Determination of Paeoniflorin and Baicalin in Biejiajian Pill by HPLC

Objective An HPLC method was established for the determination of paeoniflorin and baicalin in biejiajian pill.Methods Paeoniflorin was separated on a C18 column with gradient elution using the mobile phase of acetonitrile 0.05 mol·L-1 potassium dihydrogen phosphate solution,and detected at the wavelength of 230 nm.Baicalin was separated on the same column with methanol-water-phosphoric acid(42:58:0.5) as mobile phase,and detected at the wavelength of 280 nm.Results The calibration curves were linear in the ranges of 0.076 6-1.532 8 μg and 0.061 4-0.770 4 μg,the average recovery was 98.0% and 96.5%(n=6),with RSDs of 0.7% and 1.1%,respectively.Conclusion Two analytical methods were established to determine the two active ingredients for quality control of the biejiajian Pill.