Abstract: Objective: To optimize conditions for the preparation of propolis derived flavonoid (PF) liposome. Methods: PF liposomes were prepared by ethanol injection method. One-factor-at-a-time design was used to investigate the effects of five process parameters on encapsulation efficiency. Three main process parameters that influence encapsulation efficiency including lecithin/PF mass ratio, lecithin/cholesterol mass ratio and injection speed were optimized by response surface analysis based on a three-variable, three-level Box-Behnken experimental design. Results: The optimal conditions for preparing PF liposomes were determined as 9.6:1 of lecithin/PF mass ratio, 8.5:1 of lecithin/cholesterol mass ratio and 0.8 mL/min of injection speed. Conclusion: Under these conditions, the actual encapsulation efficiency of PF liposomes was 91.67%, which showed a relative error of 0.086% when compared with the predictive value.

Key words: response surface methodology, propolis derived flavonoid liposome, encapsulation efficiency, ethanol injection method, lecithin/PF mass ratio