Simultaneous determination and pharmacokinetic study of gambogic acid and gambogenic acid in rat plasma after oral administration of Garcinia hanburyi extracts by LC‐MS/MS

Gambogic acid and gambogenic acid are two major bioactive components of Garcinia hanburyi , and play a pivotal role in biologic activity. In this study, a specific and sensitive liquid chromatography–tandem mass spectrometry was developed and validated for simultaneous determination of gambogic acid and gambogenic acid in rat plasma. Chromatographic separation was achieved on a C 18 column using an isocratic elution with methanol–10 m m ammonium acetate buffer–acetic acid (90:10:0.1, v/v/v) as the mobile phase. The detection was performed on a triple–quadrupole tandem mass spectrometer equipped with electrospray positive ionization using multiple reaction monitoring modes. The transitions monitored were m/z 629.3 [M + H] + → 573.2 for gambogic acid, m/z 631.2 [M + H] + → 507.2 for gambogenic acid and m/z 444.2 [M + NH 4 ] + → 83.1 for IS. Linear calibration curves were obtained in the concentration range of 2.00–1000 ng/mL for gambogic acid and 0.500–250 ng/mL for gambogenic acid. The lower limits of quantification of gambogic acid and gambogenic acid in rat plasma were 2.00 and 0.500 ng/mL, respectively. The intra‐ and inter‐day precision (RSD) values were <11.7% and accuracy (RE) was −10.6–12.4% at three QC levels for both analytes. The assay was successfully applied to evaluate pharmacokinetics behavior in rats after oral administration of Garcinia hanburyi extracts. Copyright © 2014 John Wiley & Sons, Ltd.