RESUMO
Objective To study the preparation and properties of alkalized shikonin liposome.Methods Alkalized shikonin was purified from extracts of radix lithospermi with an alkali solution and acid formulation, and then the alkalized shikonin liposome was prepared by ethanol injection.The morphology, particle size and Zeta potential were determined, and the encapsulation efficiency and the in vitro release property were investigated.The content of L-shikonin was also measured by High Performance Liquid Chromatography.Results Alkalized shikonin liposome presented even sphere and normal distribution with particle size of 104.2nm.The Zeta potential was-14.8mV.L-shikonin was linear in the range of 5-50mg/L with the correlation coefficient 0.999 9.The encapsulation efficiency was 43.67％.The final release rate was 65.82％.Conclusion Alkalized shikonin liposome was prepared successfully with good entrapment efficiency and in vitro release property.
RESUMO
OBJECTIVE: To prepare amino-modified ordered mesoporous silica (NH2-OMS) as a drug carrier and test the loading and release properties of poorly water soluble drug carried by it. METHODS: OMS was first prepared using cetyltrimethyl ammonium bromide as the template and then modified by 3-aminopropyl trimethoxy silane to prepare NH2-OMS. N2 adsorption-desorption, X-ray diffraction and thermogravimetric analysis were used to characterize the NH2-OMS. Quercetin was loaded onto NH2-OMS in order to explore the drug loading properties of NH2-OMS. RESULTS: The drug loading and entrapment efficiency of quercetin-NH2-OMS were about 21.0% and 58.2%, respectively, when the concentration of quercetin was 4 mmol·L-1, the reaction time was 24 h and the temperature was set at 50°C. The in vitro release test demonstrated that quercetin-NH2-OMS could form supersaturated solution in simulated intestinal fluid and gastric fluid at concentrations of 13-fold and 27-fold of the thermodynamic solubility of quercetion. CONCLUSION: NH2-OMS, as the carrier for quercetin, can significantly increase its water solubility and release rate in intestinal and gastric fluids.