A review on chitosan and its nanocomposites in drug delivery

[Display omitted] •Cs has good biocompatibility, biodegradability and low toxicity.•Cs-nanocomposite shown enhanced efficacy in targeted drug delivery.•A comprehensive overview of Cs and Cs-nanocomposite in drug delivery. Chitosan the second most abundant next to cellulose, naturally occurring amino polysaccharide, derived as a deacetylated form of chitin. Its nontoxic, biocompatible, antibacterial and biodegradable properties have led to significant research towards biomedical and pharmaceutical applications, such as drug delivery, tissue engineering, wound-healing dressing etc. The primary amine group in chitosan are responsible for its various properties such as cationic nature, controlled drug release, muco-adhesion, in situ gelation, antimicrobial, permeation enhancement etc. This review discusses the various forms of chitosan materials such as beads, films, microspheres, nanoparticles, nanofibers, hydrogels, nanocomposites, etc. as drug delivery device and attempted to report the vast literature available on chitosan based materials in drug delivery applications. Moreover, chitosan derivatives and chitosan nanocomposites with different nanofillers and its application in drug delivery have also been reviewed.