Comparative study of four flavonoids in cultivated scutellariae in Ningxia

Objective To establish a HPLC method for simultaneous determination of baica1in,wogonoside,baicalein and wogonin in cultivated Scutellariae and to study the difference of four flavonoids in cultivated scutellariae in Ningxia.Methods A Platisil ODS(250 mm×4.6 mm,5 μm) column was used at 40 ℃.Methanol:acetonitrile:acetate-sodium acetate(PH4.5) was used as the mobile phase with gradient elution.The detection wave length was 278 nm.The flow rate was 1.0 ml·min-1.Results The linear ranges of baicalin,wogonoside,baicalein and wogonin were respectively 0.07-15.43 μg(r =0.9998),0.02-3.73 μg(r =1.0000),0.007-1.44 μg(r =0.9999) and 0.003-0.51 μg(r =1.0000).The average recoveries were respectively 97.5%,98.7%,98.0% and 95.5%.And RSD were respectively 2.9%,1.9%,2.7% and 1.3%.The ranges of the content of baica1in,wogonoside,baicalein and wogonin in cultivated Scutellariae were 14.59%-23.29% in Ningxia.Conclusion The total content of baica1in,wogonoside,baicalein and wogonin in different months and different years and different localities in Ningxia have some difference.This method is simple,accurate and reliable.It can be used for the quality control of Scutellariae.