Some chemical modifications aiming to introduce a new functionality, to
improve and/or develop a given property of chitosan are addressed. Given the great
number of possible reactions, focus is put only on some representative chitosan
derivatives, exploring examples of those exhibiting anionic, cationic, amphiphilic and
hydrophilic character, as well as on crosslinked derivatives. The main synthetic routes
used to produce such chitosan derivatives are discussed as well as their structural and
physicochemical characterization and some examples of applications in different fields.
The effects of the characteristics of the parent chitosan, the locus of chemical
modification, the nature and the content of substituent's on the properties of the
chitosan derivatives are discussed. Some applications of chitosan derivatives are
discussed as well.
Keywords: Amphiphilic derivatives, Anionic derivatives, Chitosan, Chemical
modifications, Cationic derivatives, Genipin-crosslinked N, O-carboxymehtyl
chitosan, N, O-carboxymehtylchitosan, N-(2-hydroxyl)propyl-3-trimethylchitosan,
N, N, N-trimethylchitosan, N, O-methoxypoly(ethyleneglycol)-g-chitosan.
