Luminescence quenching of Eu(III) carboxylates by Cu(II) in a>composite polymer xerogel film

B. C. BARJA; A. REMORINO; P. F. ARAMENDIA

PHOTOCHEMISTRY AND PHOTOBIOLOGY

American Society for Photobiology

Año: 2006 vol. 82 p. 43 - 49

0031-8655

Three Eu(III) luminescent compounds were separately entrapped in a xerogel porous silica matrix and finely ground particles of it were deposited on a glass support with polyvinylacetate (PVAc) as a binder to build a thin film sensor. These three devices were immersed in aqueous solutions of Cu(II) and the content of this metal was evaluated by emission quenching experiments. The sensor containing the highly luminescent antenna chelate of diethylenetriaminepentaacetic acid (dtpa) sensitized with Coumarin120 rendered the highest Stern Volmer constant (KSV=1.49.104 M-1) showing no leaching of the Eu(III) complex to the aqueous solution, and a reproducible value of the luminescence ratio between water and Cu(II) solution. The in-situ sensor we developed can measure the concentration of Cu(II) in aqueous media down to the ppm level by emission quenching experiments. This methodology permits a simple calibration of the sensor and an easy to use re-usable device.