Hydrogels chitin/chitosan

Murakami, K., Aoki, H., Nakamura, S. et al. (2009) Hydrogel blends of chitin/chitosan, fucoidan and alginate as healing-impaired wound dressings. Biomaterials, 31(1), 83-90. 

Araki J, Yamanaka Y, Ohkawa K (2012) Chitin-chitosan nanocomposite gels reinforcement of chitosan hydrogels with rod-like chitin nanowhisktas. Polym J 44 713—717... 

Nagasawa, N., W acedil sikiewicz, J. M., Seko, N. et al. 2006. Metal adsorption of chitin/chitosan derivatives hydrogels crosslinked with irradiation. JAEA-Review 042 52-55. 

Chitin/chitosan hydrogel and porous scaffold Crabs, shrimp, krill Moist microenvironment maintained Blood vessels formation enhanced Granulation tissue increased Antimicrobial effects Fibroblast proliferation stimulated Murakami et al. (2010) and Liu et al. (2004)... 

Keywords Blends Chitin Chitosan Fibers Hydrogels Tissue engineering Wound dressing... 

Chitin is known to be biodegradable, biocompatible, and nontoxic. It is used in dmg delivery and bio medical applications. It also used in the purification of water especially for the absorption of toxic dyes. Chitin has limited solubility in solvents but chitosan is readily soluble in acidic aqueous solutions and has more tendency to be chemically modified. Chitosan can readily be spun into fibers, cast into films, or precipitated in a variety of micromorphologies from acidic solutions. Min and Kim have reported on the adsorption of acid dyes from wastewater using composites of PAN/chitosan [52]. Shin et al. has reported on copolymers composed of PVA and poly dimethyl siloxanes cross-linked with chitosan to prepare semi IPN hydrogels for application as biomedical materials... 

Chitin and chitosan Chitin hydrogel Lumber dorsal root Chitosan films Frier et al. 

Natural polymers have also been used as thermo-sensitive hydrogels, either on their own or in combination with other synthetic polymers. Popular natural polymers include chitosan, cellulose derivatives, dextran, xyloglucan and gelatin (Klouda and Mikos 2008). Chitosan is a polysaccharide derived from the shells of crustaceans and is produced by deacetylation of chitin, basically through the removal of the acetyl group using a concentrated NaOH solution (Fig. 11.5). The main advantage of chitosan for medical and pharmaceutical applications is its biocompatibility and inertness when in contact with human cells (Kumar et al. 

Blends or composites were also prepared especially by Hirano in the same way as mentioned previously for chitin [63], Other systems were proposed in the literature and listed previously [1, 2], Some of them are described in detail, for example, chitosan/ polyamide 6 and chitosan/polyamide 66 [119,120], chitosan/cellulose using a common solvent [121,122], chitosan/poly(oxyethylene) (POE) [123], chitosan/polyvinylpyrrolidone (PVP), chitosan/polyvinyl alcohol (PVA) [123,124], chitosan/polycaprolactone [124-126], chitosan/ collagen [127], chitosan/PHB [128], and chitosan/cellulose fibres [129]. In some case, the polymers are crosslinked in the blends [130]. Hydrogels or films have been prepared by mixing chitosan solution with monomers, initiator and cross-linker followed by copolymerization [131,132]. 

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