Hydrogels natural polymer

In summary, we described a system in which a backbone containing a highly polar group contains a degree of cross-linking. Put another way, the system is a three-dimensional network of water-soluble polymer and cross-linking that serves as the basis for all hydrogels, natural or synthetic. 

Liu L, Li PS, Asher SA (1999) Entropic trapping of macromolecules by mesoscopic periodic voids in a polymer hydrogel. Nature 397(6715) 141-144... 

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. 

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