Stationary phase effects in reversed-phase liquid chromatography

Abstract

In addition to dispersive and non-specific interactions at the surface of the adsorbent in reversed-phase liquid chromatography, specific effects also exist. The latter are mainly due to unreacted silanol groups and to the extracted layer of organic solvent. These specific effects are investigated by comparing capacity factors and liquid—liquid extraction constants, K LLE. When chemically identical LLE and chromatographic systems are compared, plots of log k′ vs. log K LLE allow one to estimate specific stationary phase effects. The rôle of the solute and the solvent composition is discussed.