DETERMINATION OF CHLOROGENIC ACID, BAICALIN AND FORSYTHIN IN SHUANGHUANGLIAN PREPARATIONS BY HPLC-DAD

High performance liquid chromatography coupled with diode array detection (HPLC-DAD) was developed for the simultaneous determination of three bioactive components - chlorogenic acid, baicalin and forsythin - in traditional Chinese medicinal Shuanghuanglian preparations. The analytes were extracted successfully using 80% aqueous methanol for 15 min in an ultrasonic bath. The optical chromatographic separation conditions were performed on a Finnigan Surveyor HPLC system with an Agilent Zorbax ODS C18 (4.6x150 mm, particle size 5 ì é ) at 30 oC using a gradient elution program with a mixture of acetonitrile and 0.2% phosphoric acid (v/v) as mobile phase within 25 min. Method validation results were obtained through the generation of calibration curves with the mixed standard solutions and a standard addition method, regression equations revealed linear relationships (correlation coefficients 0.9965-0.9985) between the peak area and concentration of the three analytes. The average recoveries were 90-106% (n= 6) with standard deviation below 3.37%. The developed HPLC assay was specific and could be readily utilized for comprehensive evaluation of Shuanghuanglian preparations.