| As one kind of new drug carrier, emulsomes were studied more in recent years, it is a composition comprising dehydrated lipid particles,and which is surrounded by at least one phospholipid bilayer. Particles contain a hydrophobic core, as in standard oil-in-water emulsions, which is surrounded and stabilized by one or more layers or envelopes of phospholipid molecules, as in liposomes. Emulsomes, having the characteristics of both liposomes and emulsions, provide the advantages of high hydrophobic drug loading in the internal solid lipid core and the ability to encapsulate water-soluble medicaments in the aqueous compartments of surrounding phospholipid layers. Since emulsomes are biomembrane-like vesicles, they were mainly licked up by the reticulo-endothelial system when enter into the human body, thus activate the immunity function, and change the in-vivo distribution of the enveloped drugs, making the drug mainly distributed at the liver, the spleen, the lung and the marrow organizes, thus enhances the treatment index, reduces the therapeutic dosage and the toxicity of the drug. Therefore, emulsome acts as a drug delivery system with great potential.Silybin (Silibinin or silybin, SIL) derived from the herb. Silibinin is the flavonoid compounds of lignin, with a wide range of pharmacological effects. Silibinin to stabilize liver cell membrane, protect liver cell enzyme system, clear the liver cells of reactive oxygen free radicals, from the resistance to increase liver detoxification capacity of liver cells in long-term exposure to avoid the poison, taking the liver toxicity of drugs, smoking, drinking such circumstances suffered injury, is recognized worldwide as the precise effect of liver injury and regeneration medicine. Studies have shown that silibinin also has a good treatment of hyperlipemia, eliminating free radicals, anti-hepatic lipid peroxidation, anti-ischemia-reperfusion injury. Because of high efficacy, low toxicity, silibinin from discovery has been cause for concern. This paper examines the composition and preparation process prescriptions on the SIL encapsulation rate of emulsome, and its nature and Pharmacy intravenous pharmacokinetics in rats were studied.SIL emulsomes were prepared by thin film dispersion(TFD), after screened by orthogonal experimental design, the optimized formula was drugs: phospholipids =1:16(weight ration), trilaurin:Lipid=1: 8 (weight ratio),cholesterol: phospholipids =4: 13 (weight ratio), Tween-80: phospholipids =1:1(weight ratio), the pH is7.4. The content determination was conducted by HPLC. Glucan gel column chromatography was used to determine the encapsulation efficiency of SIL emulsomes. Through the transmission electron microscopy, the form of emulsome was observed, with Zetasizer 3000HS laser particle size analytical instrument, the particle size and zeta potential of the particles was measured. Results showed that the emulsome was intact spherical or oval-shaped ball vesicle, encapsulation efficiency was over 80%, the mean particle diameter was 364.1nm, and Zeta potential was -34.1mV.After comparing the phenomena of test tubes with negative and positive control, SIL emulsomes were found not to cause hemolysis in-vitro. Emulsomes were preserved at room temperature (about 25℃) and 4℃for fifteen days respectively ,determine the encapsulation efficiency, leakage rates were 5.6%,2.7% separately, the results showed that the better storage for emulsomes temperature is 4℃. Release behavior in vitro of SIL emulsomes was studied and showed sustained-release feature.The pharmacokinetic characteristics of a single dose intravenous injection of SIL emulsomes in rats were investigated compared with that of SIL solution, and the data were calculated by means of 3p97. According to compartment-model fitting results, SIL emulsomes and SIL solution were both fitted with two compartment-model with a weight of 1. T1/2βof SIL emulsomes and solution was 35.98 min min and 16.06 min respectively, and the clearance rate was 0.16 ml·min-1 and 0.29 ml·min-1. As the results calculated according to statistical moment theory:AUC of SIL emulsomes and solution was 26.03μg·min·ml-1 and 11.75μg·min·ml-1 respectively, and MRT was 51.51min and 20.59min. This denotes emulsomes, compared with the solution, can extend circulation time of drugs in vivo.
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