Identification and determination of major constituents in a traditional Chinese medicine compound recipe Xiongdankaiming tablet using HPLC-PDA/ESI-MS n and HPLC-UV/ELSD

Xiongdankaiming tablet (XDKMT), a well-known compound in traditional Chinese medicine, is widely used for the treatment of acute iridocyclitis and primary open-angle glaucoma. In this paper, accurate and reliable methods were developed for the identification of 20 constituents using high-performance liquid chromatography with photo-diode array and electron spray ionization-mass spectrometry (HPLC-PDA/ESI-MS(n)), and determination of nine of the constituents (chlorogenic acid, gentiopicroside, isochlorogenic acid B, diosmetin-7-O-β-d-glucopyranoside, apigenin, diosmetin, tauroursodeoxycholic acid, acacetin, and taurochenodeoxycholic acid) was developed using HPLC with ultraviolet absorption detector and evaporative light scattering detector (HPLC-UV/ELSD) for the first time. The best results were obtained on a Zorbax SB-C18 column with gradient elution using water (0.1% formic acid) (A) and methanol (0.1% formic acid) (B) at a flow rate of 0.7 ml/min. Tauroursodeoxycholic acid and taurochenodeoxycholic acid, owing to their low UV absorption, were detected by ELSD. The other seven compounds were analyzed by HPLC-UV with variable wavelengths. The calibration curves of all nine constituents showed good linear regression (R(2)>0.9996) within the linearity ranges. The limits of detection and quantification were in the ranges of 0.0460-9.90 μg/ml and 0.115-24.8 μg/ml, respectively. The accuracy, in terms of recovery, varied from 95.3% to 104.9% with relative standard deviations (RSDs) less than 4.4%. Precision (with the intra- and inter-day variations less than 4.4%) was also suitable for its intended use. The developed method was successfully applied for the analysis of major components in XDKMT, which provides an appropriate method for the quality control of XDKMT.