RP-HPLC determination of four compounds of flavonoids in Houttuynia cordata Thunb.

Objective :To determine the contents of rutin,hyperin,quercitrin and quercetin in Houttuynia cordata Thunb.by HPLC.Methods:An external standard method by HPLC with Kromasil-C_(18) column(250 mm×4.6 mm,10 μm)as fixed phase,H_2O-CH_3CN-H_3PO_4(400:100:0.2)as one mobile phase,which was changed to another mobile phase CH_3CN-CH_3OH-H_2O-H_3PO_4(375:75:50:0.1)at 30 min was adopted.The detection wavelength was 350 nm and the flow rate was 1.0 mL·min~(-1).Results:Rutin,hyperin,quercitrin and quercetin were well separated by this method.Linearities of rutin,hyperin,quercitrin and quercetin were good in ranges of 0.055-0.550μg(r= 0.9979),0.248-2.480 μg(r=0.9977),0.520-5.200μg(r=0.9998),0.062-0.623 μg(r=0.9961) ,re- spectively.The average recoveries were 103.5%,104.0%,102.6% ,103.7% and RSD of the values of repeatabili- ty were 3.9% ,0.8%,1.0%,1.6% ,respectively.Conclusion:The method validation data indicates that the meth- od is reliable and it can be used for quality control of Houttuynia cordata Thunb.and its preparations.