Natural biopolymers chitosan

Kumar,G. Buchheit, R G. (2005). Development and Characterization of Corrosion Resistant Coatings using Natural Biopolymer Chitosan. Electrochemical Society Transactions, Vol. 1, No. 9, (October 2005), pp. 101-117, ISSN 1938-6737... 

In view of the conductive and electrocatalytic features of carbon nanotubes (CNTs), AChE and choline oxidases (COx) have been covalently coimmobilized on multiwall carbon nanotubes (MWNTs) for the preparation of an organophosphorus pesticide (OP) biosensor [40, 41], Another OP biosensor has also been constructed by adsorption of AChE on MWNTs modified thick film [8], More recently AChE has been covalently linked with MWNTs doped glutaraldehyde cross-linked chitosan composite film [11], in which biopolymer chitosan provides biocompatible nature to the enzyme and MWNTs improve the conductive nature of chitosan. Even though these enzyme immobilization techniques have been reported in the last three decades, no method can be commonly used for all the enzymes by retaining their complete activity. 

Chitosan Chitosan has a molecular structure similar to cellulose. This material is produced from chitin, which is widely found in the exoskeleton of shellfish and crustaceans. Chitin is the second most abundant natural biopolymer after cellulose. Chitosan is a good adsorbent for all heavy metals. It has been estimated that chitosan can be produced from shellfish and crustaceans at a market price of 15.43 /kg. 

We used the crosslinked chitosan fiber (hereafter called ChF) in this experimental study. ChF was fabricated by Fuji Spinning Co., Japan. Fig.l shows the unit molecular structure of chitosan which was transformed from chitin by deacetylation. Chitin is a natural biopolymer which is contained in the shell of arthropods. Chitosan was crosslinked to make an adsorbent with acid, alkaline, and chemical proofs. The fabrication method of ChF was presented elsewhere.[S,6]. 

Chitosan is a biocompatible and biodegradable natural biopolymer, with applications in food processing, agriculture, biomedicine, and biotechnology. Chitosan... 

Chitin is an abundant natural biopolymer and exhibits excellent antimicrobial properties. To obtain enhanced antimicrobial properties, deacetylated products of chitin—chitosan (CS) have to be synthesised, which includes the introduction of alkyl groups to the amine groups to produce quaternised N-alkyl CS derivatives, the introduction of extra quaternary ammonium grafts to CS and modification with phenolic hydroxyl moieties. 

Chitosan is a natural biopolymer that has many desirable characteristics as a scaffold or encapsulation material. It is a biodegradable, semicrystalline polysaccharide obtained by A-deacetylation of chitin, which is harvested from the exoskeleton of marine crustaceans. Chitosan is composed of glucosamine and A-acetyl glucosamine which are linked by glycosidic bonds. Being structurally similar to ECM components, chitosan provides cell-ECM interactions which guide cell behavior. 

As mentioned previously, because of the polycationic nature of chitosan in acidic media, the biopolymer may be intercalated in sodium montmorillonite through cation exchange and hydrogen-bonding processes, the resulting nanocomposites showing interesting structural and functional properties. 

Cationic lipids and cationic polymers are designed as gene delivery systems on the nanoscale. Especially chitosan is under focus as a biodegradable, natural biopolymer, used both as the polyplex and also as a coating material for other polyplexes. Chitosan-coated poly(isohexyl cyanoacrylate) nanoparticles have also been developed for intravenous delivery of siRNA and no evidence of toxicity was observed after intravenous administration for 30... 

Of the natural biopolymers, polysaccharides seem to be the most promising materials for various biomedical fields. They can be obtained from various sources, including animals, plants, algae and microorganisms. Chitosan (CHT) is the most commonly used polysaccharide, due to its chemical structure [1-12]. 

Ahmad A.L., Sumathi S., Hameed B.H., Chitosan A natural biopolymer for the adsorption of residue oil from oily waste-water, Adwrjc>/. ScL Technol., 22(1), 2004, 75-88. 

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