Capillary zone electrophoresis as a potential technique for the simultaneous determination of sulfadoxine and pyrimethamine in tablet formulations

► A simple and rapid capillary zone electrophoresis method has been developed for the simultaneous determination of pyrimethamine and sulfadoxine in tablet formulations. ► The results have shown a good agreement with the HPLC method described of the United States Pharmacopoeia. ► Main advantages of the CZE method are short analysis time and low running cost. A novel, simple and rapid capillary zone electrophoresis method with UV detection has been developed for the simultaneous determination of pyrimethamine and sulfadoxine in tablet formulations. The compounds are separated in 6 min in a fused silica capillary, 30 cm long (20 cm to detector) × 50 μm using a 100 mM phosphate buffer pH 7.2 as background electrolyte, a 330 V cm −1 electric field and a detection wavelength of 214 nm. Analysis of different tablet formulations has shown a good agreement with the liquid chromatography method described in the United States Pharmacopoeia. Main advantages of the CZE method are the rapid set-up of instrumentation and capillary equilibration, short analysis time and low running cost.