Preparation method of biocompatible gamma-polyglutamic-acid hydrogel

The invention discloses a preparation method of biocompatible gamma-polyglutamic-acid hydrogel, which comprises the following steps of: by using polyglutamic acid as a main raw material and a biological-source material chitosan oligosaccharide as a cross-linking agent, carrying out preparation reaction in an aqueous solution, and activating a gamma-polyglutamic-acid carboxyl group by utilizing activating agents diamine carbide and N-hydroxysuccinimide ester to enable the polyglutamic acid and the free amino group of the chitosan oligosaccharide to form an amido bond to further form the hydrogel in a three-dimensional netted structure. After the prepared gel is swelled and balanced, drying is carried out by adopting a freeze-drying, vacuum-drying or microwave-drying mode. The biological-source material chitosan oligosaccharide is selected as the cross-linking agent, so that the biocompatibility of an obtained hydrogel system can be markedly improved; and a reaction system is an aqueous-solution system, reaction regulating and controlling properties are good, and the gel is stable. Because the hydrogel prepared by the method disclosed by the invention has good biocompatibility, the hydrogel can be widely applied to medicament carriers, auxiliary wound materials, medical and sanitary articles and the like.