Vigilancia Tecnológica

Disclosed in the present invention are a physical gel on the basis of a zwitterionic modified polysaccharide and a preparation method therefor. The method comprises the following steps: (1) preparing a macromolecular initiator (D-Br); (2) preparing a zwitterionic grafted modified polysaccharide derivative; and (3) preparing a physical gel on the basis of a zwitterionic modified polysaccharide. In the present invention, the control of the degree of polymerization n can be achieved by means of using the ATRP method of high molecular polymerization, so that the degree of polymerization of zwitterionic side chains is precisely regulated and controlled, and the magnitude of the ion interaction force is further controlled. Therefore, the phase transformation of "solution-gel-precipitation" of the polymer in a gradient salt ion solution is achieved. A prescription having sensitivity for a physiological solution is screened, and a biodegradable zwitterionic polysaccharide-based hydrogel is prepared.