应用电导率-含水量曲线法研究广东王不留行提取物为模型药物的O/W型微乳

Application of conductivity-water content curve to research Guangdong Vaccaria segetalis extract as a model drug of O/W-type microemulsion

目的：建立广东王不留行提取物为模型药物的O/W型微乳处方筛选及制备成型的一种方法。方法：选取文献及本实验室15个处方空白微乳建立电导率-含水量曲线,同时与目测法进行对比研究,选取其中4个稳定的微乳处方,分别建立以广东王不留行提取物为模型药物的O/W型微乳的电导率-含水量曲线,进行其方法学考察及微乳质量评价。结果：O/W型空白及含药微乳成型的临界点均是电导率-含水量曲线的顶点,进一步验证其值显著高于目测法测定的临界值,目测法所测定的O/W型微乳临界值在双连续区域内,通过电导率-含水量曲线确定的空白及含药O/W型微乳方法学实验RSD〈1%,空白及含药微乳平均粒径均在10~100 nm之间。结论：电导率-含水量曲线法制备的O/W型微乳分布均匀、具备量化、准确、重复性好,应用于微乳处方筛选及制备工艺研究具有理论及实际可行性,能准确反应微乳的相行为及结构变化。

OBJECTIVE To establish a method to screen formula and prepare O/W microemulsion with Guangdong Vaccaria extract as model drug.METHODS Literatures and microemulsion of 15 blank prescriptions in our laboratory were selected to establish a conductivity-water content curve,and compared with ocular estimation method.Four stable microemulsion prescriptions were selected to respectively establish conductivity-water content curves of O/W microemulsions with Guangdong Vaccaria extract as model drug,and investigate the methodology and evaluate microemulsion quality.RESULTS Vertices of conductivity-water content curves are the critical points of O/W microemulsions.It was further confirmed that the value was significantly higher than the critical point determined by ocular estimation.Critical points of O/W microemulsions determined by ocular estimation were within the double row area.RSD values determined by conductivity-water content curve were less than 1% for blank and drug-containing O/W microemulsions,and the mean particle sizes were all in the range of 10-100 for blank and drugcontaining microemulsions.CONCLUSION O/W microemulsion prepared with conductivity-water content curve is uniformly distributed,with good quantitation,accuracy and repeatability.The method is theoretically and practically feasible to screen prescription and prepare microemulsion,and can accurately reflect the changes of phase behavior and structure of microemulsions.