Chitosan

DescriptionChitosan is a unique basic polysaccharide obtained by N-deacetylation of chitin in an alkaline medium. This alkaline consists mainly of β-(1-4)-2-acetamido-2-deoxy-D-glucose units. Besides, it is the second most abundant biopolymer on Earth after cellulose that can be found in crustacean shells and the cell walls of fungi. Another feature of chitosan is that it is a copolymer of N-acetyl-D-glucosamine and D-glucosamine. Protonation of the NH2 functional group on the C-2 position of the D-glucosamine repeating unit makes it easily soluble in aqueous acidic media and it results in the conversion of the polysaccharide to a polyelectrolyte in acidic media. Chitosan shows more potential than chitin for use in different applications as a result of the presence of its NH2 groups. It has good properties including biodegradability, biocompatibility, and antibacterial activity. Chitosan has abundant applications in different fields because it is the one and only pseudonatural cationic polymer. Generally it is prepared by deacetylation of α-chitin using 40%-50% aqueous alkali solution at 100℃-160℃. This preparation takes a few hours. As a result of this, newly derived chitosan has a degree of deacetylation (DD) up to 0.95.Chitosan is provided with high adsorption capacity and selectivity by many -NH2 and -OH groups that can chelate heavy metal ions. The intermolecular and intramolecular hydrogen bonds are numerous in chitosan molecules. The packing structure of chitosan in the three unit cell directions stabilizes strongly and gives the power to chitosan not to melt at all. Chitosan dissolves only in certain organic acids, like formic, acetic, propionic, lactic, citric, and succinic acids, and in some inorganic solvents, like hydrochloric, phosphoric, and nitric acid.

UsesChitin and chitosan are natural biopolymers that have various properties such as antimicrobial activity, hemostatic agent, metal-chelating, molecular affinity, and wound-healing agent. For a wide range of uses of these polymers, different modifications have been studied by different researchers. Electrospun fibers of chitin and chitosan could therefore be of great interest in various application fields such as tissue engineering, biomedical, cosmetics, and many industrial applications, such as wastewater treatment.Chitosan has various effects such as improving immunity, activation of cells, preventing cancer, lowering blood pressure, lowering blood pressure, anti-aging and regulating body environment. It can be used in medicine, health care and food fields.In the field of environmental protection, chitosan can be used in sewage treatment, protein recovery, and water purification. In functional materials, the chitosan can be used in film material, carriers, adsorbents, fibers, medical materials and the like. In the field of light textile, chitosan can be used for fabric finishing, health underwear and paper additives. In the field of agriculture, it can be applied to feed additives, seed treatment, soil improvement, and preservation of fruit. In the field of tobacco, tobacco Chitosan is an excellent sheet gel and can also improve the taste with being non-toxic and odorless upon burning.

OccurrenceChitosan comes from the shell of marine crustaceans.

UsesForms gels with multivalent anions. Gives clear solutions that dry to strong, clear films.Flocculant, protein precipitation, encapsulating agent and aqueous thickener.Chitosan is a natural polycationic linear polysaccharide derived from chitin. The low solubility of chitosan in neutral and alkaline solution limits its application.Chitosan: An Update on Potential Biomedical and Pharmaceutical Applications

UsesIdeal for wound healing and hemostasis; biosurgery and ophthalmology; scaffold and cell therapy; and drug delivery and vaccines

Useschitosan is a film-forming polysaccharide that can aid the skin’s moisture content and moisture-retention capacity by preventing transepidermal water loss. In addition, it appears to help bind other ingredients (for example, to increase liposome stability), thereby increasing the availability of active ingredients to the skin. Anti-bacterial properties are also associated with chitosan, as well as an ability to enhance the microbiological stability of a preparation. Some studies show that it can help improve the water-resistance properties of sun protection creams and lotions, and the longevity of a fragrance’s scent (the perfume adheres more strongly to the skin and evaporates more slowly, over a longer period). It acts as a skin conditioner, improving skin softness and suppleness. It may be found in moisturizers, sunscreens, and acne preparations, in addition to hair care products. It is the decarboxylated form of chitin and can hold water without creating a feeling of tackiness in a cosmetic preparation. According to some chitosan suppliers, the use of shrimp shells is one of the most important sources. They consist of 30–35 percent protein, 30–35 percent minerals, and 15–20 percent chitin, with some traces of lipids, dyes, and soluble proteins.

General DescriptionChitosan is a linear amino polysaccharide composed of approximately 20% β1,4-linked N-acetyl-D-glucosamine (GlcNAc) and approximately 80% β1,4-linked D-glucosamine (GlcN) that is prepared by the partial deacetylation of chitin in hot alkali.