Determination of Fargesin in Rat Plasma by UPLC-MS/MS and its Pharmacokinetics Application

Fargesin has a strong medicinal value, and has a variety of biological activities and pharmacological functions, such as lowering blood pressure, anti-inflammation. In this study, we used UPLCMS/MS to detect fargesin in rat plasma, and investigated its pharmacokinetics in rats. Byakangelicol was utilized as an internal standard, and acetonitrile precipitation method was used to process the plasma samples. Chromatographic separation was achieved using a UPLC BEH column (2.1 x 50 mm, 1.7 mu m) with a gradient acetonitrile-water mobile phase (containing 0.1 % formic acid). Flow rate was set at 0.4 mL/min. Electrospray ionization (ESI) tandem mass spectrometry in multiple reaction monitoring (MRM) mode with positive ionization was applied. The results indicated that within the range of 1-1000 ng/mL, linearity of fargesin in rat plasma was acceptable (r > 0.995), and the lowest limit of quantification (LLOQ) was 1 ng/mL. Intra-day and inter-day precision relative standard deviation (RSD) of fargesin in plasma were lower than 14%. Accuracy range was between 88.6 and 109.5 %, average recovery was higher than 92.7 %, and matrix effect was between 92.4 and 96.5 %. The analysis method was sensitive and fast with suitable selectivity, and was successfully applied in the pharmacokinetics of fargesin in rats after oral and intravenous administration. The absolute bioavailability of the fargesin was 4.7 % in rats.