ABSTRACT
Objective: To optimize the preparation conditions of astragalus polysaccharide (APS) liposome. Methods: APS liposome was prepared by membrane distribution-micromembrane extruding method. L9(34) orthogonal test was adopted to optimize the preparation conditions which was designed with three factors of lecithin to drug ratio, lecithin to cholesterol ratio, and ultrasonic time, and two indexes of encapsulation efficiency and drug-loading rate. The encapsulation efficiency of APS liposome was assayed by Protamine method, the shape and particle size were observed by transmission electron microscope. Results: The optimized preparation conditions were as follows: the ratio of lecithin to drug was 10:1, the ratio of lecithin to cholesterol was 8:1, and ultrasonic time was 20 min. Conclusion: The APS liposome prepared under the optimized conditions has following advantages: high encapsulation efficiency and drug-loading rate, uniform shape and particle size, and good reproduction quality.