Improved chromatographic performances of glycidyl methacrylate anion-exchange monolith for fast nano-ion exchange chromatography

An efficient and reproducible photopolymerized poly(glycidyl methacrylate‐co‐ethylene dimethacrylate) was synthesized in Teflon‐coated fused‐silica capillaries (100 μm id) and functionalized by reaction of triethylamine with reactive epoxy groups. We report here the successful transfer of a standard polymerization mixture optimized for the thermally initiated synthesis of glycidyl‐based monolith to photo‐induced polymerization. The monolith obtained after optimization of the photo‐initiation conditions was characterized in reverse‐phase chromatography evaluating its suitability in terms of efficiency, retention and hydrodynamic permeability. Reproducibility of the photo‐induced procedure was satisfactory with RSD below 6% for retention and efficiency and slightly higher for hydrodynamic permeability (12%). The functionalized generic support was then used in nano‐ion‐exchange chromatography. Efficiencies up to 75 000 plates/m, ion‐exchange capacity of 8 nano‐equivalents/cm of monolithic column, with a combination of a satisfactory hydrodynamic permeability allowed to perform fast separations of five inorganic anions in <3 min maintaining baseline resolution. The efficiency of the monolith was not retention‐dependent, demonstrating its wide range of possible applications for highly retained anions.