RESUMO
Objective: To develop an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for simultaneous determination of six components (indirubin, peimine, peiminine, ginkalide A, ginkalide B, and ginkalide C) in Baikening Granules. Methods: Preparing the samples solution by Soxhlet's extraction using methanol-chloroform as solvent, and multiple reaction monitoring (MRM) with a polarity-switching electrospray ionization (ESI) source between positive and negative modes was used for the quantification of indirubin, two peimisines, and three bilobalides. The detection was performed on an Inertsutain C18 column (75 mm × 3.0 mm, 2 μm) using a mobile phase consisted of methanol-acetonitrile and 2 mmol/L ammonium acetate water solution with gradient elution lasting 6 min. Results: All of the analytes showed good linearity (r ≥ 0.995 8) in the tested ranges. The precision, repeatability, and stability of the method were good for the six components. The average recoveries were in the range of 96.5%-105.1% with relative standard deviations (RSD) ≤ 4.2%. Conclusion: The new established polarity-switching LC-MS-MS method has been proven to be highly sensitive and effective in evaluating the quality of Baikening Granules, and peimine, peiminine, ginkalide A, ginkalide B, and ginkalide C are quantified in this drug for the first time.