[Preparation and characterization of niosomes of Semen Strychni alkaloids extract].

OBJECTIVE: To prepare a noisome formulation of Semen Strychni alkaloids extract with high encapsulation efficiency. METHOD: S. Strychni alkaloids were encapsulated into niosomes by pH gradient loading method. The factors influencing on the encapsulation efficiency were investigated, and formulation and preparation process of niosomes were optimised and validated. RESULT: When the drug to lipid weight ratio was under 1: 10, pH gradient in buffer solution of citric acid at 50 degrees C was more than 4.0, the niosomes (mean diameter 179.2 nm and Zeta potential -25.41 mV) were formed with encapsulation efficiency of over 86.9%. CONCLUSION: The pH gradient loading method was reliable for preparing niosomes of Semen Strychni alkaloids extract.