Preparation and characterization of N-chitosan as a wound healing accelerator.

Chitosan is insoluble in water due to its rigid crystalline structure, which has significantly restricted its application in wound healing. The objective of this study was to synthesize a water-soluble chitosan derivative, N-succinyl-chitosan (NSC), and evaluate its ability to accelerate the wound healing process. NSC was synthesized with succinic anhydride, hydrochloric acid, and alkaline chitosan under optimized conditions, and characterized using Fourier transform infrared, proton nuclear magnetic resonance, and X-ray diffraction spectroscopy; thermal gravimetric analysis; and a solubility test. The cytotoxicity of NSC was investigated in L929 cells, and its antibacterial activity was evaluated by the inhibition zone method and bacterial growth curves analysis. The results showed that the solubility of NSC was substantially improved compared to chitosan, and NSC was non-toxic with good antibacterial properties. An animal wound healing test indicated that NSC could significantly reduce the healing time compared to chitosan. Histopathological examination suggested that the underlying mechanisms of these effects were related to NSC's ability to promote the formation of granulation tissue and enhance epithelialization. Collectively, these results demonstrate the good potential for NSC to be applied as a wound dressing material.