Ion-Exchange Chromatography

Abstract

Ion exchangers consist of an insoluble framework (matrix) containing covalently bonded dissociable functional groups at accessible sites. These are either sulfonic acid groups or, less importantly, carboxyl groups in the case of cation exchangers, and tertiary amino or quaternary ammonium groups for anion exchangers. Substances that are at least partially ionic in strongly polar eluents can be separated by this method. Separation is based on the affinity differences of ions toward their counter-ions in the ion exchange matrix and those dissolved in the eluent.