Chitosan
[CAS# 9012-76-4]

Identification

• Classification: Biochemical >> Carbohydrate >> Polysaccharide
• Name: Chitosan
• Synonyms: Poly(beta-(1,4)-2-amino-2-deoxy-D-glucose); Poly(beta-(1,4)-D-glucosamine)
• Molecular Formula: (C₆H₁₁NO₄)_n
• Molecular Weight: 50000-190000
• CAS Registry Number: 9012-76-4
• EC Number: 618-480-0

Properties

• Solubility: soluble (dilute aqueous acid)

Safety Data

• Safety Statements: S24/25

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335
Eye irritation	Eye Irrit.	2	H319

Discovery and Applications

Chitosan is a biopolymer derived from chitin, a naturally occurring substance found in the exoskeletons of crustaceans such as shrimp and crabs. Chitosan is obtained through the deacetylation of chitin, which involves removing acetyl groups from the chitin molecule to form a more soluble compound. The discovery of chitosan dates back to the 19th century, but its commercial use began in the mid-20th century. It gained attention due to its biodegradable, non-toxic, and biocompatible properties, making it suitable for various applications in the fields of medicine, agriculture, and food processing.

The most prominent application of chitosan is in the medical and pharmaceutical industries. It is used in drug delivery systems, particularly for controlled release formulations. Due to its ability to form gels and its biocompatibility, chitosan is often utilized as a carrier for drugs, vitamins, and other active compounds. Additionally, it has been explored as a wound healing agent due to its antimicrobial and anti-inflammatory properties. Chitosan can help accelerate the healing process by promoting tissue regeneration and reducing infection at the wound site.

In the food industry, chitosan has multiple applications due to its ability to act as a natural preservative. It can extend the shelf life of food products by inhibiting the growth of bacteria and fungi. Chitosan is often used in the production of food packaging materials that have antimicrobial properties, reducing the need for artificial preservatives. Its use as a fat replacer in low-calorie food formulations has also been studied, as chitosan can bind to fats and prevent their absorption in the digestive system. This has led to its use in dietary supplements aimed at weight loss, although the clinical evidence supporting its effectiveness for this purpose remains inconclusive.

In agriculture, chitosan is used as a biopesticide and a natural growth promoter. Its antifungal and antibacterial properties help protect crops from pathogens, reducing the need for chemical pesticides. Chitosan is also known to enhance plant growth and improve resistance to environmental stress, making it valuable in sustainable farming practices. It can be applied directly to crops or incorporated into soil treatments to promote healthy growth and increase yields.

Chitosan has also found applications in the cosmetics industry, where it is used in various skincare products. Its moisturizing, anti-aging, and skin-repairing properties make it a popular ingredient in creams, lotions, and masks. Chitosan helps retain moisture in the skin, providing hydration and improving skin texture. Additionally, its natural ability to form films on the skin helps protect against environmental pollutants and UV radiation.

Despite its wide range of applications, chitosan faces some challenges that limit its use. One of the main limitations is its solubility, as chitosan is not very soluble in water at neutral pH. Researchers have been working on improving its solubility and enhancing its functional properties to make it more effective in various applications. Additionally, the cost of production can be high, especially in large-scale manufacturing, due to the need for chitin extraction from crustacean shells.

Nevertheless, chitosan continues to be an important material in various industries due to its eco-friendly nature and versatile properties. As research into its applications expands, chitosan is expected to play a significant role in the development of sustainable and innovative solutions in health, food, and agriculture.

References

2025. In-vitro investigation of chitosan/polyvinyl alcohol/TiO2 composite membranes for wound regeneration. Biochemical and Biophysical Research Communications, 742.
DOI: 10.1016/j.bbrc.2024.151129

2025. Unlocking the potential of chitosan in immunoassay sensor. Carbohydrate Polymers, 339.
DOI: 10.1016/j.carbpol.2024.123024

2003. Production and Characterization of O/W Emulsions Containing Cationic Droplets Stabilized by Lecithin−Chitosan Membranes. Journal of Agricultural and Food Chemistry, 51(8).
DOI: 10.1021/jf020590f