Study on isoflavonoids in Radix Astragali

Objective:To corroborate the structures of the four isoflavonoids(calycosin-7-O-β-D-glucopyranoside,formononetin-7-O-β-D-glucopyranoside,calycosin and formononetin)in Radix Astragali by LC-MS/MS method and compare their relative contents in Radix Astragali from different sources.Methods:HPLC-DAD analysis was performed with a Waters 2695 high performance liquid chromatogram,equipped with a Waters 2996 diode array detector.LC-MS/MS analysis was performed with an Agilent G6300 serious LC-MSD Trap.The separation was carried out by using an Alltima C18 column(250 mm×4.6 mm,5 μm)with a gradient mobile phase of acetonitrile-water solution,which column temperature,flow rate and detector wavelength were set at 35 ℃,0.8 mL·min-1 and 260 nm.The analytes were eluted within 90 min.Results:The LC-MS/MS technique could be applied to the qualitative analysis of the chemical component in the same type.There was difference in the content of four isoflavonoids from Radix Astragali of different sources.Conclusion:The developed method here is useful to control the quality of Radix Astragali,and distinguish Radix Astragali from the other samples by the simultaneously qualitative analysis of the four isoflavonoids.