Analysis of different β-lactams antibiotics in pharmaceutical preparations using micellar electrokinetic capillary chromatography

The potential of micellar electrokinetic capillary chromatography (MEKC) for analyzing nine β-lactams antibiotics (cloxacillin, dicloxacillin, oxacillin, penicillin G, penicillin V, ampicillin, nafcillin, piperacillin, amoxicillin) in different pharmaceutical preparations, have been demonstrated. An experimental design strategy has been applied to optimize the main variables: pH and buffer concentration, concentration of the micellar medium, separation voltage and capillary temperature. Borate buffer (26 mM) at pH 8.5 containing 100 mM sodium dodecyl sulphate (SDS) was used as the background electrolyte. The method was validated. Linearity, limit of detection and quantitation and precision were established for each compound. The analysis of some of the β-lactams in Orbenin capsules, Britapen tables and in Veterin–Micipen injectable, all used in human and veterinary medicine, have demonstrated the applicability of these technique for quality control in the pharmaceutical industry.