Preparation method of astragalus polysaccharide injection with higher stability and activity

The invention discloses a preparation method of an astragalus polysaccharide injection with higher stability and activity and belongs to the technical field of medicines. The preparation method comprises steps as follows: 1) raw materials are weighed according to a formula; water for injection is added to astragalus polysaccharide and stirred uniformly under the condition that the temperature is 30-38 DEG C to obtain an astragalus polysaccharide solution; 2) a surfactant and a bacteriostatic agent are sequentially added to the astragalus polysaccharide solution and stirred uniformly under thecondition that the temperature is 40-50 DEG C; first filtration is performed after the mixture is left to stand for 1-2 h, and filtrate 1 is taken; 3) N2 or CO2 is introduced into a current treatmentdevice for pretreatment for 10 min; a stabilizer is added to the filtrate 1, and the mixture is put in a current treatment device for electrical treatment and left to stand for 30 min after electricaltreatment; 4) a PH regulat