Chitosan is a natural biopolymer derived from Chitin, which is the second most abundant natural polysaccharide after cellulose. Chitin is primarily found in the exoskeletons of crustaceans such as crabs, shrimps, and lobsters, as well as in the cell walls of fungi. To produce chitosan, chitin is subjected to a deacetylation process, which involves the removal of acetyl groups. This process transforms the chitin into chitosan, making it soluble in acidic solutions, unlike chitin which is not.

Chitosan has several unique properties that make it valuable across various industries. It is biodegradable, biocompatible, non-toxic, and has antimicrobial, antifungal, and chelating properties.The primary source of commercial chitosan is the seafood industry, which provides a large amount of chitin-rich shell waste. This makes chitosan an environmentally friendly product by valorizing waste materials. There's ongoing research to improve the extraction and production processes of chitosan to enhance its properties and increase its applications.