INVESTIGADORES
MASSAD Walter Alfredo
artículos
Título:
Interaction of UO22+ with sodium dodecyl sulfonate micelles based
Autor/es:
PATRICIA REPOSSI; WALTER A. MASSAD; GERARDO A. ARGÜELLO
Revista:
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
Referencias:
Año: 2005 vol. 265 p. 85 - 90
ISSN:
0236-5731
Resumen:
The interaction between the U(VI) and a sodium dodecyl sulfonate (SDS)
micelle was studied for intensity and emission lifetime. The
measurements of the uranyl ion were done in a 1M H3PO4 medium. The self quenching rate constant (ksq)
shows a larger value in micellar than in a SDS monomeric solution. This
fact should be interpreted by micelles favoring the localized
concentration of UO22+ species. Dynamic and
static quenching was observed in the interaction between uranyl ion and
the surfactant monomer before the induced critical micelle
concentration (icmc) (1 mM) yielding a value of kD = (134±2) . 10M-1 and kS= (16±2) . 102M-1
for the dynamic and static quenching constant, respectively. A
quantitative description of the binding was obtained by monitoring the
emission lifetime of the uranyl excited state as a function of the
surfactant concentration (titration curve), assuming that the observed
lifetime is related to a weighted fraction of rate constants for the
bound and unbound species.