Abstract
Chitosan is a product of the deacetylation of chitin, which is widely found in nature. Chitosan is insoluble in water and most organic solvents, which seriously limits both its application scope and applicable fields. However, chitosan contains active functional groups that are liable to chemical reactions; thus, chitosan derivatives can be obtained through the chemical modification of chitosan. The modification of chitosan has been an important aspect of chitosan research, showing a better solubility, pH-sensitive targeting, an increased number of delivery systems, etc. This review summarizes the modification of chitosan by acylation, carboxylation, alkylation, and quaternization in order to improve the water solubility, pH sensitivity, and the targeting of chitosan derivatives. The applications of chitosan derivatives in the antibacterial, sustained slowly release, targeting, and delivery system fields are also described. Chitosan derivatives will have a large impact and show potential in biomedicine for the development of drugs in future.
Highlights
With the improvement of living standards, people have been paying more attention to the development of health and medical technology
The water-soluble amphoteric chitosan derivative (CTAA) is formed by using trimellitic acid chloride, where CTAA is crosslinked with alginate to prepare a film and the CTAA/alginate film can protect 5-FU from being absorbed and degraded by the upper gastrointestinal tract before reaching the colon [109]
Fatty-acid-modified quaternary ammonium chitosan derivative nanoparticles were used as a carrier to deliver insulin into the liver, and the results showed that the nanoparticles had a higher hepatocyte uptake and a better anti-diabetic efficacy [80]
Summary
With the improvement of living standards, people have been paying more attention to the development of health and medical technology. Chitosan is a deacetylated product of chitin, which is an abundant natural resource that features less storage than cellulose [4,5]. Chitosan is a renewable natural alkaline polysaccharide that has no toxicity and no side effects, and it features good moisturizing and adsorption properties. Chitosan derivatives can be obtained by the chemical modification of chitosan-reactive functional groups. Chemical modification can improve the physical and chemical properties of chitosan, it can retain the unique properties of chitosan and expand the application range of chitosan derivatives. Modification of Chitosan Functional groups on the chitosan molecules include C3–OH, C6–OH, C2–NH2, and acetyl amino and glycFousnicdtieonbaolngdrosu[p6s].onAtmheocnhgitothsaenmm, tohleecualceestiynlcalumdienCo3–bOoHnd, Ci6s–OasHs,tCa2b–lNe Has, tahned gaclyetcyolsaidmiicnobond, wstehriawsictcnhehdhriiicsicghnnlhdyioiscrntoandsenoriatacdsneeeyacibsestyooisnstofodsrboasfrci[bagt6cui]gtt.ruhetArah.etma.CtiCot3in3t–d–gOdoOoeHtHhessebnbmneeooll,toottennheagaegssssiaitllctoyyoeatrrayeeslaasecacectmotc..onTiTdnnhhoadereaybaraocyhtcniytvhdidevyriedsochxrcaoeyhsmxle,symiitctla,acbiilcalteanpclnraaoposnptrnteorhroopetttieaegrrtsoletyiotefcafrsoteCeseoi6ldff–yriOC,ecaeH6bnl–yodOa,nnaiHdtdns, danitds C2–CN2–HN2Hta ktaekaedavdavnatnatgageeooffththeessee ggrroouuppss iinn cchhiittoossaannmmoloelceucluesletsotiontirnotdroudceuocethoerthgerrougprosuthprsouthgrhough varivoaursiokuisndkisnodfsmofomleoculelcaurldaresdiegsnig.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
