Application of liposome encapsulation technique to improve anti-carcinoma effect of resveratrol

Aim: The promising anti-tumor effect of resveratrol (RES) has aroused much interest in recent years, but its clinical application was seriously hindered due to its poor solubility in water. The aim of this study was to improve the water solubility of RES by liposome encapsulation technique for effective tumor treatment. Methods: This study develops two liposomal formulations to solubilize RES by reverse-phase evaporation method with or without poly(ethylene glycol-2000)-grafted distearolyl phosphatidylethanolamine (DSPE-PEG(2000)). The effect of different formulation factors on the encapsulation efficiency (EE) and the particle sizes were investigated. These factors included the mass ratio of drug to soybean phosphatidylcholine (drug/SPC), the mass ratio of cholesterol to soybean phosphatidylcholine (chol/SPC), the volume ratio of water phase/organic phase and the microfluidization process. The drug release studies were performed in various media, simulating the desired application conditions. The cytotoxicity study was carried out by MTT assay on HeLa and Hep G2 cell lines. Results: The RES EE of 95% was obtained when using drug/SPC (1: 40 mass ratio), Chol/SPC (1: 10 mass ratio), water phase/oil phase (1: 2 volume ratio), microfluidization process (entrance pressure 6 kpa, two times of cycle time). The addition of DSPE-PEG(2000) into the formulation showed little effect on the formation and properties of RES liposome. The release of RES was pH-independent. RES liposomes and PEG-modified liposomes performed significant inhibition effects on both cells growth due to the solubilized RES. Conclusion: RES can be effectively loaded into liposomes and its anti-cancer effect was evidently improved by the application of liposome encapsulation technique.