Characterization of various reversed-phase columns using the linear free energy relationship: I. Evaluation based on retention factors

Nine prepacked narrow-pore and six wide-pore reversed-phase columns containing various ligands (C 18, C 8, C 4, CN) and obtained from different manufacturers were investigated. Retention factors of 34 solutes of widely different type were determined under isocratic conditions using an acetonitrile–water (30:70) mobile phase. Retention data were evaluated by principal component analysis (PCA) in order to compare column characteristics. Based on the same datasheet, stationary phase properties were compared in the frame of the linear free energy relationship (LFER) using solvation parameters of the solutes studied. The fitting coefficients of the LFER-based regression equations are characteristic of the individual stationary phases and represent the extent of the various molecular interactions contributing to the retention process. Column characterization furnished by PCA and LFER is discussed in detail.