A Novel Route to Prepare Highly Reactive and Versatile Chromatographic Monoliths

Abstract

The copolymer poly(isocyanatoethyl methacrylate-co-methyl methacrylate-co-ethylene glycol dimethacrylate) (poly(IEM-co-MMA-co-EGDMA)) was developed as a novel, facile, highly reactive and versatile monolithic matrix, which was amenable to surface functionalization with a variety of nucleophilic modifiers based on the reactive isocyanate group, producing monoliths of various chemistries suitable for chromatography. The specific surface area, pore size distribution, porosity and morphology of the monolithic matrix were characterized using a mercury intrusion porosimeter and scanning electron microscopy (SEM), respectively. Thermal analysis results revealed that the monolith was thermally stable up to 307 °C. The success of the chemical modification of the monolithic matrix was confirmed by FT-IR, solid state (13) C NMR and XPS elemental analysis, showing the high ligand density of the modified monoliths. A ligand density of up to 2.33 mmol·mL(-1) was obtained for the 1-octanol modified monolith (M1) with an isocyanate group conversion of 96.9%, indicating a high efficiency of the modification reaction. The potential application of the monoliths was demonstrated by the separation of a series of compounds. The novel monolithic columns exhibited high mechanical stability, column efficiency and good repeatability and reproducibility.

Preparation of monomeric and polymeric β‐cyclodextrin functionalized monoliths for rapid isolation and purification of puerarin from Radix puerariae

“…The morphology of the mono‐β‐CD modified monolith was studied by SEM. Similar to the generic monolith 30, the morphology of β‐CD modified poly(IEM‐ co ‐MMA‐ co ‐EDMA) counterpart also consists of aggregates of irregular microglobules and interconnected large pores (Fig. 1A), which shows that the functionalization process did not greatly alter the morphology of the monoliths.…”

“… (A) Differential scanning calorimetry curves of β‐CD (dashed line), generic monolith (thin line) 30 and β‐CD functionalized monolith (thick line), and (B) solid‐state 13 C NMR spectra of generic 30 and β‐CD modified monoliths. …”

“…The preparation of poly(IEM‐ co ‐MMA‐ co ‐EDMA) monoliths was performed in a 100 mm×4.6 mm (id) stainless steel chromatographic column according to our previous work 30.…”

“…Recently, we reported in a short communication 30 describing the use of poly(isocyanatoethyl methacrylate‐ co ‐methyl methacrylate‐ co ‐ethylene dimethacrylate) (poly(IEM‐ co ‐MMA‐ co ‐EDMA)) as a novel, facile, highly reactive, and versatile monolithic matrix, and presented preliminary results demonstrating its versatility by functionalization with a variety of alcohols, amines, and thiols. The purpose of the present study is to further illustrate the versatility and effectiveness of the isocyanate monolith strategy by immobilization with β‐CD functionality and to demonstrate its potential application in single‐step highly rapid and efficient isolation of bioactive puerarin constituent from Radix puerariae crude extract.…”

Photo‐responsive block copolymer containing azobenzene group: Synthesis by reversible addition‐fragmentation chain transfer polymerization and characterization

“…The IEM molecule contains two flexible methylene groups that directly provide the space required for the isomerization of azobenzene. The methacrylate group of IEM can be homopolymerized or copolymerized with a large number of other vinyl monomers . Due to the special character of reactive isocyanate group, it is not easy to incorporate azobenzene moieties into IEM to form a new monomer.…”