Simultaneous Determination of Geniposide and Baicalin in Niuhuang Qingwei Pills by RP-HPLC

Objective:To establish a method for simultaneously determining geniposide and baicalin in Niuhuangqingwei pills.Method:A double wavelength RP-HPLC method was developed.The analysis was performed on a Hibar C18 column(4.6 mm×150 mm,5 μm) with gradient elution using 0.2% phosphoric acid(A) and acetonitrile(B) in the order of 0-9.00 min 15%B and 9.00-10.00 min 15%-25%B,after 10.00 min,25%B,the flow rate was 1.0 mL·min-1.Geniposide and baicalin were detected at 240 nm and 278 nm respectively.The column temperature was at 30 ℃.Result:The calibration curves of geniposide and baicalin showed good linearity in the ranges of 0.16-0.80 μg and 0.69-1.61 μg.The average recoveries were 98.62% and 96.93% with RSD of 1.97% and 2.12% respectively.Conclusion:The method is simple,accurate and reproducible for simultaneous determination of geniposide and baicalin in Niuhuang Qingwei pills.