Simultaneous Determination of Three Coumarins in Rat Plasma by HPLC-MS/MS for Pharmacokinetic Studies Following Oral Administration of Chimonanthi Radix Extract
Abstract Chimonanthi Radix (CR) is widely used in the treatment of influenza in China. Extensive studies revealed that the major bioactive constituents of CR were coumarins. However, pharmacokinetic study of coumarins in CR has not been fully studied. The purpose of this study was to establish a convenient and effective high-performance liquid chromatography–tandem mass spectrometry method that was used to simultaneously determine scopoletin, scopolin and isofraxidin in rat plasma after oral administration of CR extract using xanthotoxin as the internal standard. The chromatographic separation was carried out on a COSMOCORE C18 column (100 × 2 mm, 2.6 μm), using gradient elution with the mobile phase consisting of 0.1% formic acid (A) and acetonitrile (B). Three coumarins and IS were quantified by positive ion electrospray ionization in multiple reaction monitoring mode. The method was fully validated in terms of specificity, accuracy, precision (intra- and inter-day), matrix effect, recovery as well as the stability of the analytes under various conditions. The results could provide further research foundation for anti-influenza mechanism of three coumarins in CR.