RESUMO
Abstract A capillary electrophoresis method was developed for the first time and optimized for the determination of paracetamol, pseudoephedrine, dextromethorphan, chlorpheniramine, 4-aminophenol and ephedrine in tablet formulation. Optimum electrophoretic conditions were achieved by using a background electrolyte of 75 mmol L-1 sodium borate buffer at pH 8.0, a capillary temperature of 30°C, a separation voltage of 30 kV and a pressure injection of the sample at 50 mbar for 10 s. Calibration graphs showed a good linearity with a coefficient of determination (R2) of at least 0.999 for all compounds. Intraday and interday precision (expressed as relative standard deviation (RSD) %) were lower than 1.39% for capillary electrophoresis method. The developed method was demonstrated to be simple and rapid for the determination of paracetamol, pseudoephedrine, dextromethorphan, chlorpheniramine, 4-aminophenol and ephedrine in tablet formulation providing recoveries in the range between 99.62 and 100.57% for all analytes.