Chitosan: modification and biodegradability of by-products

Chitosan has so far been the only identified naturally occurring cationic polymer that is alkaline of alkaline origin; it is derived from chitin. Along with having excellent biological activities like hemostasis, antioxidant and antibacterial activity, it also has tremendous properties like cell affinity, good biodegradability and biocompatibility. Chitosan's limited water solubility limits its broad applicability. Nonetheless, its range of applications can be increased by enhancing its solubility and biological activity via chemical adjustments of the composition of its matrix. Different ways that chitosan can be chemically modified, as well as its primary functions and the advancement of application research, were examined. Electrospun chitosan nanofibers with random or aligned fiber structure can further be cross-linked by physical, chemical and ionic crosslinking methods. Chitosan-based materials are suitable inks for 3D/4D (bio)printing and their applicability in creating advanced drug delivery platforms and tissue-engineered constructs. Overall, there has been significant advancement in modifying chitosan as well as the use of its by-products, including the synthesis of numerous unique multifunctional chitosan derivatives, new synthetic pathways and optimization of conditions. Because modified chitosan typically has better chemical properties than unaltered compound, its by-products (modified) showing greater potential for biological properties are more widely utilized. In order to lay the groundwork for future chitosan development and application, this paper will examine the recent advancements in technologies that chemically modify chitosan as well as the applications of the compound and its by-products in a variety of industries, such as textiles and pharmaceuticals.