English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/11884
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:


Kinetic Spectroscopy of Erythrosin Phosphorescence and Delayed Fluorescence in Aqueous Solution at Room Temperature

AuthorsDuchowicz, Ricardo; Ferrer, M. Luisa ; Acuña, A. Ulises
KeywordsKinetic Spectroscopy
Erythrosin Phosphorescence
Issue DateMay-1998
PublisherAmerican Society for Photobiology
CitationPhotochemistry and Photobiology, 68, 494-501 (1998)
AbstractThe photophysics and polarization of the phosphorescence and delayed fluorescence of erythrosin in conditions compatible with the current biological applications of the dye (aqueous buffers at pH 7.4 at ambient temperatures) and in ethanol have been studied as a function of dye concentration (10 −7-10−5M) and temperature (245–333K). The emission decay is strictly single exponential and the detailed kinetic analysis of all the rate processes connected with the emitting T1 state showed that (1) the lowering of the emission lifetime at the higher temperatures is due to a very efficient self-quenching process, (2) the back intersystem crossing rate Tx S1 is temperature dependent (δETS7 kcal mol−1) but the T1S0 is not (Ea0.1 kcal mol−1) and (3) both intersystem crossing processes are very sensitive to solvent polarity, which accounts for the solvent dependence of the phosphorescence yield and lifetime. The high value of the phosphorescence anisotropy (r0= 0.25 lt 0.006) is independent of the excitation and emission wavelengths, and its evolution in time accurately reflects the rotational restrictions in solid solutions. The relevance of these findings to studies with protein-dye conjugates is also outlined to facilitate the design and interpretation of phosphorescence depolarization experiments that probe the (μs-ms dynamics of biomolecules and supramolecular systems.
Publisher version (URL)http://dx.doi.org/10.1111/j.1751-1097.1998.tb02505.x
Appears in Collections:(IQFR) Artículos
Files in This Item:
There are no files associated with this item.
Show full item record
Review this work

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.