DETERMINATION OF EPHEDRINE, GASTRODIN, AND LIGUSTRAZIN IN SPIKED RAT PLASMA BY CAPILLARY MICELLAR ELECTROKINETIC CHROMATOGRAPHY

A simple and rapid capillary micellar electrokinetic chromatography (MEKC) method was developed for the separation and determination of ephedrine, gastrodin and ligustrazin in tetraborate buffer by direct UV detection at 200 nm. The effect of separation voltage, the concentration of sodium dodecyl sulfate (SDS) and the buffer pH value on separation was optimized and the following conditions was selected: 20 kV voltage, 15 mM SDS in 50 mM tetraborate buffer at pH = 9.50. The detection limit of these substances was below 1.0 µg/mL, respectively, and the linear range spanned two orders of magnitude. This method was applied to the detection of ephedrine, gastrodin and ligustrazin spiked in rat plasma.