Linked Life Data

15499930

Source:http://linkedlifedata.com/resource/pubmed/id/15499930

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2004-10-25
pubmed:abstractText
In this work we demonstrate that the X-Terra RP18 stationary phase, specially designed for the analysis of basic compounds in liquid chromatography, may be successfully used in capillary electrochromatography. Although this packing material does not afford a sufficient electroosmotic flow with classical hydro-organic mobile phases, the addition of a surfactant that adsorbs onto the stationary phase allows to generate a sustainable electroosmosis flow (EOF), the direction of which depends on the charge of the surfactant. The way of manipulating the electroosmotic flow is described (nature and concentration of the added surfactant, proportion of the organic modifier in the mobile phase, pH). It is then demonstrated that high efficiencies can be reached with this packing material (up to 220,000 plates/m with a mean diameter particles of 3.5 microm) when it is operated at high linear velocities. Then the separations of different classes of compounds such as amphenicol antibiotics, macrolide antibiotics or basic test solutes with mobile phases with pH up to 10.8 are described. The influence of the addition of sodium dodcylsulfate (SDS) to the mobile phase on the retention is described and the selectivity of the X-Terra RP18 stationary phase is compared to that of a more traditional phase, i.e. Hypersil C18 stationary phase with SDS added to the mobile phase. However, it is shown that a good repeatability of the retention factors can only be obtained when the ionization of the compounds is totally suppressed since electrolysis of the buffered hydro-organic mobile phase occurs in the buffer reservoirs leading to a variation of the mobile phase pH and consequently to a modification of the ionization degree of the solutes having their pKa close to the mobile phase pH.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9673
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
1049
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
171-81
pubmed:dateRevised
2009-1-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Separation of basic compounds by capillary electrochromatography on an X-Terra RP18 stationary phase.
pubmed:affiliation
Laboratoire des Sciences et Stratégies Analytiques, UMR5180, Bâtiment 308D, Université Claude Bernard Lyon I, 69622 Villeurbanne Cedex, France.
pubmed:publicationType
Journal Article, Evaluation Studies