At one point in your life, you must have eaten lobster, shrimp, prawn, clam, crab and other foods belonging to this group. Do you know that these foods, especially their shells, are a great source of chitosan? Yes, they contain chitosan, a biopolymer that has a variety of uses such as wound healing, tissue engineering and tissue repair, as well as local delivery of cells, drugs, proteins, genes and other therapeutic uses. 

These biomedical applications are discussed when you talk about chitosan chemistry. Here are some of the details: 

The Production of Chitosan 

According to some chitosan chemistry resources, chitosan is formed through N-deacylation of the chitin molecule.  Note that chitosan is a linear polysaccharide composed of randomly distributed B-(1®4)-linked D-glucosamine (deacetylated unit; D) and N-acetyl-D-glucosamine (acetylated unit; A).  With this composition, chitosan is produced commercially by deacetylation of chitin, which according to chitosan chemistry resources is the structural element in the exoskeleton of crustaceans.    The degree of deacetylation (%DA) can then be identified by NMR spectroscopy, and the %DA in commercial chitosan is in the range of 60 to 100 percent 

For more helpful information about this topic, visit Dalwoo.com. This site contains a comprehensive illustration as to how chitin or chitosan is produced. 

The Amino Group in Chitosan 

According to some chitosan chemistry studies, chitosan contains an amino group which has a pKa value of ~6.5. This means that chitosan is positively charged and soluble in acidic to neutral solution, with a charge density dependent on pH as well as %DA-value.  With this information, it is concluded that chitosan is bio-adhesive and readily binds to negatively charged surfaces like the mucus membranes.  Furthermore, chitosan has the ability to enhance the transport of polar drugs across the epithelial surfaces.  With that, chitosan is found biocompatible and biodegradable. 

Chemical Properties of Chitosan 

Chitosan has some chemical properties which include: 

• Linear polyamine (poly-D-glucosamine)
• Reactive amino groups
• Chelates many transitional metal ions
• Basteriostatic and fungistatic effect
• Separations of protein
  

Application of Chitosan 

Chitosan has many great benefits. The field of health care, agriculture, cosmetics, waste and water treatment, food and beverage are given a bright future with the discovery of chitosan. Chitosan popularity has expanded greatly in recent years, thus it poses a potential for exploitation in several markets.