Mexiletine hydrochloride and its potential impurity xylenol were determined by micelar electrokinetic chromatography in a 25 cm long capillary. The effect of parameters – temperature, electric field, concentration of analyzed compounds, type and composition of background electrolyte – on the separation of analytes and precision of analysis was studied. The advantage of the elaborated method is a very short time of analysis (2.3 min) at the sufficient level of precision and reliability of results.

        Key words: mexiletine hydrochloride – xylenol – separation – determination – micelar electrokinetic chromatography.