Determination and pharmacokinetic study of skimmin by UHPLC-MS/MS in rat plasma

Skimmin, a major active ingredient derived from Hydrangea paniculata, has been considered to possess various pharmacological activities, including renoprotective activity, anti-inflammatory, anti-cancer, and antiamoebic properties. However, no investigation has reported the quantification and pharmacokinetics of skimmin in biomatrices. In the present study, we established and validated an ultra-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for the estimation of skimmin in rat plasma, which was successfully applied to explore the oral and intravenous pharmacokinetics of skimmin. All plasma samples were obtained following blood collection from the rat' tail vein and prepared using the protein precipitation method with acetonitrile. Separation of the analyte and internal standard (IS) magnoflorine was achieved by a reversed phase T3 column. The mobile phase consisted of water containing 0.1 % formic acid and acetonitrile with a gradient elution program. The analytical run time was 4 min with a flow rate of 0.3 mL/min. Detection was carried out on a triple quadrupole tandem mass spectrometer equipped with electrospray ionization (ESI).Multiple reaction monitoring transitions were performed at m/z of 325.34 → 163.00 and 342.24 → 57.98 for skimmin and IS, respectively. The method demonstrated good linearity in the range of 2-2000 ng/mL and was validated by US FDA bioanalytical guidelines. A pharmacokinetic study of skimmin was then successfully conducted using the validated method. Hence, the absolute bioavailability of skimmin was approximately 25.08 % with rapid absorption and elimination. This study will be beneficial in better understanding the pharmacological properties and the further development of skimmin.