The Study On The Separation Of β-Elemene And The Preparation Of Its Liposomes

β-elemene is a new anticancer drug which had been used to treat patients. The purification ofβ-elemene and development its drug delivery system are the way to eliminate the side effect. The separation ofβ-elemene and the preparation of its liposomes were studied in this thesis.Batch vacuum rectification was applied to separate 80.5%β-elemene mixture from citionella oil. Vacuum pressure was controlled at 2660Pa, and reflux was 5:1. Through twice rectification, theβ-elemene content was up to 90.6%. However, the content increased slightly through 3 times rectification.Silica gel column chromatography was applied to separate 90.6%β-elemene mixture with loading 1/100 (mixture/silica gel, w/w) mixture and eluted acetic acetate (EAc): methanol (1:1). The result showed that main body mixture after elution solvent volatilized was content 95%β-elemene. When silver nitrate (SN) silica gel was adopted as chromatography medium and petroleum ester (PE)-EAc (10:1~1:1) as gradual elution,β-elemene content was more than 98.0%. The isotherm adsorption ofβ-elemene at the silica gel surface is not conformed to Langmuir monomolecular adsorption.and this might be related to three unsaturated double bonds inβ-elemene molecular. The isotherm adsorption ofβ-elemene at the SN silica gel surface is like Langmuir monomolecular adsorption, and the ultraviolet spectrum ofβ-elemene-Ag+ compound coordinated byσ-πbonds is different from that ofβ-elemene.Theβ-elemene liposomes were prepared by the thin film hydration (TFH), the reverse-phase evaporation (REV) and REV plus high pressure extrusion, respectively. The particle diameter ofβ-elemene liposome was measured by dynamic light scattering (DLS), and the configuration was observed by electron transparent microscope (TEM). The freeβ-elemene was extracted with petroleum ester (PE), and the entrapment efficiency ofβ-elemene was analyzed indirectly by gas phase chromatography (GC). The stability was determing by centrifuge at 1000g. The results show that the ratio of soybean PC: cholesterol:β-elemene=400: 40.8: 54 (w/w) is better to form liposome and that the buffer solution affectsβ-elemene's forming and storage stability. The liposomes preparated by REV plus high pressure extrusion are small unilamellar vesicles (SUVs) (77.4nm) and their entrapment efficiency are more than 99%.