Statistical solvent optimization for the separation of geometric isomers of retinol by high-performance liquid chromatography.

A systematic approach to the optimization of solvents for separation of isomers of retinol by straight-phase high-performance liquid chromatography is described. The optimum resolution of the 11-cis isomer from the 13-cis isomer required solvent characteristics different from those for the optimum resolution of the 9-cis isomer from the all-trans isomer. A compromise solvent composition produced good resolution of all four isomers in less than 12 min when used with an Excalibar column packed with 5-micron spherical silica.