Chiral Monolithic Columns for Enantioselective Capillary Electrochromatography Prepared by Copolymerization of a Monomer with Quinidine Functionality. 1. Optimization of Polymerization Conditions, Porous Properties, and Chemistry of the Stationary Phase

摘要

MonolidIic columns for chiral capillary electrochromatog- raphy have been prepared widIin dIe confines of untreated fused-silica capillaries in a single step by a simple copo- lymerization of mixtures of O-[2-(methacryloyloxy)edIyl- carbamoyl]-! 0, !!-dihydroquinidine, edIylene dimedJaClyl- ate, and glycidyl medIacrylate or 2-hydroxyedIyl medI- acrylate in dIe presence of mixture of cyclohexanol and !-dodecanol as a porogenic solvent. The porous proper- ties of dIe monolidIic columns can easily be controlled Idtrough changes in dIe composition of dIe binary poro- genic solvent. AldIough bodI dIermal- and UV light- initiated polymerizations afford useful capillary columns, monolidIs prepared using dIe former approach exhibit ~ better chromatographic properties. The ability to control ~ pore size independently of dIe polymerization mixture ~ composition enables dIe preparation of monolidIs widI varying percentages of dIe chiral monomer and cross. linker, as well as dIe optimization of dIeir separation properties. Very good separations of model racemate (R,S)-N-3,5-dinitrobenzoylleucine were achieved using an optimized monolidIic CEC column, widI high efficiencies " of up to 74 000 plates/m for dIe retained peaks.