Sogol Motallebi tala tapeh - Department of Chemical Engineering, Ayatollah Amoli Branch, Islamic Azad University, Amol, Iran
Fatemeh Hosseinzadeh - Department of Chemical Engineering, Mazandaran University of Science and Technology, Babol, Iran
Hannaneh Hosseinzadeh - Department of Chemical Engineering, Babol Noshirvani University of Technology, Babol, Iran
Hamed Mehtarifar - Department of Chemical Engineering, Mazandaran University of Science and Technology, Babol, Iran

Chitin is a linear polysaccharide that is made up of β-(1, 4)-linked N-acetyl-D-glucosamine units. Although chitin has many significant properties, because of its limited solubility, chitosan has been given more attention. Chitosan is a natural polymer that is derived from chitin by chemical processes. Recently, chitosan has played an important role as a natural and biological polymer in various systems. Chitosan, due to its significant properties such as biological compatibility, biodegradability, non-toxicity, non-microbial, high solubility, flexibility, hydrophilicity, pH sensitivity, anticancer property, ease of synthesis and convert to various structures including nanoparticles, microparticles, scaffolds, biofilms, and hydrogels has been considered in biological systems. Furthermore, chitosan has the ability to combine with other materials, such as alginates, lignin, gelatin, silica, and various non-polar polymers such as polyethylene, because of its various functional groups (NH2 and OH). On the other hand, the application of this polymer in biomedical science included cell therapy, implant, wound dressing, tissue engineering, bone cartilage regeneration, composite membranes, cosmetology, and drug delivery in oral and injection methods has been added to its importance. The purpose of this study is to introduce the structure and properties of chitosan and investigate its presence in biological systems and medical sciences.

Chitosan, Drug Delivery, Biological Systems, Application