[Simultaneous assay of four isoflavonoids in Astragali Radix by QAMS]

Based on the complexity of the chemical constitutions in traditional Chinese medicines (TCMs), multi-components analysis used for the quality control of TCMs is more scientific and reasonable. However, routine quality control of TCMs by multi-components analysis is limited for the shortage of various chemical reference substances. Herein, the method of quantitative analysis of multi-components by single marker (QAMS) was validated and used to simultaneously determine calycosin-7-O-beta-D-glucopyranoside, ononin, calycosin, formononetin in Radix Astragali. Using formononetin as the internal reference substance, the relative correction factors (RCFs) of the other three isoflavonoids were calculated by HPLC-DAD with good reproducibility in different instruments and chromatographic columns. The other three isoflavonoids in 34 batches of samples were simultaneously calculated according to their RCFs. The results of QAMS method were not significantly different from that of external standard method (RSD < 3.5%). It is accurate and feasible to evaluate the quality of Radix Astragali by QAMS.