[Simultaneous determination of six triterpenoid acids from Guizhi Fuling capsules by UPLC-MS/MS]

To establish a UPLC-MS/MS method for simultaneous determination of six triterpenoid constituents (pachymic acid, dehydropachymic acid, dehydrotumulosic acid, polyporenic acid C, dehydroeburicoic acid and dehydrotra metenolic acid) in Guizhi Fuling capsules (GFC). Chromatographic analysis was conducted on Agilent Porosheell 120 SB-C₁₈ column (4.6 mm×150 mm, 2.7 μm), with 0.1% formic acid aqueous solution-methanol as the mobile phase for gradient elution at a flow rate of 0.4 mL•min-1. The column temperature was 30 ℃ and the sample size was 5 μL. The samples were analyzed by tandem mass spectrometer with negative electrospray ionization (ESI) source, and monitored under a multiple reaction monitoring (MRM) mode, with the quantitative ion pairs m/z 527.8→465.5 (pachymic acid), m/z 525.6→465.6 (dehydropachymic acid), m/z 483.4→337.3 (dehydrotumulosic acid), m/z 481.5→419.5 (polyporenic acid C), m/z 467.4→337.1 (dehydroeburicoic acid), m/z 453.4→337.0 (dehydrotra metenolic acid). Six triterpenoid acids showed good linear relationships within the investigated concentration ranges (r> 0.996 8), with RSDs of precision less than 6.2%, and all RSDs of repeatability less than 5.9%. The average recovery rate was 97.90%, 100.2%, 99.60%, 101.7%, 102.6% and 103.0% respectively. The method was rapid, accurate, repeatable and could be used as a method for quantitative determination of triterpenoid acids in Chinese medicine prescriptions, providing a reference method for the quality control of Guizhi Fuling capsules and providing a reference for the content determination for Chinese medicine prescriptions containing Poria cocos.