Patentology of chitinous biomaterials. Part II: chitosan

Cationic chitosan is recognized as the most widely studied derivative of chitin, one of the main and the most evolutionary ancient structural biopolymer in nature. The multi-functionality of chitosan, due to its specific physicochemical properties, biodegradability and biocompatibility, is a fundamental factor in the patentability of this biopolymer in diverse fields of modern science and technology. It is shown that the chitosan-related patents were categorized mainly under biomedical, material science, biotechnology, and chemical directions; while a very small portion of the patents were mentioned under food, cosmetics, environmental protection, and agricultural fields. For the first time, the review provides a detailed analysis on the background and scope of the patents reported on chitosan so far.