Ahuekwe, E. F.Akinhanmi, Fadekemi O.Akinyemi, O D.Taiwo, O. S.Popoola, T. S.George, D. S.Aladele, A. K.Azeta, J.Oniha, M. I.2026-03-262025https://repository.covenantuniversity.edu.ng/handle/123456789/50706Chitin and chitosans, derived from diverse natural sources, are polysaccharides that have numerous uses in the food, biomedicine, water treatment, and pharmaceutical industries. As a result, the USD 6.8 billion chitosan market saw significant expansion in 2019. Their complex biological characteristics and therapeutic potential are methodically examined in this review, which also highlights their noteworthy antibacterial, antioxidant, and antiinflammatory effects. Even with these praiseworthy qualities, regulatory bodies place restrictions on their recognition as medicinal products. Chitosan is also the best option for creating nanoparticles due to its qualities including biocompatibility, biodegradability, and positive surface charge. The exploration of natural sources highlights extraction strategies and reveals source-specific procedures using a variety of spectroscopic and microscopy techniques. Chitosan-based nanoparticles (ChNPs) are particularly effective in the field of biomedical applications; they work well in tissue engineering, gene therapy, and medication delivery. Their adaptability encompasses a range of aspects, such as the delivery of drugs, antibiotics, polyphenols, vaccines, and gene therapy. A thorough examination of the toxicity and biocompatibility of ChNPs is provided in this review, highlighting the effects of deacetylation degree, structural characteristics, molecular weight, cytotoxicity, and cellular uptake. A close examination is given to the factors impeding the application of biomedicine, highlighting the critical need for regulatory frameworks. While chitosan’s symphony of applications reverberates throughout a multitude of biomedical fields, continued research and development endeavors are essential for revolutionizing uses and guaranteeing their prudent integration into a variety of sectorsenArticle