Dependence of Methylene Selectivity on the Composition of Hydro-Organic Eluentsfor Reversed-Phase Liquid Chromatographic Systems with Alkyl Bonded Phases

摘要

A theoretical treatment is presented which considers differences between thecomposition of the mobile phase and solvents that are incorporated into the bonded phase via preferential sorption. Equations are derived and used to analyze retention data for various homologs chromatographed under reversed-phase conditions using alkyl bonded phases and combinations of water-methanol, water-acetonitrile and water-tetrahydrofuran as mobile phases. In the case of water-methanol the surface phase and bulk mobile phase compositions are similar. However, significant differences in composition between the two phases are observed when binary combinations of water-acetonitrile and water-tetrahydrofuran are used as the eluents.