In this study, analyses were carried out on a fused-silica capillary (i.d. 50.0 mu m, total length 48.5 cm, and effective length 40.0 cm) in normal mode by applying a voltage of 20 kV. Sample injections were made in hydrodynamic mode over 7 s under a pressure of 50 mbar. The capillary temperature was set at 35 degrees C and the detection was performed at a wavelength of 205 nm. The background electrolyte was 40 mM citrate buffer at pH 6.0 and the internal standard was labetalol hydrochloride. The total analysis time was shorter than 5 minutes. The method was validated according to the International Conference on Harmonization (ICH) guidelines, and the method was found to be linear, precise, accurate, specific, robust, and rugged. The linearity range was found to be 1.0-60.0 mu g ml(-1) and the limit of detection and quantitation were 0.5 and 1.0 mu g ml(-1), respectively. The developed method was proposed for quality-control laboratories.