HPLC-MS/MS Determination of Puerarin and Daidzein in Puerarin Root

HPLC-MS/MS was applied to the determination of pueratin and daidzein in puerarin root. The sample was extracted with ethanol, and the extract obtained was filtrated, made up to 100 mL with ethanol and used for HPLC-MS/MS determination, using Waters Xterra MS C18 column (150 mm×3.9 mm, 5 μm) as chromatographic column, and a mixture of acetonitrile and 50 mmol·L-1 ammonium acetate solution (mixed in the ratio of 40 to 60 by vol.) as mobile phase. Positive electrospray ionization and multiple reaction monitoring mode were used in the detection. Linear relationships between values of peak area and mass concentration were obtained in ranges of 0.050-0.50 mg·L-1 (for pueratin) and 5.0-50 mg·L-1 (for daidzein), with same detection limits (3S/N) of 5 μg·L-1. Tests for recovery were performed by standard addition method at 3 concentration levels of 0.1,1.0, 10.0 mg·L-1; results of recovery of pueratin and daidzein found were 96.6% and 97.4% respectively.