Simultaneous quantification of chlorogenic acid and taurocholic acid in human plasma by LC-MS/MS and its application to a pharmacokinetic study after oral administration of Shuanghua Baihe tablets

An LC-MS/MS method was developed and validated for the simultaneous quantification of chlorogenic acid（CGA） and taurocholic acid（TCA） in human plasma using hydrochlorothiazide as the internal standard. The chromatographic separation was achieved on a Hedera ODS-2 column with a gradient elution using 10 mmol·L-1 of ammonium acetate buffer solution containing 0.5% of formic acid- acetonitrile as mobile phase at a flow rate of 300 μL·min-1. The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring in negative ESI mode. The method was fully validated over the concentration ranges of 0.1–10 ng·m L-1 for CGA and 2–150 ng·m L-1 for TCA. It was successfully applied to a pharmacokinetic study of CGA and TCA in healthy Chinese volunteers after oral administration of Shuanghua Baihe tablets（SBTs）. In the single-dose study, the maximum plasma concentration(Cmax), time to reach Cmax(Tmax) and elimination half-life(t1/2) of CGA were（0.763 8 ± 0.542 0） ng·m L-1,（1.0 ± 0.5） h, and（1.3 ± 0.6） h, respectively. In the multiple-dose study, the Cmax, Tmax and t1/2 of CGA were（0.663 7 ± 0.583 3） ng·m L-1,（1.1 ± 0.5） h, and（1.4 ± 0.7） h, respectively. For TCA, no significant characteristic increasing plasma TCA concentration-time curve was found in the volunteers after oral administration of SBTs, indicating its complicated process in vivo as an endogenous ingredient.