Determination of ebrotidine and its metabolites by capillary electrophoresis with UV and mass spectrometry detection

This study describes the application of capillary electrophoresis (CE) to t he analysis of ebrotidine and its metabolites as an alternative analytical technique to liquid chromatography. Comparison between UV-diode array spect roscopy and mass spectrometry (MS) using an ion-trap system with electrospr ay ionization as detection systems has been performed. The quality paramete rs of the UV detection method were established obtaining linear calibration curves over the range studied (8-200 mg ml(-1)), limits of detection betwe en 3.4 and 4.3 mu g ml(-1), and run-to-run and day-to-day precision lower t han 14%. For these compounds the protonated species [M+H](+) and, in some c ases, sodium adducts were observed in the MS spectra. Using MS coupled to C E, limits of detection were between 0.5 and 2.6 mu g ml(-1). (C) 2000 Elsev ier Science B.V. All rights reserved.