Analysis of ceftazidime and related compounds by micellar electrokinetic chromatography

A micellar electrokinetic chromatographic method for the separation and quantification of ceftazidime, its delta2-isomer and pyridine (two ceftazidime related impurities) was developed and validated. Optimised conditions were obtained using an electrolyte system consisting of 25 mM sodium tetraborate, at pH 9.2, and 75 mM sodium dodecylsulphate. A limit of detection of 0.2 microg ml(-1) and a limit of quantitation of 0.6 microg ml(-1) were estimated for pyridine and delta2-isomer: this means that levels of < 0.1% of pyridine and delta2-isomer in ceftazidime can be determined. Calibration curves for all analytes were linear over the studied ranges with correlation coefficients >0.999. Good reproducibility for migration times and corrected peak areas were achieved (RSD % 0.3 and 1.0, respectively). The results demonstrate that the method is reproducible, accurate and appropriate for ceftazidime assay in pharmaceutical samples.