A capillary electrophoresis assay for the analysis of sertaconazole has been developed and validated. The influence of buffer concentration, buffer pH, organic modifier, capillary temperature, applied voltage and injection time was systemically investigated in a fused silica capillary (i.d. 50 mu m, total length 80.5 cm and effective length 72.0 cm). Optimum results were obtained with a 20 mM phosphate buffer (pH 4.0) containing 40% acetonitrile, capillary temperature 30 degrees C, applied voltage 30 kV and 3 s hydrodynamic injection at 50 mbar. The detection wavelength was set to 205 nm. Verapamil was used as internal standard. The method showed good selectivity, repeatability, linearity and sensitivity according to the evaluation of the validation parameters. The method was applied to the determination of sertaconazole in pharmaceutical cream formulations. (c) 2004 Elsevier B.V. All rights reserved.