Method Development and Validation for the Direct Determination of Cefepime in Human Serum by Micellar Electrokinetic Capillary Chromatography

A method for determining the concentration of cefepime, a cephem anti-microbial agent, by direct serum injection using micellar electrokinetic capillary chromatography is developed and its validation of the assay is studied. A borate buffer (100 mM; pH 8.0) containing sodium dodecyl sulfate (80 mM) is used as a run buffer. Ultraviolet detection is carried out at 260 nm. The migration time of cefepime is about 5.2 min. The limit of detection is 0.5 mg/l (S/N=3). The RSD's of intra-day and inter-day precisions are 1.57-4.08 % (6.8-94.2 mg/l) and 1.47-2.75 % (10.2-81.5 mg/l), respectively, and the recovery rate is 94-108%. 13 other cephem anti-microbial agents are measured under the analytical conditions of this method and the results show that cefatrizine, whose migration time coincides with that of cefepime, interferes with the determination of cefepime. This method is characterized by the ability of allowing analysis by the direct injection of serum samples of micro-quantities into the capillary.