[Determination of active components in silymarin by UPLC-ESIMS]

A UPLC-ESIMS method was developed for simultaneous analysis of seven major bioactive flavonolignans in silymarin including silychristins A(1) and B(2), silydianin(3), silybins A(4) and B(5), and isosilybins A(6) and B(7). In this study, the seven major active flavonolignans including the diastereomers 1/2, 4/5, and 6/7 were completely separated using UPLC with an ACQUITY UPLC C18 column and MeOH-water (formic acid) mobile phase system. The collision-induced dissociation (CID) MS/MS spectra of these flavonolignans were studied systematically using ESI-MS. The results with the present methodology showed that UPLC-MS/MS can be used for general screening of active natural products from plant extracts and for the specific quality control of silymarin.