CEC with new monolithic stationary phase based on a fluorinated monomer, trifluoroethyl methacrylate

Abstract

A new, fluorinated monolithic stationary phase for CEC was first synthesized by a single-stage, thermally initiated copolymerization of a fluorinated monomer, 2,2,2-trifluoroethyl methacrylate (TFEM) and ethylene dimethacrylate (EDMA) in the presence of a porogen mixture. In this preparation, 2-acrylamido-2-methyl-1-propanesulfonic acid was used as the charge-bearing monomer. The porogen mixture was prepared by mixing isoamylalcohol and 1,4-butanediol. A clear increase in the electroosmotic mobility was observed with increasing pH. The electroosmotic mobility decreased with increasing ACN concentration. Poly(TFEM-co-EDMA) monolith prepared under optimized polymerization conditions was successfully used in the separation of alkylbenzenes and phenols by CEC. The best chromatographic separation for alkylbenzenes was performed with lower ACN concentrations (i.e. 60% v/v) with respect to the common acrylic-based CEC monoliths. The theoretical plate numbers up to 220 000 plates/m were achieved in the reversed phase separation of phenols. Poly(TFEM-co-EDMA) monolith also allowed the simultaneous separation of aniline and benzoic acid derivatives by a single run and by using a lower ACN concentration in the mobile phase with respect to the similar electrochromatographic separations. A stable retention behaviour in reversed phase separation of alkylbenzenes was obtained with the poly(TFEM-co-EDMA) monolith.

Occurrence investigation of perfluorinated compounds in surface water from East Lake (Wuhan, China) upon rapid and selective magnetic solid-phase extraction

“…Lately, Oleschuk deduced that the F-F interaction may be a special instantaneous dipole-dipole force21. Although the fundamental of the F-F interaction remains to be elucidated, researchers have developed a number of ways to exploit this attraction for chemical purification and separation2223. Most recently, combining the selective recognition ability of F-F interaction and rapid magnetic separation property of Fe 3 O 4 nanoparticles (NPs), two useful magnetite materials were prepared for extraction and pre-concentration of PFCs in surface water samples2425.…”

Synthesis of a monolithic, micro-immobilised enzyme reactor via click-chemistry

“…In the blank runs performed using an empty capillary tube in the same length with monolithic IMER in micro-HPLC, the recording of UV absorbance is started when the substrate solution containing 400 μM BTEE is fed into the tube. An "S"-shaped curve is obtained for variation of absorbance of the outlet stream as explained previously [31]. In the case of monolithic IMER, some part of BTEE fed into the reactor is hydrolysed by the immobilised enzyme.…”

“…For this purpose, monodisperse-porous poly(GMA-co-EDMA) particles 7.5 μm in size were prepared by seeded microsuspension copolymerisation of respective monomers as described elsewhere [31,32]. In order to attach CT onto poly(GDMAco-EDMA) particles, first epoxypropyl groups of particles (1 g) were converted to diol form by an acidic hydrolysis.…”

“…22 cm in length (530 μm ID) was performed according the procedure described previously [30,31]. The polymerisation mixture containing 18.7% w/w GMA, 6.2% w/w EDMA, 37.4% w/w n-PrOH, 29.9% w/w BD, 7.5% w/w phosphate buffer at pH 7 and 0.3% w/w AIBN was fed into the silanised capillary at a flow rate of 100 μL/min for 5 min.…”

Fluorinated monolithic column for CEC

“…CEC. To the best of our knowledge, only a few fluorine‐containing monoliths have been reported as a stationary phase 8, 9. Yurtsever et al 8 were the first to report the preparation protocol and the performance of a negatively charged fluorinated monolith.…”