电导率-含水量曲线法测定O/W型微乳的稳定性

Determination of the stability of O / W-type microemulsion by conductivity-water content curve method

目的采用电导率-含水量曲线法测定空白及中药挥发油为模型药物的O/W型微乳的稳定性。方法分别建立空白及以肉桂油为模型药物的O/W型微乳电导率-含水量曲线;制备临界含水量的空白及含药O/W型微乳,测定其在常温放置24 h、35℃恒温、75%相对湿度下离心及超声处理后的稳定性。结果电导率-含水量曲线的顶点均为O/W型微乳成型的临界点;所制备的临界含水量的空白及含药微乳均符合要求,经常温、恒温恒湿、离心及超声等不同条件处理后的电导率基本无变化。结论所用方法准确、重复性好,能准确反应微乳的相行为及结构变化。

OBJECTIVE To establish a method to detect the stability of O / W- type microemulsion which use blank or traditional Chinese medicine volatile oil as model drug by conductivity- water content curve method. METHODS The O / W- type microemulsion conductivity- water content curve of blank and cinnamon oil were established. The blank and contained O / W microemulsion critical moisture content were prepared,and the stability was determined of the critical moisture content of blank and contained microemulsion after stored in normal temperature for 24 h,35 ℃ RH 75% humidity,centrifugal and ultrasonic treatment. RESULTS The conductivity- water content curve vertices were critical points of O / W type microemulsion forming. The critical moisture content of blank and contained microemulsion after stored in constant temperature,humidity,centrifugal and ultrasonic treatments were not significantly different. CONCLUSION The method is accurate and reproducible,and can reflect the phase behavior of microemulsion and the change of structure.