QUANTITATIVE RETENTION-STRUCTURE AND RETENTION-ACTIVITY RELATIONSHIPSOF BARBITURATES BY MICELLAR LIQUID-CHROMATOGRAPHY

Studies on the structural requirements of chromatographic surfaces to emulate in vitro the partitioning process in biomembranes are of great interest. The use of micellar mobile phases in RPLC modifies the hydr ophobicity of the stationary phase and provides hydrophobic and electr ostatic sites of interaction as a consequence of the adsorption of sur factant monomers to the chromatographic surface. Modified stationary p hases in MLC could be structurally similar to biomembranes, but thorou gh studies are necessary to confirm this. In this paper we focus our a ttention on barbiturates. The influence of the nature and concentratio n of the surfactant (Brij 35, SDS and CTAB) and the mobile phase pH on the retention of 13 barbiturates in modified C-18 stationary phases i s studied. Quantitative structure-retention and structure-activity rel ationships for the barbiturates with different surfactants are propose d and compared with those obtained using hydro-organic mobile phases. (C) 1998 Elsevier Science B.V. All rights reserved.