A natural long-chain polymer, chitin is the main component of the cell walls of fungi, the exoskeletons of arthropods (including crustaceans and insects), the radulas of mollusks, and the beaks and internal shells of cephalopods. However, marine crustacean shells are the primary sources of the chitin derivative chitosan. Chitin and chitosan are useful for various biological and biomedical applications, although they have been limited by poor solubility in the past. Current research focuses on increasing their solubility and bioactivity through molecular modifications. The resulting derivati |