Various Strategies in Post-Polymerization Functionalization of Organic Polymer-Based Monoliths Used in Liquid Phase Separation Techniques

Abstract

This review article is aimed at summarizing the various strategies that have been developed so far for post-polymerization functionalization (PPF) of organic polymer-based monoliths used in liquid phase separation techniques, namely HPLC at all scales and capillary electrochromatography (CEC). The reader will find the organic reactions performed on monolithic columns for grafting the chromatographic ligands needed for solving the separation problems on hand. This process involves therefore the fabrication of template monoliths that carry reactive functional groups to which chromatographic ligands can be covalently attached in a post-polymerization kind of approach. That is, the template monolith that has been optimized in terms of pore structure and other morphology can be readily modified and tailor made on column to fit a particular separation. The review article will not only cover the various strategies developed so far but also describe their separation applications. To the best of our knowledge, this review article will be the first of its kind.

Recent developments and applications of polymer monolithic stationary phases

“…Two recent reviews on post‐synthesis modification of the surface chemistry of polymer monoliths were published by Ribeiro et al 22 . and Alharthi et al 54 . A recent development involves the preparation of hydrophilic polymer monoliths based on poly(2‐hydroxyethyl methacrylate) containing magnetic nanoparticles and amine‐modified carbon nanotubes via photopolymerization of a HIPE described by Fresco‐Cala et al 55 .…”

“…Alternatively, post-polymerization functionalization strategies, for example, applying grafting approaches or using reactive monomers for subsequent modification can also be utilized. Two recent reviews on post-synthesis modification of the surface chemistry of polymer monoliths were published by Ribeiro et al 22 and Alharthi et al 54 A recent development involves the preparation of hydrophilic polymer monoliths based on poly(2-hydroxyethyl methacrylate) containing magnetic nanoparticles and amine-modified carbon nanotubes via photopolymerization of a HIPE described by Fresco-Cala et al 55 They claimed that incorporation of more than 40 wt% of nanoparticles provided a new functionality, magnetism.…”

Macroporous Polymer Monoliths in Thin Layer Format

“…In both cases, the successful protein immobilization can be achieved during 2-4 h at mild conditions (pH 7.4, 37 • C). In general, monolithic layers can be post-modified by the techniques already applied for flow-through polymer monoliths and summarized in the recent review [83].…”

Some factors affecting pore size in the synthesis of rigid polymer monoliths: Theory and its applicability

“…The excellent separation efficiency within a short time has been testified by many researchers for both low molecular compounds and macromolecules even when the short monolithic columns were applied 3–7 . The realization of all high‐performance liquid chromatography (HPLC) modes for polymer monolithic sorbents appeared to be possible because of relative simplicity of their synthesis and covalent modification needed for adsorptive functionalization 8,9 . Despite the recent developments of novel kinds of monoliths (soft gel monoliths, 10 superporous cryogels, 11 inorganic, 12 and hybrid monoliths, 13 high internal phase emulsion monoliths, 14 etc.)…”