Abstract
A novel micellar electrokinetic capillary chromatographic (MEKC) method was developed for the simultaneous determination of ombitasvir (OMB), paritaprevir (PAR), ritonavir (RIT) and dasabuvir (DAS). The technique was based on the separation of all of the selected drugs in a deactivated fused silica capillary with a background electrolyte solution (BGE) composed of 25 mM phosphate buffer with 30 mM sodium dodecyl sulphate (SDS) (the pH of the aqueous phase was adjusted to 8) mixed with ethanol in a ratio of 65:35 (v/v). The capillary and sample temperature was maintained at 24 °C, and the detection was performed at 239 nm. The electrophoresis was performed by applying high voltage (30 kV) to the capillary. The strategy was completely approved according to ICH rules over the concentration range of 2.5 to 100 µg/mL for all of the drugs. The limits of detection were 0.16 µg/mL (PAR, DAS, and OMB) and 0.625 μg/mL (RIT), while the quantitation limits were 0.31 μg/mL (PAR, DAS, and OMB) and 1.250 μg/mL (RIT). The proposed MEKC method was successfully applied for the quantitation of the four drugs in tablets with high precision and accuracy. For the first time, these drugs were simultaneously determined by capillary electrophoresis.