Quantification of Pectolinarin in Rat Plasma Using UPLC‐MS/MS and Its Pharmacokinetic Analysis

ABSTRACT Pectolinarin is a flavonoid compound known for its wound‐healing properties, including anti‐inflammatory and antibacterial effects. In this study, we employed UPLC‐MS/MS to quantify pectolinarin in rat plasma and investigate its pharmacokinetics. Plasma samples were processed using an acetonitrile precipitation method. Chromatographic separation was performed on a UPLC BEH column with a gradient mobile phase of acetonitrile‐water (containing 0.1% formic acid). Detection was carried out using electrospray ionization (ESI) tandem mass spectrometry in multiple reaction monitoring (MRM) mode with positive ionization, targeting transitions of m / z 623.3 → 315.3 for pectolinarin and m / z 370.5 → 125.0 for the IS. The results demonstrated that pectolinarin exhibited acceptable linearity in rat plasma within the concentration range of 1.2 to 2300 ng/mL ( r > 0.995). The intraday and interday precision, expressed as relative standard deviation (RSD), was below 9.2%. Accuracy ranged from 97.3% to 108.3%, with average recovery exceeding 94.7%. The matrix effect was between 97.8% and 105.3%. The method was successfully applied to evaluate the pharmacokinetics of pectolinarin in rats following both oral and intravenous administration. The absolute bioavailability of pectolinarin in rats was determined to be 0.28%.