Nanochitosan and the Skin

Chitosan is a non-toxic, biodegradable, polycationic polysaccharide, easily obtained from the naturally abundant chitin from the exoskeleton of crustaceans (Fig. 9.1) through deacetylation (partial, typically 66–95 %) and partial depolymerization (less extensive). It is a polymeric 2-amino-2-deoxy-β-D-glucan formed through 1→4 glycosidic linkages. The interest in chitosan as delivery vehicle for active species was generated by the knowledge that it is broken down by the enzyme lysozyme in the human body releasing harmless amino sugars [1], hence biocompatible. The rate and extent of its biodegradability depends on its degree of deacetylation (DD), slower for higher DD values [2].