Characterization of different RP-HPLC columns by a gradient elution technique

The literature contains no unified testing procedure for evaluation and characterization of reversed-phase (RP) columns of different pore sizes (surface area) and containing different types of ligand. In our laboratory a testing procedure has been developed using gradient elution under standardized conditions independent of column dimensions and applicable to both narrow-pore and wide-pore columns. Six wide-pore and four narrow-pore columns were investigated and compared. The test solutes were selected to cover a wide range of chemical properties. The evaluation and characterization of the columns was performed on the basis of k a pp retention factors. Principal components analysis (PCA) was performed to reveal similarities and differences among the columns and test substances. The factors obtained characterize the columns according to the extent of various interactions such as hydrophobicity, HB (hydrogen bond)-donor acidity and HB-acceptor basicity.