Linked Life Data

3149976

Source:http://linkedlifedata.com/resource/pubmed/id/3149976

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-6-12
pubmed:abstractText
The fluorescence decay I(t) and time-resolved spectra I(lambda, t) of some porphyrins and chlorins in ethanol and phosphate-buffered aqueous solution were investigated with a time-correlated single-photon-counting apparatus with a mode-locked Ar+ laser (514.5 nm) as the excitation source. The fluorescence of hematoporphyrin, mesoporphyrin and pheophorbide aa is considerably influenced by the conditions of aggregation (these compounds undergo aggregation in phosphate-buffered solution but not in ethanolic solution). The fluorescence decay of chlorin e6 which remains monomeric in both solvents is single exponential in all cases. The fluorescence spectra of hematoporphyrin, mesoporphyrin and pheophorbide a in phosphate-buffered solution are shifted with respect to the spectra obtained in ethanol; moreover, a new emission band (X band) appears, whose intensity increases on increasing the amount of equilibrium aggregates and shows a fast fluorescence decay. For hematoporphyrin and mesoporphyrin the appearance of the X band emission appears to be correlated with irreversible photoprocesses leading to fluorescent photoproducts. Analysis of the reported fluorescence spectra of cancer cells after incubation with hematoporphyrin derivative suggests that the fluorescent photoproducts might be formed also in vivo.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1011-1344
pubmed:author
pubmed:issnType
Print
pubmed:volume
1
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
103-13
pubmed:dateRevised
2007-7-23
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Time-resolved fluorescence spectroscopy of hematoporphyrin, mesoporphyrin, pheophorbide a and chlorin e6 in ethanol and aqueous solution.
pubmed:affiliation
Humboldt-University, Dept. of Physics, Berlin, G.D.R.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't