RESUMO
OBJECTIVE:To establish a method for the simultaneous determination of chlorogenic acid,paeoniflorin,ferulic ac-id,berberine hydrochloride and baicalin in Lianqiao baidu pill. METHODS:HPLC was performed on the column of Agilent Eclipse XDB-C18 with mobile phase of 0.5% phosphoric acid(triethylamine adjusted to pH 3.0)-methanol(gradient elution)at a flow rate of 1.0 ml/min,the column temperature was 30 ℃,the detection wavelength was 230 nm(for paeoniflorin and berberine hydrochlo-ride),324 nm(for chlorogenic acid and ferulic acid)and 278 nm(for baicalin),and the injection volume was 5 μl. RESULTS:The linear range was 1.884-30.144 μg/ml for chlorogenic acid(r=0.999 9),0.392-6.272 μg/ml for paeoniflorin(r=0.999 7), 0.102-1.632 μg/ml for ferulic acid(r=0.999 7),1.326-21.216 μg/ml for berberine hydrochloride(r=0.999 8) and 1.95-31.2 μg/ml for baicalin(r=0.999 9),respectively;RSDs of precision,stability and reproducibility tests were lower than 2.0%;recoveries were 99.58%-102.47%(RSD=0.93%,n=9),99.21%-102.18%(RSD=0.90%,n=9),98.28%-101.23%(RSD=0.86%,n=9), 99.66%-101.84%(RSD=0.82%,n=9)and 99.18%-101.05%(RSD=0.62%,n=9). CONCLUSIONS:The method is accurate,re-liable,simple and fast,and can be used for the simultaneous determination of chlorogenic acid,paeoniflorin,ferulic acid,berber-ine hydrochloride and baicalin Lianqiao baidu pill.