[Pharmacokinetics of eight constituents in rat plasma after oral administration of Modified Xiaochaihu Granules for gastric ulcer based on UPLC-MS/MS].

ABSTRACT

An ultra-performance liquid chromatography-tandem mass spectrometric method (UPLC-MS/MS) was developed in this study to simultaneously determine the contents of eight effective constituents in rat plasma, including baicalin, wogonoside, baicalein, liquiritin, glycyrrhizic acid, berberine hydrochloride, saikosaponin a and saikosaponin d in plasma of gastric ulcer rats, and investigate the pharmacokinetics of Modified Xiaochaihu Granules. Chromatographic separation was conducted on Zorbax SB-C18 column (2.1 mm×100 mm, 1.8 µm) with acetonitrile -0.1% formic acid aqueous solution as the mobile phase for gradient elution, at a flow rate of 0.4 mL·min⁻¹ and column temperature of 40 °C. Detection was performed in the multiple reaction monitoring (MRM) mode with ESI ion source. All calibration curves showed good linearity (r>0.996) over a wide concentration range for all constituents. RSDs of intra-day and inter-day precision were all within 15% and the extraction recoveries of all the constituents were in the range of 81.92% to 104.8%. The time to peak (tmax) of these eight constituents was (2.69±2.02), (5.17±2.04), (0.25±0), (0.83±0.26), (0.92±0.20), (0.92±0.20), (0.58±0.20), and (0.083±0) h, respectively; the half-life (t1/2) of them was (7.85±0.34), (10.16±2.21), (6.79±0.21), (8.32±0.48), (11.05±1.78), (11.56±3.46), (15.30±1.84), and (5.54±1.91) h, respectively; the peak concentration (Cmax) of them was (55.02±1.67), (213.66±4.62), (62.61±0.69), (68.43±1.42), (62.22±0.39), (30.17±1.89), (61.79±4.81), and (38.02±1.75) µg·L⁻¹, respectively. This established method is simple and accurate with good repeatability and strong specificity, which could provide modern experimental basis for modified Xiaochaihu granules in clinical treatment of gastric ulcer.