Linked Life Data

12812292

Source:http://linkedlifedata.com/resource/pubmed/id/12812292

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2003-6-18
pubmed:abstractText
We have investigated the spectral properties and emission characteristics of fluorescein-5-thiocarbamoyl-N,N'-caproate (FITC-ACA) to examine the origin of the complex emission decay often observed in fluorescein-labeled molecules. The covalent attachment of fluorescein to epsilon-amino-n-caproic acid does not perturb the prototropic transitions of the chromophore or the general fluorescence characteristics of the various prototropic forms. However, both the monoanion and dianion forms of FITC-ACA are quenched relative to free fluorescein and exhibit a complex emission decay that is described by two discrete lifetimes. The thiourea group that links the chromophore to the caproic acid is shown to modulate the emission properties of the FITC-ACA. We show that the emission decay can also be analyzed using the asymmetric distribution model of Alcala et al. In this analysis, the tauL and tauu parameters that represent the lower and upper lifetime limits of the distribution reflect the quenched (0 ns) and unquenched lifetimes, respectively. The beta parameter that describes the distribution of lifetimes between the two limiting states can be related to the quenching efficiency of the thiourea group and to the structure and dynamics of the FITC-ACA molecule.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0031-8655
pubmed:author
pubmed:issnType
Print
pubmed:volume
77
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
502-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
The thiourea group modulates the fluorescence emission decay of fluorescein-labeled molecules.
pubmed:affiliation
Russell Grimwade School of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Australia. n.klonis@latrobe.edu.au
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't