CAPILLARY ELECTROPHORETIC DETERMINATION OF HUANGQIN GLUCOSIDE AND CHLOROGENIC ACID IN QINKAILING ORAL LIQUOR AND YINHUANG TABLETS

Influential factors (including the pH and concentration of buffer solution,the working voltage and the times of sample-introduction) of the capillary electrophoretic determination of baicalin and chlorogenic acid in “Qinkailing oral liquid” and “Yinhuang” tablets were studied and optimized.Linear relationships between peak heights and concentrations for baicalin and chlorogenic acid were obtained in the ranges of 0.06-1.20 g·L-1 and 0.02-0.50 g·L-1 respectively.RSD′s found for baicalin were 1.60% (based on migration time) and 2.63% (based on peak height),and for chlorogenic acid were 1.48% (based on migration time) and 2.65% (based on peak height).Detection limit (S/N=3) obtained for baicalin was 0.020 g·L-1 and for chlorogenic acid was 0.004 g·L-1.In the application of the proposed method to the analysis of two drug samples,RSD′s of less than 4% were obtained.Recovery test was made by standard addition method based on “Yinhuang” tablet sample,and values of 97.6% (for baicalin) and 97.3% (for chlorogenic acid) were obtained.