Objective: To optimize formulation of Saussurea involucrate transfersomes. Method: S. involucrata transfersomes was prepared by combining injection technique with high shear scattered method

effects of three independent variables including the concentration of phospholipid

ratio of drug-lipid and volume ratio of oil phase-water phase were investigated

with entrapment efficiency and drug loading of chlorogenic acid and rutin

mean particle size and normalized value as evaluation indexes

central composite design/response surface method was used to optimized formulation

test results were fitted by multiple linear and binomial nonlinear equations

and optimum formulation was selected by response surface method. Result: Binomial was optimum model to describe between indexes and factors.According to optimal preparation conditions of S. involucrate transfersomes

entrapment efficiency of chlorogenic acid and rutin were 83.44%

70.69 respectively

drug loading were 4.65%

3.94% respectively

and average particle size with 154.6 nm

there was small deviations between theoretical value and measured value

this model had good predictability. Conclusion: Central composite design/response surface method was a feasible and convenient method to optimize prescription of S. involucrate transfersomes.