Linked Life Data

20337396

Source:http://linkedlifedata.com/resource/pubmed/id/20337396

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
15
pubmed:dateCreated
2010-3-26
pubmed:abstractText
Enantioselective phosphorescence lifetime detection was combined with chiral cyclodextrin-based electrokinetic chromatography for the analysis of camphorquinone (CQ). A time-gated detection system based on a pulsed light-emitting diode for excitation at 465 nm was developed for the online lifetime determination. The background electrolyte for the chiral separation consisted of 20 mM alpha-cyclodextrin (alpha-CD), 10 mM carboxymethyl-beta-CD, and 25 mM borate buffer at pH 9.0. The separation of (+)-CQ and (-)-CQ is caused by a difference in association constants of these enantiomers with alpha-CD. Under the separation conditions, different phosphorescence lifetimes were obtained for (+)-CQ and (-)-CQ (tau = 384 +/- 8 and 143 +/- 5 micros, respectively), which could be used to distinguish the enantiomers. This selectivity in detection is based on a difference in protection of the enantiomers against phosphorescence quenching after their complexation with alpha-CD. Concentration detection limits were 2 x 10(-7) and 1 x 10(-6) M for (+)-CQ and (-)-CQ, respectively. After correction for the lifetime shortening by triplet-triplet annihilation at higher CQ concentrations, a linear dynamic range was obtained from the detection limit up to 2 mM. The system was used to determine the enantiomeric impurity levels of commercial samples of (+)-CQ and (-)-CQ; 0.2% and 0.1%, respectively.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1520-6882
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
81
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6226-33
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Phosphorescence for sensitive enantioselective detection in chiral capillary electrophoresis.
pubmed:affiliation
Department of Analytical Chemistry and Applied Spectroscopy, Laser Centre Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't