Abstract
This study centered on creating and validating a UPLC-MS/MS assay that is both reliable and simple, making it suitable for measuring peiminine levels in the plasma of beagle dogs. The established method was then employed with the ultimate goal of elucidating the pharmacokinetic behavior of the compound. The Acquity UPLC BEH C18 chromatographic column was used for separating peiminine and camptothecin (internal standard, ISTD). A binary mobile phase consisting of acetonitrile and 0.1% formic acid in water was used for gradient elution at 0.4 mL/min. In the multireaction monitoring mode, peiminine and a triple quadrupole mass spectrometer with an electrospray ionization source were utilized to monitor peiminine and the ISTD, and detection was performed by monitoring the following transitions: m/z 430.28 ⟶ 412.25 for peiminine and m/z 349.03 ⟶ 305.09 for the ISTD. Results indicated that the accuracy was around 100%, with both interday precision and intraday (RSD) being less than 10.37%. Additionally, a linear response for peiminine was validated over the range of 1-200 ng/mL, with the LLOQ established at 1 ng/mL. In summary, this study perfectly combined the ultrahigh chromatographic separation ability with the ultrahigh sensitivity, selectivity, and structural analysis ability of mass spectrometry, achieving rapid (2 min), accurate, and ultrasensitive (LLOQ 1 ng/mL) analysis of peiminine in samples. Using the developed method, the pharmacokinetic profile of peiminine was successfully characterized in beagle dogs following oral administration.