LINEAR SOLVATION ENERGY RELATIONSHIP STUDY OF RETENTION IN MICELLAR LIQUID CHROMATOGRAPHY ON A C18 COLUMN USING SODIUM DODECYL SULFATE AND CETYLTRIMETHYLAMMONIUM BROMIDE MOBILE PHASES WITH ALCOHOL MODIFIERS

Abstract

The fundamental chemical interactions governing the retention of 15 solutes in 40 micellar reversed-phase liquid chromatographic systems using sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), methanol, n-propanol, and n-butanol as mobile phase additives are studied using linear solvation energy relationships (LSERs). The influence of solute properties on retention in MLC and the trends in the coefficients as a function of SDS and CTAB concentrations are investigated. The ability of the LSERs to account for the chemical interactions underlying solute retention is shown.

A comparison of predicted and experimental retention factors suggests that LSER formalism may not completely model the energetics of retention in MLC, but that the discrepancies, although systematic, are generally small. Finally, the effects of the addition of 0.035 M SDS to 10% methanol/90% water mobile phases on solute retention are discussed.

ACKNOWLEDGMENTS

This work was supported by the National Science Foundation, the University of Minnesota, Boehringer Ingelheim Pharmaceuticals, Inc., DGICYT (Spain, reference PS90-0026), and the University of Alcalá de Henares.