Assay of Erythromycin from Human Serum by High Performance Liquid Chromatography with Electrochemical Detection

Abstract

Abstract A sensitive and selective method has been developed for the determination of serum concentrations of erythromycin A by high performance liquid chromatography with electrochemical detection. Erythromycin was extracted from alkalinized serum samples with methyl t-butyl ether. After evaporation of the ether, the samples were reconstituted in acetonitrile/ammonium acetate and washed with hexane. Aliquots were injected onto a Sepralyte diphenyl column. The mobile phase consists of acetonitrile/sodium perchlorate/ammonium acetate/methanol under isocratic conditions. Eluted peaks were detected by dual coulometric electrodes operated in the oxidative screen mode. The recovery of erythromycin from serum was 84%. Assay limit of quantification was 0.05 μg/ml serum, and dynamic linear range was 0.05–1.5 μg/ml. This method was used to quantitate both erythromycin and its gastric degradation products from human serum. Additionally, other macrolide antibiotics could be quantified by electrochemical detection. A...