Determination of chlorogenic acid and baicalin in Yinhuang capsules by HPLC

OBJECTIVE To establish a RP HPLC method for determination of chlorogenic acid and baicalin in Yinhuang capsules. METHOD The Nova pakC 18 (250mm×4.6mm,10mm) column was used .The mobile phase for analysis chlorogenic acid was consisted of acetonitile 0.4% phosphoric acid (13∶87),the detection wavelength was at 327nm. The mobile phase for baicalin was consisted of methanol 0.4%phosphoric acid(50∶50), the detection wavelength was at 280nm. Both of the flow rates were 1.0mL·min -1 .RESULTS The calibration curve of chlorogenic acid was in linear over the range of 0.2301～1.6107μg,and regression equation was U=2595.8Х+1.2964 ( r = 0.999 9 ).The average recovery was 99.58%( RSD =1.10%, n =5), RSD of reproduction was 0.46%. The calibration curve of baicalin was in linear over the range of 0.2453～1.4718μg,and regression equation was U=3045.3Х-1.3333 (r=0.9999).The average recovery was 99.88%( RSD =0.89%, n =5). RSD of reproduction was 0.56%.CONCLUSION The method is simple ,quick ,sensitive ,accurate ,reproducible and can be use to control the quality of Yinhuang capsules.