gma-edma and glycidyl-methacrylate

Topics: Epoxy Compounds; Glycopeptides; Indoles; Isoindoles; Methacrylates; Methylmethacrylates; Organometallic Compounds; Polymers; Transferrin

In order to investigate the effect of the linking spacer on the enantioseparation ability of β-cyclodextrin (β-CD) functionalized polymeric monoliths, three β-CD-functionalized organic polymeric monoliths with different spacer lengths were prepared by using three amino-β-CDs, i.e. mono-6-amino-6-deoxy-β-CD, mono-6-ethylenediamine-6-deoxy-β-CD, mono-6-hexamethylenediamine-6-deoxy-β-CD, as starting materials. These amino-β-CDs reacted with glycidyl methacrylate to produce functional monomers which were then copolymerized with ethylene dimethacrylate. The enantioseparation ability of the three monoliths was evaluated using 14 chiral acidic compounds, including mandelic acid derivatives, nonsteroidal anti-inflammatory drugs, N-derivatized amino acids, and chiral herbicides under optimum chromatographic conditions. Notably, the poly(GMA-NH2-β-CD-co-EDMA) column provides higher enantioresolution and enantioselectivity than the poly(GMA-EDA-β-CD-co-EDMA) and poly(GMA-HDA-β-CD-co-EDMA) columns for most tested chiral analytes. Furthermore, the enantioseparation performance of triazole-linker containing monoliths was compared to that of ethylenediamine-linker containing monoliths. The results indicate that the enantioselectivity of β-CD monolithic columns is strongly related to the length and type of spacer tethering β-CD to the polymeric support.

Topics: Amination; Amino Acids; Anti-Inflammatory Agents, Non-Steroidal; beta-Cyclodextrins; Chromatography, High Pressure Liquid; Epoxy Compounds; Ethylenediamines; Mandelic Acids; Methacrylates; Methylmethacrylates; Polymerization; Stereoisomerism; Triazoles

A new thermally switchable molecularly imprinted monolith for the selective capture and release of proteins has been designed. First, a generic poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith reacted with ethylenediamine followed by functionalization with 2-bromoisobutyryl bromide to introduce the initiator for atom transfer radical polymerization. Subsequently, a protein-imprinted poly(N-isopropylacrylamide) layer was grafted onto the surface of the monolithic matrix by atom transfer radical polymerization. Scanning electron microscopy and energy-dispersive X-ray spectroscopy of the cross-sections of imprinted monoliths confirmed the formation of dense poly(N-isopropylacrylamide) brushes on the pore surface. The imprinted monolith exhibited high specificity and selectivity toward its template protein myoglobin over competing proteins and a remarkably large maximum adsorption capacity of 1641 mg/g. Moreover, this "smart" imprinted monolith featured thermally responsive characteristics that enabled selective capture and easy release of proteins triggered only by change in temperature with water as the mobile phase and avoided use of stronger organic solvents or change in ionic strength and pH.

Topics: Adsorption; Chromatography; Epoxy Compounds; Hydrogen-Ion Concentration; Methacrylates; Methylmethacrylates; Microscopy, Electron, Scanning; Molecular Imprinting; Myoglobin; Osmolar Concentration; Polymerization; Polymers; Temperature

Poly(glycidyl methacrylate-co-ethylene dimethacrylate) (poly(GMA-co-EDMA)) is most frequently used as parent monolith to obtain stationary phases with a variety of surface chemistries for liquid chromatography and capillary electrochromatography. Functionalization is performed by opening the accessible 2,3-epoxypropyl groups of the monolith with a suitable reagent. The number of 2,3-epoxypropyl groups which are accessible before and after the functionalization reaction, and the grafting yield, are important parameters, required both to optimize functionalization and to interpret the chromatographic performance of functionalized monoliths. In this work, a method capable of providing this information for parent and functionalized poly(GMA-co-EDMA) monoliths prepared both in silica capillaries and in other supports is proposed. First, sulfuric acid and lithium aluminium hydride (LiAlH4) are sequentially used to release the 2,3-epoxypropyl groups as glycerol, which is subsequently determined by GC. About 6.0mmol of 2,3-epoxypropyl groups per gram of monolith was found in this work for the parent monoliths prepared in silica capillaries using UV-initiation. The monoliths were also functionalized using ammonia (NH3), diethylamine (DEA) and epinephrine, and the amount of residual 2,3-epoxypropyl groups, and hence the functionalization yield, were established by also measuring the GC peak of glycerol. The amounts of 2,3-epoxypropyl groups and the derivatization yields were established with RSDs of 1.7 and 3.4%, respectively. The proposed method was also applied to the characterization of poly(GMA-co-EDMA) monoliths prepared in glass vials. Significant differences with respect to those prepared in 100μm I.D. silica capillaries were evidenced.

Topics: Capillary Electrochromatography; Chemistry Techniques, Analytical; Chromatography, Gas; Epoxy Compounds; Methacrylates; Methylmethacrylates; Silicon Dioxide

A facile and efficient "one-pot" copolymerization strategy was used for the preparation of sulfonamide drug (SA) functionalized monolithic columns. Two novel SA-immobilized methacrylate monolithic columns, i.e. poly(GMA-SMX-co-EDMA) and poly(GMA-SAA-co-EDMA) were prepared by one-pot in situ copolymerization of the drug ligand (sulfamethoxazole (SMX) or sulfanilamide (SAA)), the monomer (glycidyl methacrylate, GMA) and the cross-linker (ethylene dimethacrylate, EDMA) within 100 μm i.d. capillaries under optimized polymerization conditions. The physicochemical properties and column performance of the fabricated monolithic columns were characterized by elemental analysis, scanning electron microscopy and micro-HPLC. Satisfactory column permeability, efficiency and separation performance were obtained on the optimized poly(GMA-SMX-co-EDMA) monolithic column for small molecules, such as a standard test mixture and eight aromatic ketones. Notably, it was found that the poly(GMA-SMX-co-EDMA) monolith showed a selective affinity to trypsin, while the poly(GMA-SAA-co-EDMA) monolith containing sulfanilamide did not exhibit such affinity at all. This research not only provides a novel monolith for the selective isolation and purification of trypsin, but it also offers the possibility to easily prepare novel drug functionalized methacrylate monoliths through a one-pot copolymerization strategy.

Topics: Chemistry Techniques, Analytical; Chromatography, High Pressure Liquid; Epoxy Compounds; Methacrylates; Methylmethacrylates; Microscopy, Electron, Scanning; Permeability; Polymerization; Sulfamethoxazole; Trypsin

The protein modified monolithic column in affinity capillary electrochromatography (CEC) has attracted considerable attention over the past decades because of its great enantioseparation ability. A porous polymethacrylate ester-based capillary monolithic column poly (glycidyl methacrylate-co-ethyleneglycol dimethacrylate) (poly (GMA-co-EDMA)) was prepared by in situ co-polymerization. The process was initiated thermally by azobisisobutyronitrile (AIBN). The polymerization mixture contained GMA as the function monomer and EDMA as the crosslinking agent with 1,4-butanediol and 1-propanol as the binary porogen solvent. Under the optimized reaction conditions, including the proportion of monomer and porogens, reaction temperature etc, the column exhibited a uniform structure, sufficient permeability and excel- lent pressure resistance. The separation of alkyl benzenes on the column was mainly based on typical reversed-phase chromatographic retention mechanism. The reproducibility and stability were good with RSDs less than 9. 0%. A pepsin functionalized organic polymer monolith was prepared by covalently bonded pepsin to poly(GMA-co-EDMA) monolith with glutaraldehyde as a spacer based on the activity of epoxide group. The enantioseparation performance of the pepsin affinity monolith for basic enantiomers has been investigated by CEC. Nefopam, amlodipine, citalopram and chlorpheniramine were resolved, and baseline separations of nefopam, amlodipine, citalopram were achieved. The influences of pH, operating voltage, temperature and sample quantity used on the chiral separation were studied. The chiral recognition mechanism of enantiomers on the monolithic column in CEC is discussed. This work developed a new method for the prepataion and application of protein affinity monolith in CEC.

Topics: Butylene Glycols; Capillary Electrochromatography; Chromatography, Reverse-Phase; Epoxy Compounds; Methacrylates; Methylmethacrylates; Pepsin A; Polymers; Polymethacrylic Acids; Porosity; Reproducibility of Results; Stereoisomerism