Deuterium nuclear magnetic resonance spectroscopy as a probe for reversed-phase liquid chromatographic bonded phase solvation: methanol and acetonitrile mobile phase components

Abstract

Using the inversion-recovery method, deuterium longitudinal relaxation times, ( T 1), of [ 2H 4]methanol and [ 2H 3]acetonitrile in enriched methanol—water and acetonitrile—water mobile phases were measured for the neat binary mixtures, and for the mixtures in contact with two different monomeric C 18 reversed-phase stationary phases. Changes in the deuterium relaxation times for the organic modifiers in contact with the stationary phase compared to those observed in neat solution give a qualitative understanding of the degree of association of the organic components with the stationary phase. Both bulk solution microstructure and stationary phase C 18 bonding density play important roles in determining bonded phase solvation.