title: High-performance liquid chromatographic assay of erythromycin and its esters using electrochemical detection.
abstract: A high-performance liquid chromatographic analysis of erythromycin and its esters in plasma, urine and saliva is presented. A diethyl ether extract of sample was chromatographed on a reversed-phase column and components of the column effluent were monitored by electrochemical detection at +0.9 V (vs. Ag/AgCl). The method sensitivity limit was 10 ng with inter-day coefficients of variation from 3.2 to 10.3%. In order to assess precisely the relative concentrations of erythromycin esters (ethylsuccinate or estolate) and their active by-product erythromycin base, it is necessary to adopt measures preventing their continuous hydrolysis in biological fluids and during sample preparation.
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004355:Drug Stability; D004563:Electrochemistry; D004917:Erythromycin / Q000031:analogs & derivatives / Q000032:analysis* / Q000097:blood / Q000652:urine; D004918:Erythromycin Estolate / Q000032:analysis / Q000097:blood / Q000652:urine; D015643:Erythromycin Ethylsuccinate; D006207:Half-Life; D006801:Humans; D012463:Saliva / Q000032:analysis
chemical_list: D015643:Erythromycin Ethylsuccinate; D004917:Erythromycin; D004918:Erythromycin Estolate