Determination of Ginsenosides and Epimedium Flavonoids in Rats Bile by HPLC-UV/ELSD

An HPLC-UV/ELSD method was established for the simultaneous determination of ginsenosides (Rg_1,Re),icariin and epimedins(A,B,C) in rat bile after intravenous administration of Jiweiling lyophilized powder. A C_(18) column was used with acetonitrile-water as mobile phase by gradient elution at the detection wavelength of 220 nm.An evaporative light scattering detector(ELSD) was used at drift tube temperature of 80℃and gas pressure of 25 psi.The calibration curves of ginsenosides(Rg_1,Re),icariin and epimedins(A,B,C) were linear in the concentration ranges of 11.64-698.1,8.59-515.4,2.70-323.4,1.53-183.6,1.04-499.2 and 1.37-878.4μg/ml,respectively.The average extraction recoveries were 89.53%-99.54%.The intra- and inter-day RSDs were less than 9.28%and the relative errors were within the range of-9.85%-5.10%.