Determination of Paeoniflorin in Tongjingning Capsules by RP-HPLC

OBJECTIVE To establish a method for determining the concentration of paeoniflorin in Tongjingning capsules by RP-HPLC. METHODS RP-HPLC was used. Chromatography conditions: Hypersil C18 column(250 mm×4.6 mm, 5 μm), the mobile phase consists of acetonitrile-0.1% phosphoric(15∶85), the flow rate was 1.0 mL·min^-1, the detective wavelength was set at 230 nm, and column temperature was 30 ℃. RESULTS The calibration curve was linear in the range of 0.256-1.536 μg for paeoniflorin(r=0.999 9). The average recovery of paeoniflorin was 99.46% and RSD was 0.56% (n=9). CONCLUSION The method is simple and accurate with good repeatability, which can be used for the quality control of Tongjingning capsules.