The Synthesis And Application In Drug Carrier Of Liposomes

Glyceryl dilaurate was synthesized through two step reactions by sodium Laurate and epichlorohydrin with the help of phase translational catalyst cetyl trimethy] ammonium bromide. When the molar ratio of sodium laurate and epichlorohydrin 1 to 2 , cetyl trimethyl ammonium bromide 0.5 % ,reaction temperature 110℃ and reaction time 2h the yield of glycidyl laurate was 86%; When the molar ratio of glycidyl laurate and lauric acid 1 to 2, reaction temperature 110℃ ,reaction time 1.5h the highest yield of glyceryl dilaurate was 63%.Vc liposomes were prepared by the supersound method with glyceryl dilaurate as synthetic materials. The structure of liposome was determined by the biologic microscope , the Transmission Electronic Microscope and the Scanning Electronic Microscopy. The result showed that the shapes of Vc liposomes were round and well dispersed .The concentration on entrapment efficiency was investigated. Single factor tests and orthogonal tests on the ratio of material and cholesterol, the supersound time, the water temperature, and the ratio of material and drug were carried out for optimization. The optimal conditions were found to be the supersound time 15min ,the water temperature 0℃, the material and cholesterol ratio 2 tol, the material and drug ratio 10 to 1.The study on the stability showed that Vc liposomes should be kept under the condition of low temperature. The effects of quality of liposome and temperature on the leakage rate were investigated. Within 10h ,the leakage rate were 37.5%, 45.3%, 48.3% when the temperature were 20℃, 30℃, 40℃ respectively.The leakage rate were 37.5% , 35.4% , 34.3% when the entrapment efficiency were 33.2%, 21.0%, 10.3% respectively.The release rate of Vc liposomes had beeninvestigated and the results showed that the release rate of Vc from liposomes was 68.5% after 12h.