CORRELATION BETWEEN CHEMICAL-STRUCTURE OF NONCONGENERIC SOLUTES AND THEIR RETENTION ON POLYBUTADIENE-COATED ALUMINA

The high-performance liquid chromatographic capacity factors extrapolated to pure water were determined on a polybutadiene-coated alumina (PBCA) stationary phase for a selected set of non-congeneric solutes. The structures of the test solutes were characterized by means of calculated hydrophobicity parameters and several non-empirical molecular descriptors, including topological indices, information content indices and quantum chemical indices. Unique properties of PBCA for the chromatographic determination of the hydrophobicity of diverse compounds were demonstrated. Quantitative structure-retention relationship (QSRR) studies employing non-empirical structural descriptors showed that the mechanism of retention on PBCA was similar to that on ODS phases. For a quantitative description of retention, structural parameters reflecting the bulkiness of solutes (positive input) and their polarity (negative input) predominated. Principal component analysis of structural descriptors most often used in QSRR studies allowed the extraction of two principal factors that describe retention more adequately than the individual descriptors studied. Informative values of non-empirical structural indices for the evaluation of retention were compared. © 1990.