Study on the related substances of Salvianolic acid A by HPLC-MS/MS

OBJECTIVE Our aim of this study was to analyze and deduce the structures of some trace substances in Salvianolic acid A material.METHODS A method employing on-line high performance liquid chromatography coupled with tandem mass spectrometry was selected to obtain their pseudo-molecule ions and characteristic fragments.Further,their UV spectra will give more structural information.Chromatographic analysis was performed on an Aglient XB-C18(250mm×5mm,5μm) column eluted by a mixed mobile-phase of acetonitrile and 0.2% acetic acid in water at 1.0mL·min-1.A DAD and a mass spectrometer(LCQ Advantage) were coupled with this column as detectors.The MS instrument was operated in negative mode.Then full scan and MS2 analyses were employed to gain the abundant structure information of Salvianolic acid A and its related substances.RESULTS Three trace compounds whose content was more than 0.1% were registered.CONCLUSION Based on their MS/MS and UV data,two of them were preferred to be cis-trans isomers of Salvianolic acid A.And the third compound was tentatively identified as Salvianolic acid C.