RESUMO
OBJECTIVE:To establish a method for the simultaneous determination of paeoniflorin,baicalin and imperatorin in Urticaria pill. METHODS:HPLC was performed on the column of Alltima C18 with mobile phase of methanol-water-Phosphoric ac-id(55∶45∶0.2,V/V/V)at a flow rate of 1.0 ml/min,the detection wavelength was 230 nm for paeoniflorin,280 nm for baicalin and 300 nm for imperatorin,column temperature was 30 ℃,and the volume injection was 10 μl. RESULTS:The linear range was 5.40-54.0 μg/ml for paeoniflorin(r=0.999 8),11.29-112.9 μg/ml for baicalin(r=0.999 7)and 24.95-249.5 μg/ml for imperatorin (r=0.999 9),respectively;the linit of quantitation were 5.4、11.2、30.0 ng,the lirnit of detection were 1.8、2.8、7.5 ng;RSDs of pre-cision, stability and reproducibility tests were lower than 2%;recoveries were 95.88%-98.33%(RSD=0.95%,n=6), 96.86%-99.96%(RSD=1.20%,n=6)and 98.07%-100.55%(RSD=0.92%,n=6),respectively. CONCLUSIONS:The method is simple and accurate with strong specificity and good reproducibility,and can be used for the simultaneous determination of paeoni-florin,baicalin and imperatorin in Urticaria pill.