Development and Validation of Nonaqueous Capillary Electrophoresis Method for Simultaneous Estimation of Icariin, Icariside II, and Epimedin K in Epimedium Leaves

This paper describes a novel nonaqueous capillary electrophoresis method for the separation and determination of Icariin, Icariside II, and Epimedin K in Epimedium leaves. Three flavonoids were extracted by ultrasonication with EtOH-H2O (70:30) followed by a HP 20 resin column cleanup procedure. The optimized electrophoretic conditions were obtained with the running solution of 8mM borate MeCN/H2O (60:40, v/v) (pH 11.40), separation voltage of +20kV and detection wavelength of 270nm. The limits of quantification ranged from 0.24 to 0.84mg/kg (signal/noise=3) for three flavonoids. Three flavonoids in 10 Epimedium leaves were successfully measured and evaluated.