Chitosan is derived from a natural product, chitine, quite abundant in shrimps shells.

Chitin is a non toxic, biodegradable polymere of high molecular weight. After cellulose, it is the most common polysaccharide found in the nature. Like cellulose, chitine is a fiber, and in addition, it presents exceptional chemical and biological qualities that can be used in many industrial and medical applications.

Chitin and chitosan have the same chemical structure. Chitin is made up of a linear chain of acethylglucosamine groups. Chitosan is obtained by removing enough acethyl groups (CH3-CO) for the molecule to be soluble in most diluted acids. This process, called deacetylation, releases amine groups (NH) and gives the chitosan a cationic characteristic. This is especially interesting in an acid environment where the majority of polysaccharides are usaually neutral or negatively charged.

CHITIN	CHITOSAN