Objective:To prepare doxorubicin-tetrandrine complex liposomes for technology study and quality control.In order to provide a new idea to reverse the tumor multidrug resistance in clinic.Methods:The formulations of doxorubicin-tetrandrine complex liposomes were optimized by three different kinds of methods.And the optimum formula was selected according to the entrapment efficiency.Re- sults:The complex liposomes were prepared by(NH4)2SO4-gradient method combined with pH gradient method according to optimum recipe.The optimum recipe of DOX-TET liposome was founded as DOX-TET/EPC of 1∶10

EPC/Ch of 3∶1

pH value of 7.6

incubation temperature of 50℃

(NH4)2SO4 concentration of 250 mmol/L.Under the formulation

DOX and TET were encapsulated 90.77%and 80.12%

respectively.Conclusion:The doxorubicin-tetrandrine complex liposomes have high entrapment efficiency with fine looking

which provides basis for the further studies.