The natural substance chitin, which is present in the shells of crustaceans including shrimp, crab, and lobster, is the source of chitosan, a biopolymer. It is a linear polysaccharide made up of N-acetyl-D-glucosamine and β-(1→4)-linked D-glucosamine units that are dispersed randomly. Because of its special qualities, which include biocompatibility, biodegradability, non-toxicity, and antibacterial activity, chitosan is well known for its numerous applications in a variety of industries, including medicines, agriculture, food, cosmetics, and environmental remediation. Chitosan has drawn a lot of interest from the pharmaceutical sector because of its potential as a medication delivery system. Because of its cationic properties, it can interact with mucosal surfaces that are negatively charged, which improves the absorption of medications across biological membranes. since of this characteristic, it is a great choice for the development of controlled-release drug delivery systems since it can target particular body regions with a low risk of systemic side effects. Furthermore, because of its hemostatic, antibacterial, and immunostimulatory qualities, chitosan demonstrates exceptional wound healing capabilities. Chitosan dressings encourage tissue regeneration and hasten the healing process by creating a barrier of defense over the wound site. Its antibacterial activity also aids in the prevention of infections, which makes it especially helpful in the treatment of burns and chronic wounds. Chitosan-based products are used in agriculture as biopesticides and biostimulants to increase crop sustainability and productivity. By promoting nutrient uptake, strengthening stress tolerance, and generating systemic resistance to infections, chitosan promotes plant growth. In addition, it functions as a natural substitute for synthetic pesticides, providing efficient pest management with less environmental contamination and toxicity hazards. Chitosan is used in the food business as a dietary supplement, clarifying agent, and food preservative. since of its antibacterial qualities, perishable goods have a longer shelf life since rotting microorganisms are prevented from growing. By eliminating proteins and suspended particles, chitosan can also be used as a fining agent to clear liquids like wine and juice. Chitosan-based formulas are also used in cosmetics because of its skin-rejuvenating, anti-aging, and moisturizing properties. They lessen wrinkles, smooth out the texture of the skin, and increase the effectiveness of other active substances in skincare products. All things considered, chitosan's extraordinary qualities and wide range of uses highlight how important it is as a sustainable biomaterial with enormous promise for resolving several societal and environmental issues.
