What is Chitosan？

Chitosan is the product of N-deacetylation of chitin, chitin (chitin), chitosan and cellulose have similar chemical structure, cellulose is hydroxyl at C2 position, chitin and chitosan are replaced by an acetylamino group and amino group respectively at C2 position, chitin and chitosan have many unique properties, such as biodegradability, cellular affinity, and bioeffects, etc. Especially, it is the only alkaline polysaccharide among natural polysaccharides that contains free amino group. Chitosan, which contains free amino group, is the only alkaline polysaccharide among natural polysaccharides. [1]

The amino groups in the molecular structure of chitosan are more reactive than the acetylamino groups in chitin, giving the polysaccharide excellent biological functionality and the ability to undergo chemical modifications. Therefore, chitosan is considered a functional biomaterial with greater application potential than cellulose. [1]

Chitosan is the product of removing part of the acetyl group of the natural polysaccharide chitin, which has many physiological functions such as biodegradability, biocompatibility, non-toxicity, bacteriostasis, anticancer, lipid-lowering, and immune-enhancing, etc. It has been widely used in the fields of food additives, textiles, agriculture, environmental protection, beauty and health care, cosmetics, antimicrobials, medical fibres, medical dressings, artificial tissue materials, drug slow-release materials, gene transduction vectors, biological medical fields, medical resorbable materials, medical materials, and artificial tissues. It is widely used in the fields of food additives, agriculture, environmental protection, beauty care, cosmetics, antimicrobial agents, medical fibres, medical dressings, artificial tissue materials, drug slow-release materials, gene transduction carriers, biomedical applications, medical absorbable materials, tissue engineering carrier materials, medical treatment, drug development and other daily-use chemical industries.

A large amount of chitin exists in the shells of marine arthropods such as shrimps and crabs, the shells of insects, the cell membranes of fungi and algae, the shells and bones of molluscs and the cell walls of higher plants. Chitin is widely distributed in nature, reserves only after cellulose, is the second largest natural macromolecules, the amount of chitin biosynthesis of about 10 billion tons per year, is a recyclable renewable resources, inexhaustible, inexhaustible, these natural polymers of the main distribution of the coastal areas of India, Poland, Japan, the United States, Norway and Australia and other countries, chitosan has been commercially produced. [1]

Chitin (chitin) was first discovered in mushrooms in 1811 by Professor H. Bracolmot, a French researcher in the history of natural sciences, and named Fungine. 1823, another French scientist, Ogier, isolated the same substance from the wing-sheaths of crustacean insects and named it chitin; in 1859, French scientist C. Rouget immersed chitin in a concentrated KOH solution, boiled it for some time, removed it and washed it and found that it was soluble in organic acids; in 1894, Ledderhose, a German, confirmed that the modified chitin prepared by Rouget was chitin with some of the acetyl groups removed, and named it chitosan, or chitosan; in 1939, Haworth obtained an undisputed controversial synthetic method to determine the structure of chitin; in 1936, Rigby, an American, was granted a series of granted patents relating to chitin/chitosan, describing methods of isolating chitin from shrimp and crab shells, methods of preparing chitin and chitosan derivatives, and methods of preparing chitosan solutions, chitosan membranes, and chitosan fibres; in 1963, Budall proposed that chitin existed in three crystalline forms; in the 1970s, research on chitin increased; in the 1980s and 1990s, research on chitin/chitosan entered its heyday.