Fluorescence in the system Eu(III) - oxytetracycline - co-ligand -sodium dodecylbenzene sulphonate micelles and its analytical application

摘要

Fluorescence enhancement of the Eu3+ - oxytetracycline (OTC) chelate by addition of phenanthroline (Phen) and trioctylphosphine oxide (TOPO) as well as micelles of anionic, catiomic and nonionic surfactants has been studied. As was found, in the presence of Phen as co-ligand and micelles of dodecylbenzene sulfonate as anionic surfactant the analytical signal increased by a factor of 8.5 and reached maximum value at pH 8.0 ± 0.5. The dynamic concentration range of OTC determination was found to be 8.0 x 10'8 - 4.0 x 10"5 M (R2 = 0.991) and the detection limit 5.3 x 10"8 M (3 a criterion). The procedure based on europium-sensitized fluorescence has been developed for the determination of OTC in chicken meat with the recovery of 98.0-103.3%.