Synthesis and characterization of water-soluble O-succinyl-chitosan

The efficient procedure to prepare novel water-soluble O-succinyl-chitosan was established by using one three-step reaction. Phthaloyl group was firstly chosen as the protection group for the amino group of chitosan, and O-succinylation was then completed. Protection group was removed finally by using hydrazine hydrate. The chemical structure of the modified chitosan was characterized by FTIR, 1H-NMR, 13C-NMR and elemental analysis. Some physical properties were analyzed by X-ray diffraction, differential scanning calorimetry (DSC), thermogravimetry (TG) and solubility test. It indicates that after O-succinylation, the modified chitosan shows much better solubility in water. The study of enzymatic degradation showed that the O-succinyl-chitosan was of low susceptibility to lysozyme. O-succinylation-chitosan is a useful intermediate, which permits further chemical modification for amino group and may be have potential applications in biomedical system.