Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1994-9-21
pubmed:abstractText
On-column concentration of neutral molecules was achieved for the first time in micellar electrokinetic chromatography by means of field-amplified sample stacking. The stacking process was accomplished by dissolving the neutral analytes in a low-concentration micellar solution that was still above the critical micelle concentration. The lower total ionic strength in the sample buffer compared to the electrophoresis buffer allowed the negatively charged micelles to migrate rapidly into the boundary between the sample and the running buffer where they slow down. This field-amplified sample stacking was achieved by using normal or reversed electrode polarity and produced a 75-85-fold increase in sensitivity for 1,2,4,7- and 1,2,4,8-tetrachlorodibenzo-p-dioxins. The peak area counts obtained from the sample stacking process were proportional to the sample volume injected, and the stacking efficiency was dependent on the micellar concentration. The best stacking efficiency was obtained when the micelle concentration was slightly higher than the critical micelle concentration. When the injection volume was relatively small, the normal-polarity stacking procedure produced a higher stacking efficiency. However, when the injection volume was large, reversed polarity produced a higher stacking efficiency because the non-uniform distribution of the electrical field strength had been eliminated.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9673
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
673
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
125-32
pubmed:dateRevised
2009-1-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Field-amplified sample stacking in micellar electrokinetic chromatography for on-column sample concentration of neutral molecules.
pubmed:affiliation
US Centers for Disease Control and Prevention (CDC), Division of Environmental Health Laboratory Sciences, Toxicology Branch, Atlanta, GA 30341.
pubmed:publicationType
Journal Article