Determination of Shanzhiside Methylester in Rat Plasma by Uplc-Ms/Ms and Its Application to a Pharmacokinetic Study

Introduction: In this study, we used UPLC-MS/MS to detect shanzhiside methylester in rat plasma, and investigated its pharmacokinetics in rats. Materials and Methods: Diazepam was utilized as an internal standard (IS), and acetonitrile precipitation method was used to process the plasma samples. Chromatographic separation was achieved using a UPLC BEH C18 column using mobile phase of methanol-0.1 % formic acid with gradient elution. Electrospray ionization (ESI) tandem mass spectrometry in multiple reaction monitoring (MRM) mode with positive ionization was applied. Results: The results indicated that within the range of 5-4000 ng/mL, linearity of shanzhiside methylester in rat plasma was acceptable (r>0.995), and the lower limit of quantification (LLOQ) was 5 ng/mL. Intra-day and inter-day precision RSD of shanzhiside methylester in rat plasma were lower than 14%. Accuracy range was between 87.3 % and 109.1 %, and matrix effect was between 99.2% and 106.3%. Conclusion: The method was successfully applied in the pharmacokinetics of shanzhiside methylester in rats after intravenous administration.