Novel and simple nonaqueous capillary electrophoresis separation and determination bioactive triterpenes in Chinese herbs

Three bioactive triterpenes ursolic acid, oleanolic acid and 2α,3β,24-trihydroxy-urs-12-en-28-oic acid were simultaneously separated by nonaqueous capillary electrophoresis (NACE) with methanol:acetonitrile (65:35 v/v) mixture containing 90 mm trishydroxymethylaminomethane (Tris) at an applied voltage of +25 kV and a hydrodynamic injection of 5 s. The effect of solvent composition, electrolyte nature and concentration on the electrophoretic behavior of the analytes were systematically studied. Separations were carried out in a fused-silica capillary tube with UV detection at 214 nm. Good separation and correlation coefficients were obtained. Meanwhile, the method was applied to separation and determination the three components in six Chinese herbs extraction. It is concluded that this method could be used for speedy and accurate qualitative and quantitative analysis of bioactive triterpenes in Chinese herbs.