Chitosan [α (1–4) 2-amino 2-deoxy β-D glucan], a copolymer of glucosamine and N-acetylglucosamine. Chitosan is obtained by deacetylation of chitin, a naturally abundantly available polymer (e.g. in crustaceans). Chitosan nanoparticles (CS-NPs) have provided the opportunities for the site-specific delivery of drugs because they can solubilize various hydrophobic drugs, increase bioavailability and stay long time in blood circulation system