[Determination of puerarin in three traditional Chinese patent medicines by high performance liquid chromatography]

A simple and accurate reversed-phase high performance liquid chromatographic method to determine puerarin in three traditional Chinese patent medicines, namely "Xiao'er qingganling" tablet, "Buchang xinnaoxintong" capsulae and "Ganmao qingre" granule is described. "Xiao'er qingganling" tablet and "Buchang xinnaoxintong" capsulae were extracted with methanol in an ultrasonic bath and "Ganmao qingre" granule was extracted with water and ethanol. After being centrifuged and filtered, the samples were separated on an ODS column with a mobile phase of 100 mmol/L ammonium acetate buffer (pH 5.0)-methanol(75:25, volume ratio). The flow rate was 0.8 mL/min, and the detection wavelength was 250 nm. The calibration curve was linear in the range of 2 mg/L-20 mg/L puerarin (r = 0.9999). The average recoveries were 99.0%, 93.4% and 97.5% for "Xiao'er qingganling" tablet, "Buchang xinnaoxintong" capsulae, "Ganmao qingre" granule respectively. The average contents of puerarin in the medicines were 3.48 mg/g, 1.08 mg/g and 1.52 mg/g (sucrose), and the relative standard deviations were 1.9%, 1.4% and 1.4% respectively.