The Effect of Irradiation Degradation of Chitosan with Gamma-Ray on the Enzymatic Degradability in Vitro of Chitosan-Based Biomembrane

The degraded chitosans were obtained with the irradiation of aqueous chitosan/HAc solution by using gamma-ray, their viscosity average molecular weights and degrees of deacetylation were determinated with dilute solution viscometry and elemental analysis method, respectively. Four biomembranes prepared separately from chitosans with different viscosity average molecular weight were soaked in aqueous lysozyme/phosphate buffer, and their percentages of weight loss in different time were recorded. The research result indicated that the viscosity average molecular weight of degraded chitosan decreased as the dosage of ⁶⁰Co gamma-ray increased, but degrees of deacetylation retained constant. The percentage of weight loss of chitosan-based biomembrane in lysozyme/phosphate buffer increased as time increased, and increased as molecular weight decreased. It´s feasible to improve the biodegradability of chitosan-based biomembrane by lowering the molecular weight of corresponding chitosan.