Simultaneous determination of 10 active components in traditional Chinese medicine “YIGONG” capsule by RP-HPLC–DAD

A simple, reliable and accurate method for the simultaneous separation and determination of 10 active components (psoralen, isopsoralen, emodin, oleanolic acid, stachydrine hydrochloride, ammonium glycyrrhizinate, glycyrrhizinate, schizandrol, imperatorin and isoimperatorin) in traditional Chinese medicine “YIGONG” capsule was developed using reverse phase high-performance liquid chromatography (RP-HPLC) coupled with diode array detection. The chromatographic separation was performed on a Eurospher C18 column (250 mm × 4.6 mm i.d. with 5.0 μm particle size) with a acetonitrile–water gradient containing 0.5% (v/v) aqueous phosphoric acid as mobile phase. Two detection wavelengths (210 and 250 nm) were utilized for the quantitative analysis due to the different UV spectra of these components. Good linear behaviors over the investigated concentration ranges were observed with the values of R2 higher than 0.999 for all the analytes. The recoveries, measured at three concentration levels, varied from 95.0 to 105.3%. The validated method was successfully applied to the simultaneously determination of these active components in “YIGONG” capsule from different production batches.