Advanced

(Normal-Phase) Capillary Chromatography Using Acrylic Polymer-Based Continuous Beds

Maruska, Audrius; Ericson, Christer; Végvári, Ákos LU and Hjertén, Stellan (1999) In Journal of Chromatography A 837(1-2). p.25-33
Abstract
Microchromatographic separations of polar aromatic compounds (pyridine, 4-pyridylmethanol, 4-methoxyphenol, 2-naphthol, catechol, hydroquinone, resorcinol, 2,7-dihydroxynaphthalene) using continuous beds are described. The columns were prepared by a simple one-step in situ polymerization procedure: a solution of acrylic monomers, including the cross-linking agent piperazine diacrylamide, was polymerized in a fused-silica capillary pretreated with 3-(trimetoxysilyl) propyl methacrylate. The continuous bed formed contained a network of channels and was attached covalently to the wall of the silica capillary (100 mm I.D.) via its methacrylate groups. Therefore, the frit used in conventional, packed columns could be omitted. The separation... (More)
Microchromatographic separations of polar aromatic compounds (pyridine, 4-pyridylmethanol, 4-methoxyphenol, 2-naphthol, catechol, hydroquinone, resorcinol, 2,7-dihydroxynaphthalene) using continuous beds are described. The columns were prepared by a simple one-step in situ polymerization procedure: a solution of acrylic monomers, including the cross-linking agent piperazine diacrylamide, was polymerized in a fused-silica capillary pretreated with 3-(trimetoxysilyl) propyl methacrylate. The continuous bed formed contained a network of channels and was attached covalently to the wall of the silica capillary (100 mm I.D.) via its methacrylate groups. Therefore, the frit used in conventional, packed columns could be omitted. The separation mechanism is discussed, particularly with regard to whether the so-called aromatic

adsorption to the matrix itself is involved, an interaction first described by Gelotte [1] (the ligands, isopropyl and sulfonate groups, are not required for separation). This discussion is relevant to the question of whether the separation technique described should be classified as normal-phase or adsorption chromatography.

The mobile phase from the HPLC pump was split via an open capillary to get a flow rate through the continuous bed of about 100 nl /min. The beds were tested up to a pressure of 150 bar (8.8 bar /cm).

A continuous bed synthesized at a relatively low molar fraction of the cross-linker in the monomer mixture (16.5%) and high total concentration of the monomers (31.9% (w/v)) afforded the highest efficiency for the separation of the polar 21 organic compounds. Plate numbers up to 150 000 m were obtained and the run-to-run reproducibility was high. The selectivity of the separations was adjusted by changing the composition of the mobile phase (hexane–ethanol–methanol). The sample was applied by a diffusion-based injection technique. (Less)
Please use this url to cite or link to this publication:
author
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Continuous beds, Normal-phase chromatography, Adsorption chromatography, Microchromatography, Capillary chromatography, Aromatic adsorption
in
Journal of Chromatography A
volume
837
issue
1-2
pages
25 - 33
publisher
Elsevier
external identifiers
  • scopus:0037843153
ISSN
0021-9673
DOI
10.1016/S0021-9673(99)00088-6
language
English
LU publication?
no
id
64749564-6de3-4bcf-90de-c552a0d8063c (old id 3516333)
date added to LUP
2013-02-25 11:05:20
date last changed
2017-01-01 07:48:21
@article{64749564-6de3-4bcf-90de-c552a0d8063c,
  abstract     = {Microchromatographic separations of polar aromatic compounds (pyridine, 4-pyridylmethanol, 4-methoxyphenol, 2-naphthol, catechol, hydroquinone, resorcinol, 2,7-dihydroxynaphthalene) using continuous beds are described. The columns were prepared by a simple one-step in situ polymerization procedure: a solution of acrylic monomers, including the cross-linking agent piperazine diacrylamide, was polymerized in a fused-silica capillary pretreated with 3-(trimetoxysilyl) propyl methacrylate. The continuous bed formed contained a network of channels and was attached covalently to the wall of the silica capillary (100 mm I.D.) via its methacrylate groups. Therefore, the frit used in conventional, packed columns could be omitted. The separation mechanism is discussed, particularly with regard to whether the so-called aromatic<br/><br>
adsorption to the matrix itself is involved, an interaction first described by Gelotte [1] (the ligands, isopropyl and sulfonate groups, are not required for separation). This discussion is relevant to the question of whether the separation technique described should be classified as normal-phase or adsorption chromatography.<br/><br>
The mobile phase from the HPLC pump was split via an open capillary to get a flow rate through the continuous bed of about 100 nl /min. The beds were tested up to a pressure of 150 bar (8.8 bar /cm).<br/><br>
A continuous bed synthesized at a relatively low molar fraction of the cross-linker in the monomer mixture (16.5%) and high total concentration of the monomers (31.9% (w/v)) afforded the highest efficiency for the separation of the polar 21 organic compounds. Plate numbers up to 150 000 m were obtained and the run-to-run reproducibility was high. The selectivity of the separations was adjusted by changing the composition of the mobile phase (hexane–ethanol–methanol). The sample was applied by a diffusion-based injection technique.},
  author       = {Maruska, Audrius and Ericson, Christer and Végvári, Ákos and Hjertén, Stellan},
  issn         = {0021-9673},
  keyword      = {Continuous beds,Normal-phase chromatography,Adsorption chromatography,Microchromatography,Capillary chromatography,Aromatic adsorption},
  language     = {eng},
  number       = {1-2},
  pages        = {25--33},
  publisher    = {Elsevier},
  series       = {Journal of Chromatography A},
  title        = {(Normal-Phase) Capillary Chromatography Using Acrylic Polymer-Based Continuous Beds},
  url          = {http://dx.doi.org/10.1016/S0021-9673(99)00088-6},
  volume       = {837},
  year         = {1999},
}