Simultaneous determination of five compounds of fried Radix Paeoniae Alba extract in beagle dogs plasma by Ultra Performance Liquid Chromatography Tandem Mass Spectrometry and its application in a pharmacokinetic study

Abstract In this present study, we developed a reliable and simple ultra‐performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS) assay for the simultaneous quantification of paeoniflorin, albiflorin, oxypaeoniflorin, benzoylpaeoniflorin and isomaltopaeoniflorin in beagle dog plasma. We also analyzed the pharmacokinetics of those components after oral administration of fried Radix Paeoniae Alba (FRPA) in beagle dogs. Plasma samples were processed by protein precipitation with methanol. Chromatographic separation was performed with a Waters HSS‐T3 C 18 column (100 × 2.1 mm, 1.8 μm, kept at 40°C) using multiple reaction monitoring mode. A gradient elution procedure was used with solvent A (0.02% formic acid–water) and solvent B (0.02% formic acid–acetonitrile) as mobile phases. Method validation was performed as US Food and Drug Administration guidelines, and the results met the acceptance criteria. The method we establish in this experiment was successfully applied to the pharmacokinetic study after oral administration of FRPA extract to beagle dogs.