Endre søk
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
In-line application of electric field in capillary separation systems Part I: Joule heating, pH and conductivity
Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemi och biomedicinsk vetenskap.
Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemi och biomedicinsk vetenskap.
Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemi och biomedicinsk vetenskap.
Early Development, Pharmaceutical and Analytical Research & Development, AstraZeneca, Sweden.
Vise andre og tillknytning
2008 (engelsk)Inngår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 75, nr 1, s. 83-90Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

This study concerns the technique electric field-assisted capillary liquid chromatography. In this technique, an electric field is applied over the separation capillary in order to provide an additional selectivity. In this technique, the electric field is applied in-line in the separation capillary and here the electric current is the factor limiting the magnitude of applied electric field. The influence of Joule heating and other factors on the current in such systems has been investigated.

The temperature in the capillary was first measured within a standard CE set-up, as function of effect per unit of length. Then the same cooling system was applied to an in-line set-up, to replicate the conditions between the two systems, and thus the temperature. Thus Joule heating effects could then be calculated within the in-line system. It was found that for systems applying an electric field in line, the direct influence from Joule heating was only relatively small.

The pH in the capillary was measured in the in-line set-up using cresol red/TRIS solutions as pH probe. Significant changes in pH were observed and the results suggested that electrolysis of water is the dominant electrode reaction in the in-line system. In summary, the observed conductivity change in in-line systems was found to be mainly due to the pH change by hydrolysis of water, but primarily not due the temperature change in the capillary column.

sted, utgiver, år, opplag, sider
2008. Vol. 75, nr 1, s. 83-90
HSV kategori
Forskningsprogram
Kemi
Identifikatorer
URN: urn:nbn:se:kau:diva-1913DOI: 10.1016/j.talanta.2007.10.032OAI: oai:DiVA.org:kau-1913DiVA, id: diva2:5008
Tilgjengelig fra: 2007-10-08 Laget: 2007-10-08 Sist oppdatert: 2017-12-07bibliografisk kontrollert
Inngår i avhandling
1. In-line application of electric fields in capillary separation systems
Åpne denne publikasjonen i ny fane eller vindu >>In-line application of electric fields in capillary separation systems
2006 (Engelska)Doktoravhandling, med artikler (Annet vitenskapelig)
Abstract [en]

The magnitude of an electric field possible to apply in a capillary separation system is limited, because a high electric field causes a too high current through the capillary. Application of the electric field in-line will give an increased conductivity in the column, further increasing the risk of too high currents. The conductivity changes were found to result from an overall increase in ionic strength within the electric field. The increase in ionic strength is caused by the increase in mobile phase ions with electrophoretic velocity against the flow, together with OH- or H3O+ ions (depending on polarity) formed at the inlet electrode. Further it was found that the use of a pressurized reservoir or splitting of the flow at the inlet electrode could significantly limit the conductivity changes and thereby the maximum applicable electric field strengths could be increased.

sted, utgiver, år, opplag, sider
Fakulteten för teknik- och naturvetenskap, 2006
Serie
Karlstad University Studies, ISSN 1403-8099 ; 2006:55
Emneord
capillary separation, conductivity, in-line, electric field assisted liquid chromatography
HSV kategori
Forskningsprogram
Kemi
Identifikatorer
urn:nbn:se:kau:diva-1197 (URN)91-7063-086-0 (ISBN)
Disputas
2006-12-15, 9C203, Karlstad University, Karlstad, 10:15
Opponent
Veileder
Tilgjengelig fra: 2007-10-08 Laget: 2007-10-08

Open Access i DiVA

Fulltekst mangler i DiVA

Andre lenker

Forlagets fulltekst

Personposter BETA

Blomberg, Lars

Søk i DiVA

Av forfatter/redaktør
Blomberg, Lars
Av organisasjonen
I samme tidsskrift
Journal of Chromatography A

Søk utenfor DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric

doi
urn-nbn
Totalt: 112 treff
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf