TEMPERATURE-DEPENDENCE OF RETENTION IN REVERSED-PHASE ION-INTERACTION CHROMATOGRAPHY

The dependence of retention on temperature in reversed-phase ion-interaction chromatography is investigated. 5mM octylammonium o-phosphate in aqueous solution is used as the interaction reagent, and retention of analytes characterized by different chemical properties is considered in the temperature range of 25-55°C. Variation of the thermodynamic parameters of enthalpy and entropy for the transfer process of the solute from the mobile to the stationary phase are evaluated. The results indicate that the retention process proceeds in the temperature range investigated through only a single mechanism and that similar retention mechanisms characterize all the analytes studied, independent of their chemical structure. © 1995, Oxford University Press.