Pharmacokinetic study of seven bioactive components of Xiaoyan Lidan Formula in cholestatic and control rats using...

A rapid, sensitive, and reliable ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method has been developed to simultaneously determine the major bioactive components of Xiaoyan Lidan Formula (XYLDF) in rat plasma, using sulfamethoxazole as the internal standard (IS). The seven major bioactive components are andrographolide, dehydroandrographolide, enmein, 1-methoxicabony-β-carboline, 4,5-dimethoxy-canthin-6-one, 4-methoxy-5-hydroxy-canthin-6-one, and 1-hydroxymethyl-β-carboline. After pretreating by protein precipitation with methanol, separation was performed on a UPLC C18 column using gradient elution with a mobile phase consisting of acetonitrile and 0.1% formic acid at a flowing rate of 0.7 mL/min. Detection was performed on TSQ Quantum mass spectrometry set at the positive/negative ionization and multiple reaction monitoring (MRM) mode. The intra- and inter-day precision were less than 9.8%, whereas the intra- and inter-day accuracy were within ± 13.4%. The method was validated and applied to compare the pharmacokinetic profiles of the analytes in serum of Alpha-naphthylisothiocyanate (ANIT)-induced cholestasis and control rats after oral administration of XYLDF. The results showed remarkable differences in pharmacokinetic properties of the analytes between cholestatic (model) and control groups, thereby providing essential scientific information for better understanding of mechanism of XYLDF and a reference for its clinical applications.