Nano polysaccharides

Above we have shown the attractiveness of the so-called green nanocomposites, although the research on these materials can still be considered to be in an embryonic phase. It can be expected that diverse nano- or micro-particles of silica, silicates, LDHs and carbonates could be used as ecological and low cost nanofillers that can be assembled with polysaccharides and other biopolymers. The controlled modification of natural polymers can alter the nature of the interactions between components, affording new formulations that could lead to bioplastics with improved mechanical and barrier properties. 

Pramendra Kumar is an Assistant Professor in the Chemistry Department at M.J.P. Rohilkhand University, Bareilly. He obtained his Master of Science from C.C.S. University, Meerut and Master of Engineering from Delhi College of Engineering. His research interests include modification of polysaccharides, synthesis of multifunctional nano materials and synthesis of nano bio-composites for their various applications e.g. water remediation, enzyme immobilization and other adsorbent applications. 

Krause, K. Girod, M. Chankvetadze, B. Blaschke, G. Enantioseparations in normal- and reversed-phase nano-high-performance liquid chromatography and capillary electrochromatography using polyacrylamide and polysaccharide derivatives as chiral stationary phases. J. Chromatography A 1999, 837 (1-2), 51-63. 

CHI 09] Chivrac F., Pollet E., Averous L., Progress in nano-biocomposites based on polysaccharides and nanoclays . Materials Science and Engineering R Reports, vol. 67, no. l,pp. 1-17,2009. 

Francius, G., Lebeer, S., Alsteens, D., Wildling, L., Gruber, H. J., Hols, R, De Keersmaecker, S., Vanderleyden, J, and Dufrene, Y. F. 2008. Detection, localization, and conformational analysis of single polysaccharide molecules on live bacteria, Acs Nano 2,1921-1929. 

Thus, among various organic materials cellulose is the most appropriate for preparation of various types of nano-materials, since this most abundant semicrystalline polysaccharide has a nanostructured organization that promotes the isolation of free nanoconstituents such as nanofilaments, nanofibrils, crystalline, and ANP. 

Colorimetric assays are appropriate methods to investigate protein interactions with cationic polysaccharide materials. However, these assays cannot differentiate between different types of interactions, i.e. adsorption and absorption of proteins. Among these, the bicinchoninic acid assay (BCA) is widely used since it allows an easy determination of the total amount of adsorbed proteins on bulk materials." The assay is based on the reduction of Cu to Cu in a reductive environment in the presence of proteins. The BCA chelates Cu, forming a colored complex whose absorption band at 562 nm can be related to the amount of adsorbed proteins on the materials. Using this method, it has been demonstrated that the incorporation of inorganic materials such as hydroxyapatite (HAP) or nano-HAP into chitosan-based materials leads to the formation of protein-rich layers at the... 

Recently, the greatest growth has been achieved in the structmed determination of natural polysaccharides, and hence this has increased our understanding in relation to structural features as well as functionahties of polysaccharides [1]. The basic knowledge of the structural feature of polysaccharides is essential toward the application as fundamental nanomaterials. For example. X-ray diffraction patterns of various natural polysaccharides have revealed that some of them adopt well-defined helical nanoarchitectures such as polynucleotides, which have never been produced through an artificial polymerization reaction, encouraging us to pursue the possibiUties of natural nano tubes. 

Polymer nano- or microparticles/microcapsules used in biomedical fields are fabricated from biocompatible biodegradable polymers. The list of these materials includes both natural materials, such as natural polysaccharides (alginate, cellulose, and chitosan as well as their many derivatives, etc.) and synthetic polymers. Natural polymers are attractive for cell immobilization due to their abundance and apparent biocompatibility. Synthetic polymers are used because of the high degree of control over the structure. Unlike natural materials, whose properties can vary from batch to batch, synthetic polymers provide highly consistent starting materials for any encapsulation technique. 

Starch is the main form of stored carbohydrate in plants. Starch is composed of a mixture of linear polysaccharide-amylose and highly branched polysaccharide-amylopectin. Both forms of starch are polymers of d-D-Glucose. A study of de Carvalho et al. on the preparation of TPS nanocomposites using nano-kaolin by melt intercalation technique in a... 

Iwamoto S, Nakagaito AN, Yano H (2007) Nano-fibrillation of pulp fibres for the processing of transparent nanocomposites. Appl Phys A-Mater Sci Process 89 461-466 Klemm D, Schumann D, Kramer F, Hessler N, Homung M, Schmauder HP, Marsch S et al (2006) Nanocelluloses as innovative polymers in research and application. Polysaccharides 205 49-96... 

Dufresne AJ (2006) Comparing the mechanical properties of high performance polymer nanocomposites from biological sources. J Nanosci Nanotechnol 6 322-330 Dufresne A (2008) Polysaccharide nano crystal reinforced nanocomposites. Can J Chem 86 484—494 Dufresne A, Vignon M (1998) Improvement of starch film performances using cellulose microfibrils. Macromolecules 31 2693-2696... 

Munigan R, Ramakrislma S (2004) Bioresorbable eomposite bone paste using polysaccharide based nano hydroxyapatite. Biomaterials 25 3829-3835... 

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