冬凌草甲素固体分散体的制备及溶出度测定

Preparation and dissolution rate determination of oridonin solid dispersion

目的冬凌草甲素水溶性差影响其生物利用度。文中以泊洛沙姆为载体制备冬凌草甲素固体分散体,提高其体外溶出度。方法以泊洛沙姆188为载体,采用溶剂法制备冬凌草甲素固体分散体,并采用差示扫描量热法和粉末X-射线衍射法鉴别冬凌草甲素在固体分散体中的状态,以高效液相色谱法测定原料药、物理混合物和固体分散体在不同p H溶出介质中的溶出度。结果冬凌草甲素分散在泊洛沙姆中,失去了原有的结晶结构,固体分散体的体外溶出研究表明：其浓度在1～25μg/m L范围内线性关系良好。进样精密度实验表明,低、中、高浓度的精密度分别为1.52%、0.85%、0.47%,RSD均〈2%。溶液稳定性实验测得RSD为1.1%,12h内稳定。回收率实验表明,低、中、高浓度冬凌草甲素的回收率分别为99.1%、100.5%、99.5%。原料药、物理混合物和冬凌草甲素固体分散体均以水、p H6.8磷酸盐缓冲液和p H1.2盐酸溶液为溶出介质的累积溶出度以冬凌草甲素固体分散体以作用60 min时最高,3种介质的累积溶出度分别为（92.6±4.2）%、（93.1±3.5）%、（94.4±2.9）%。结论成功制备以泊洛沙姆188为载体的冬凌草甲素固体分散体可提高其体外溶出度。

Objective Oridonin is a poorly water soluble drug with low bioavailability. The study aimed to prepared improve the dissolution rate of oridonin by preparation of oridonin solid dispersion with poloxamer. Methods The oridonin solid dispersion was prepared by dissolvent method with poloxamer188 as the carrier and determined by DSC and powder X-ray diffraction. The dissolution rates in different p H dissolution mediums of pure drug,physical mixture and solid dispersion were determined by HPLC method.Results Oridonin exists as an amorphous state in the solid dispersion. Compared with the pure drug and physical mixture,the oridonin solid dispersion was improved greatly without the p H influence on the drug release. The dissolution rate of oridonin solid dispersion in water,p H 6. 8 PBS and p H 1. 2 HCl were（ 92. 6 ± 4. 2） %,（ 93. 1 ± 3. 5） % and（ 94. 4 ± 2. 9） % respectively. Conclusion Taking inpoloxamer188 as the carrier,the oridonin solid dispersion has successfully developed its dissolution rate.