Abstract: The objective of this study was to optimize the preparation of tea polyphenol liposomes using response surface methodology (RSM). Using one-factor-at-a-time design, four process conditions including tea polyphenol/phosphatidylcholine (TP/PC) mass ratio, cholesterol/phosphatidylcholine (CH/PC) mass ratio, VE/phosphatidylcholine (VE/PC) mass ratio and ethanol volume were identified as main variables that influence encapsulation efficiency. The four process conditions were optimized by response surface analysis based on a four-variable, three-level Box-Behnken experimental design. The results showed that the optimal TP/PC, CH/PC and VE/PC mass ratio were 81:300, 58:300 and 16.7:300, respectively and that 4.5 mL of ethanol was needed. Under these conditions, the encapsulation efficiency of TP liposomes was 78.10%. The TP liposomes obtained showed uniform morphology and irregular oval shape and were distributed in the range of 400－1000 nm.

Key words: tea polyphenol, liposome, response surface methodology, encapsulation efficiency, process conditions