Macrocyclic polyamine‐modified poly(glycidyl methacrylate‐<b><i>co</i></b>‐ethylene dimethacrylate) monolith for capillary electrochromatography

A novel and simple method for the separation of major vitamin B analytes, such as thiamine, riboflavin, nicotinamide, vitamin B4, pyridoxine, has been developed by CEC using the monolithic column. It has been found that the baseline separation of the five analytes could be achieved with 5.0 mM phosphate buffer at pH 4.0. Compared with the open-tubular capillary and the bared capillary columns, the poly(butylmethacrylate-co-ethylene glycol dimethacrylate) monolithic capillary could exhibit the best resolution in the analysis. Then the method was validated and the linear calibration ranges were obtained with correlation coefficients more than 0.997. The precision and the recovery were also investigated and showed a good result. Furthermore, the proposed method was successfully applied to assay the concentration of vitamin B analytes and the metabolic situation in human urine samples.

Section: Optimizing the Separation Conditionsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Assay of vitamin B in urine by capillary electrochromatography with methacrylate‐based monolithic column

Wei

Qiao

et al. 2010

“…Acrylates and methacrylates represent a very rich family of monomers enabling access to numerous functionalities residing in the ester part of the molecule that are easily copolymerized with a variety of crosslinkers such as ethylene dimethacrylate (EDMA), butanediol diacrylate, and trimethylolpropane trimethacrylate to afford both the desired well‐controlled porous structure and pore surface chemistry. Interestingly, glycidyl methacrylate leads the list of monomers used for the preparation of monolithic capillary columns for CEC 85–90. We have introduced this monomer in the preparation of porous polymer beads already in 1975 91, and the first monoliths consisted of this monomer as well 2, 3.…”

Section: Polymethacrylate Copolymersmentioning

confidence: 99%

CEC: Selected developments that caught my eye since the year 2000

Švec

2009

During the last decade, a number of new developments have emerged in the field of capillary electrochromatography (CEC). This paper focuses only on monolithic columns prepared from synthetic polymers. Monolithic columns have become a well-established format of stationary phases for CEC immediately after their inception in the mid 1990s. They are readily prepared in situ from liquid precursors. Also, the control over both porous properties and surface chemistries is easy to achieve. These advantages make the monolithic separation media an attractive alternative to capillary columns packed with particulate materials. Since the number of papers concerned with just this single topic of polymer-based monolithic CEC columns is large, this overview describes only those approaches this author found interesting. KeywordsMonolith; Capillary; Electrochromatography; Microfluidic devices; Review PrologueIt is the second half of the 1990s. The monoliths are in their infancy with a multiplicity of their formats being developed just within the last few years [1][2][3][4]. Only a handful of groups were working with these new materials and exploring their applications mostly for the separations in liquid chromatography. At the same time, electrochromatography rose from ashes like the mythical Phoenix. This separation method has been proposed by Pretorius already in 1974 [5]. He realized the advantage of the flat flow profile generated by electroosmotic flow (EOF) that was supposed to reduce peak broadening thus affording better column efficiency in both thin layer and column chromatography. However, for a couple of decades his technique has been almost forgotten. The 1990s featured search for new microseparation methods with vastly enhanced efficiencies, peak capacities, and selectivities needed for the emerging fields of life science and pharmaceuticals and CEC became one of the targets. The new interest in CEC has also been fueled by discoveries such as that by Smith who demonstrated that extreme column efficiencies exceeding one million of plates could be achieved using CEC in packed capillary columns although these were difficult to reproduce [6]. Results like these evoke curiosity of many researchers and jump started CEC.Capillary electrochromatography has been defined as a high-performance liquid phase separation technique carried out in columns packed with media containing ionizable functionalities that utilizes flow driven by electroosmosis and enables to achieve significantly improved performance compared to high performance liquid chromatography (HPLC). The Correspondence: Frantisek Svec, The Molecular Foundry, E.O. Lawrence Berkeley National Laboratory, Berkeley, CA 94720-8197, USA. fsvec@lbl.gov Phone +510 486 7964. NIH Public Access Author ManuscriptElectrophoresis. Author manuscript; available in PMC 2010 June 1. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript frequently published definitions that call CEC a hybrid of capillary electrophoresis (CE) and HPLC are actually not comple...

“…So far, there have been three different types of organic polymeric monoliths described by various research groups, including acrylate ester-based monoliths [20][21][22][23], acrylamide-based monoliths [24,25] and styrene-based monoliths [26,27]. Whereas most literatures on polymeric monolithic columns in CEC has focused on methacrylate-based monoliths due to their unique properties, such as highchemical stability and excellent mechanical property in a wide pH range [28,29].…”

Section: Introductionmentioning

confidence: 98%

Preparation and evaluation of the highly cross‐linked poly(1‐hexadecane‐co‐trimethylolpropane trimethacrylate) monolithic column for capillary electrochromatography

Feng

et al. 2009

In this paper, a novel highly cross-linked porous monolithic stationary phase having a long alkyl chain ligand (C16) was introduced and evaluated in CEC. The monolithic stationary phase was prepared by in situ copolymerization of 1-hexadecene, trimethylolpropane trimethacrylate, and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) in the presence of ternary porogenic solvent (cyclohexanol/1,4-butanediol/water). In preparing monoliths, the ternary cross-linker trimethylolpropane trimethacrylate was usually applied to preparing molecularly imprinted polymers or molecularly imprinted solid-phase extraction, instead of binary cross-linker ethylene dimethacrylate. 1-Hexadecene was introduced to provide the non-polar sites (C16) for chromatographic retention, while AMPS was used to generate the EOF for transporting the mobile phase through the monolithic capillary. Monolithic columns were prepared by optimizing proportion of porogenic solvent and AMPS content in the polymerization solution as well as the cross-linkers. The monolithic stationary phases could generate a strong and stable EOF in various pH values and exhibit an RP-chromatographic behavior for neutral compounds. For charged compounds, the separation was mainly based on the association of hydrophobic, electrostatic and electrophoretic interaction.