Nanomaterials biological

Because of the combined influence of the alignment and pitch of the helical modulation in different states, the material acquires a photonic band gap. The self assembled bio-derived photonic crystals thus have attractive optical properties for which CNC films are considered for development of newer materials for novel application. Especially the helical arrangement of the nanorods, converts these to materials with higher application potential in the field of optoelectronics. Such kind of films has attractive optical properties and possibly can be used in applications such as security papers and mirrorless lasing. Biological nanomaterials are also biodegradable. 

The poor dispersibility of CNTs in biological media can affect both the cytotoxicity [38] and the in vivo toxicity [39] of such nanomaterials. 

Studies on the use of hydrothermal, microwave-assisted, and reflux synthesis methods for the development and application of nanomaterials have been reviewed. An important aspect of the green synthesis of metallic nanopartides involves techniques that make use of biological materials such as plant extracts and microorganisms. The design of nanomaterials and control of their desired properties have been reviewed. The unique properties of manufactured nanomaterials offer many potential benefits. 

As mentioned earlier, biological systems have developed optimized strategies to design materials with elaborate nanostructures [6]. A straightforward approach to obtaining nanoparticles with controlled size and organization should therefore rely on so-called biomimetic syntheses where one aims to reproduce in vitro the natural processes of biomineralization. In this context, a first possibility is to extract and analyze the biological (macro)-molecules that are involved in these processes and to use them as templates for the formation of the same materials. Such an approach has been widely developed for calcium carbonate biomimetic synthesis [13]. In the case of oxide nanomaterials, the most studied system so far is the silica shell formed by diatoms [14]. 

Kumar, C. (2006) Biological and Pharmaceutical Nanomaterials, Wiley-VCH,Weinheim. 

Protein is an excellent natural nanomaterial for molecular machines. Protein-based molecular machines, often driven by an energy source such as ATP, are abundant in biology. Surfactant peptide molecules undergo self-assembly in solution to form a variety of supermolecular structures at the nanoscale such as micelles, vesicles, unilamellar membranes, and tubules (Maslov and Sneppen, 2002). These assemblies can be engineered to perform a broad spectrum of functions, including delivery systems for therapeutics and templates for nanoscale wires in the case of tubules, and to create and manipulate different structures from the same peptide for many different nanomaterials and nanoengineering applications. 

Bio-nanomaterials are significantly different from traditional larger biomaterials (e g., implants or microparticles as mentioned earlier) in terms of their physical and biological properties. Due to their new set of biological and physical properties, bio-nanomaterials also show potential for use as therapeutics and in dmg delivery systems. For instance, Na and coworkers in 2007 used a bio-nanomaterial, heparin/... 

Dutta D, Sundaram SK, Teeguarden JG, Riley BJ, Fifield LS, Jacobs JM, Addleman SR, Kaysen GA, Moudgil BM, Weber TJ (2007) Adsorbed proteins influence the biological activity and molecular targeting of nanomaterials. Toxicol. Sci. 100 303-315. 

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