A UPLC-MS/MS Method for Simultaneous Determination of Six Bioactive Compounds in Rat Plasma, and its Application to Pharmacokinetic Studies of Naoshuantong Granule in Rats

Background: It is urgently needed to clarify the pharmacokinetic mechanism for the multibioactive constituents in Traditional Chinese Medicines for its clinical applications. A rapid, sensitive and reliable ultra-performance liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous determination of Danshensu, Ferulic acid, Astragaloside IV, Naringin, Neohesperidin and Puerarin after oral administration of Naoshuantong Granule using Carbamazepine as internal standard (IS). Methods: The plasma samples were pretreated by liquid-liquid extraction method using ethyl acetate after acidification, and separated on a Waters ACQUITY UPLC® BEH C18 column (50×2.1 mm, i.d., 1.7 µm) by gradient elution with a mobile phase composing of water (containing 0.1% formic acid) and acetonitrile at a flow rate of 0.2 mL/min. Multiple reaction monitoring (MRM) mode with both positive and negative ion mode was operated using an electrospray ionization (ESI) to detect the six compounds. Result: All calibration curves showed good linearity (r>0.99) over a wide concentration range. The intra- and inter-day precision (RSD%) was below 8.4% and the accuracy (RE%) ranged from 91.1% to 107.5%. The extraction recoveries of the six analytes and IS in the plasma were more than 77.9% and no severe matrix effect was observed. Conclusion: The fully validated method was successfully applied to the pharmacokinetics of Naoshuantong Granule.