Application of micellar electrokinetic chromatography to the determination of sultamicillin in oral pharmaceutical preparations

A micellar electrokinetic capillary electrophoretic method for determination of sultamicillin in Unasyn oral preparations—tablets and suspension—was evaluated. Phosphate–borate buffer at pH 7.0 containing 1.0% sodium dodecylsulfate was used as a mobile phase. The elaborated method ensures separation of sultamicillin from p-toluenesulfonic acid and the impurities, ampicillin, sulbactam and penicillamine. The method was validated for specificity, reproducibility, precision, accuracy and assay linearity (in a concentration range of sultamicillin of 0.05—1.5 mg/ml). Statistical analysis by Student’s t-test showed no significant differences between the results obtained by micellar electrokinetic chromatography and HPLC, tcalculated 0.519 for suspension assays and 0.284 for tablets assays were smaller then ttabulated.