Estimation of Eu(3+) in bulk uranium by ligand sensitized fluorescence in dimethyl sulphoxide

Ligand sensitized fluorescence of europium ion using thenoyltrifluoroacetone (TTA) as a sensitizing ligand and dimethyl sulphoxide (DMSO) as a solvent is studied for the first time. TTA ligand enhances the fluorescence of Eu(3+) by a factor of 40000 in DMSO. Linearity is obtained for a concentration range of 0.076-7.6ng/mL of Eu(3+) with a detection limit of 7.6pg/mL. The quenching of Eu(3+)-TTA fluorescence by uranium matrix was studied in different solvents and found to be less in DMSO. Consequently, estimation of Eu(3+) in a large excess of uranium becomes a possibility without the need to separate uranium from the solution, which has been demonstrated in this paper. Satisfactory results are obtained when Eu(3+) is present at a concentration of 0.6μg/g in uranium.