Interaction of U022+ with sodium dodecyl sulfonate micelles based on fluorescence data

P. REPOSSI; W. A. MASSAD; G. A. ARGUELLO

JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY

Akademiai Kiado, Budapest

Lugar: Springer, Dordrecht; Año: 2005 vol. 265 p. 85 - 85

0236-5731

p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; mso-pagination: none">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 H3P04 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 U022+ species. Dynamic and static quenching was observed in the interaction between uranyl ion and the surfactant monomer before the induced critical micelle concentration (icmc) (1mM) yielding a value of Kd=(134±2)•lOM-1 and KS =(16±2)•1O2M_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 th