Aim:Methodforthedeterninationoferythromycinethylsuccinale(EES)byionsuppressionchromatography(ISC)wasdevelopedandtheinfluencfactorsonISCwereinvestigated.Methods:AZorbaxSB-C18columnwasusedwith0.02mol.L^-1potassiumdihydrogenphosphate-acetonitrile(45:55)asmobilephase,ThepHandproportionofthemobilephaseshowedthegreatestinfluencesonretentionandselectivity.Therefore,thepHofmobilewasadjustedto6.8,thebhestacetonitrileproportionwas55%.Thecolumntemperaturewasmaintainedat(300±0.5)℃.AcetonitrilewasusedassolventforthesamplepreparationbecauseEESismorestableinit.Theflowratewas1.2mL.min^-1andUVdetectionwasperformedat210nm.Results:Underthesechromatographicconditions,themaincomponent(erythromycinAethylsuccinate)anditsrelatedsubstanceswereseparated.Thecalibrationcurveshowedgoodlinearityovertherangeof0.1-1.0mg.mL^-1,anditscorrelationcoefficientwas0.9998.Conclusion:Themethodisverysuitablefortheanalysisoferythromycinethylsuccinate.
