Determination of Oleanolic and Ursolic Acids in Fructus Corni by Capillary Zone Electrophoresis

Capillary zone electrophoresis (CZE) with high frequency conductivity detection was applied to the determination of oleanolic and ursolic acids in Fructus corni.An uncoated elastic fused quartz capillary column (55 cm×75 μm,effective length 50 cm) was used and efficient separation was achieved by using the buffer mixture (containing 1.2 mmol·L-1 triethylaminehydrochloric acid solution and 0.08 mmol·L-1 β-cyclodextrin solution with its acidity adjusted to pH 10.60) as moving solution,and the separation voltage at 12.5 kV.The sample was introduced hydrostatically at a height of 20 cm for 10 s.“Buluofen” was used as internal standard.Linear relationships between values of ratio of peak area of the analyte to peak area of the internal standard and mass concentration of the analyte were obtained in the ranges of 4.1-114.8 mg·L-1 (for oleanolic acid) and 4.3-120.4 mg·L-1 (for ursolic acid).Recovery was tested by standard addition method,values of average recovery of 96.0% were found for the both analytes.The proposed method was used for determination of oleanolic acid and ursolic acid in samples of Fructus corni,giving values of RSD′s (n=6) of 2.03%,2.29%,respectively.