Waruna Kiridena and Colin F. Poole
The solvation parameter model is used to characterize the retention properties of a cyanopropylsiloxane-bonded, silica-based high-performance thin-layer chromatography layer with methanol–water mobile phases. Dipole-type interactions do not contribute to retention while the layer cohesion and hydrogen-bond acidity of water dominate retention for predominantly aqueous mobile phases, and although retention is weak for predominantly methanol mobile phases, retention is favored by lone pair–lone pair electron interactions and diminished by hydrogen-bond type interactions in the mobile phase. The solvation parameter model is used to construct retention maps for the solvent optimization of the separation of steroids with an average difference of 0.046 RF units between experimental and predicted values.