Alpha Tocopherol Loaded in Liposome: Preparation, Optimization, Characterization and Sperm Motility Protection

Background: Alpha-tocopherol is a potent antioxidant involved in sperm protection particularly during cryopreservation. However, its poor solubility limits the optimal protection in aqueous solutions. Objective: The aim of this study was to enhance the solubility of α-tocopherol by the use of liposomes. Methods: The experimental approach included loading vitamin E in liposomes prepared by ethanol injection method and the optimization carried out by an experimental design. The optimum solution was characterized by high performance liquid chromatography and scanning electron microscope. Finely, the impact on sperm motility protection was studied by the freezing technic of bovine sperm. Results: The optimum solution was obtained when using 10.9 mg/ml of phospholipids, 1.7 mg/ml of cholesterol and 2 mg/ml of vitamin E. The liposome size was 99.86 nm, providing 78.47% of loaded efficiency. The results showed a significant positive impact on sperm motility after hours of preservation. Conclusion: In conclusion, the current results showed the interest of liposome preparation as an alternative to enhance vitamin E solubility and to protect spermatozoa during cryopreservation.