity. Their distinctive characteristics position them as versatile tools in the biomedical sector, playing crucial roles in tasks such as advancing tissue engineering, regenerative medicine techniques, drug and gene delivery systems, cancer treatment modalities, and neurodegenerative disease therapies, thereby offering innovative solutions for addressing complex medical challenges [4]. For instance, drug delivery systems are designed to release drugs on target; gene therapy uses vectors that specifically enter targeted cells; cancer treatment employs nanoparticles (NPs) that selectively destroy tumor cells selectively; neurodegenerative diseases are addressed via therapeutic strategies that target specific pathological accumulations andinflammation is managed by therapeutic agents that regulate host immune responses among other possible causes of illnesses [5]. Furthermore, various bio-nanomaterials are utilized as diagnostic tools for identifying various biomarkers or as imaging agents for medical examinations.

Many biodegradable polymers and naturally sourced nanomaterials have been widely employed across biomedical, pharmaceutical, industrial, packaging, and agricultural sectors for the development of bio-nanomaterials. Manipulating materials at the nanoscale now enables fundamental interactions with biological systems, paving the way for customized medication delivery. This breakthrough opens avenues for precise and efficient illness treatment while minimizing adverse effects. Furthermore, bio-nanomaterials are essential in the creation of biosensors and imaging agents, which transform diagnostic methods and make it possible to identify various medical disorders early [6]. Hence, a wide array of biodegradable polymers and naturally derived nanomaterials have found extensive applications across diverse sectors, including biomedical, pharmaceuticals, industrial packaging, and agriculture (Figure 1.1). The utilization of bio-nanomaterials can be traced back to ancient Indian literature, particularly in Ayurveda, a traditional system of medicine practiced in the Indian subcontinent since the 7th century. Ayurvedic treatments often incorporate metal ash, known as Bhasma, to address various diseases [7]. Bhasma comprises metallic or mineral preparations that are treated with herbal juices or decoctions and subjected to specific heating processes, as outlined in the puta system of Ayurveda. Widely recommended across India, Bhasma, a form of bio-nanomaterial, is administered either alone or in combination with medicinal plant extracts or powders, depending on the specific therapeutic needs of the patient [8]. Bio-nanomaterials exhibit diverse applications in environmental remediation, offering significant potential to address various environmental challenges. Both natural and artificial bio-nanomaterials possess unique attributes that can be harnessed to develop efficient and durable remediation methods. These materials hold promise in reducing pollution, restoring ecosystems, and promoting sustainable environmental practices.

Figure 1.1 Applications of bio-nanomaterials. The figure illustrates the diverse range of applications of bio-nanomaterials across various fields, highlighting the versatility and potential impact of bio-nanomaterials, driving innovation and addressing pressing societal needs across diverse domains.

The chapter involves the types of bio-nanomaterials, the various kinds of bio-nanomaterial conjugates, and the application of bio-nanomaterials in various fields ranging from health care and sustainable environmental technologies.

1.2 Types of Bio-nanomaterials

Bio-nanomaterials could be the derivatives of macro biomolecules (biological NPs) or they could be organic or inorganic compounds synthesized via the mediation of biological materials (derived bio-nanomaterials) (Table 1.1).

1.2.1 Classification of Biological Nanoparticles

Biological NPs are classified into four major categories derived from biomolecules or synthesized from organic building blocks, i.e. proteins, nucleic acids, lipids, and polysaccharides.

1.2.1.1 Proteins

Proteins are polymers of amino acids and can be the predecessor for the production of NPs, specifically oligopeptides composed of 8-20 amino acids. Due to their unique functionalities and the defined primary structure, these peptides are used for surface modification and attachment of various compounds that might be used for drugs and therapeutics [41, 42]. The ability of protein to form gels, emulsions, and dried particles, along with their capacity to synthesize NP with controlled size distribution, make them novel candidates for NP synthesis [43]. There are a number of proteins used for the NPs formulation: gelatin, elastin, collagen, gliadin, zein, ferritin, albumin, and silk protein (sericin and fibroin) [44-46].

By integrating principles from physics, engineering, chemistry, and biology, we have harnessed the capability to engineer biological nanomaterials at the molecular scale, utilizing self-assembling peptide systems. Peptides serve as the building blocks for creating a diverse array of nanostructures, including but not limited to nanofibers, nanotubes, vesicles, nanometer-thick surface coatings, and nanowires. Self-assembling peptides play multifaceted roles, ranging from stabilizing membrane proteins to creating favorable environments for cell growth and tissue repair in regenerative medicine. Moreover, they aid in gene and drug delivery, showcasing their versatility as tools for crafting sophisticated architectures, innovative materials, and nanodevices. These capabilities drive advancements in nanobiotechnology and various engineering disciplines. Positioned at the intersection of various disciplines such as chemistry, materials science, molecular biology, and engineering, molecular self-assembly harnesses nature's vast potential to advance across disciplines and enhance societal well-being. Nanofibers, elongated cylindrical structures measuring between 5 and 20 nm, possess a high surface-to-volume ratio that facilitates the incorporation of a wide array of bioactive molecules, including nucleic acids [47]. Among the peptides capable of self-assembly, examples include amyloid peptides, ionic self-complementary peptides, collagen-like triple helical peptides, and amphiphilic peptides, all of which can spontaneously organize into nanofibers [48].

Table 1.1 Overview of various strategies for biomolecule-nanoparticle integration.