- “DETERMINATION OF CADMIUM AT ULTRA-TRACE LEVELS BY CPE-MOLECULAR FLUORESCENCE COMBINED METHODOLOGY”

TALÍO M, LUCONI M, MASI A, FERNÁNDEZ L

Mendoza. Argentina.

Congreso; XXVI Reunión Científica Anual de la Sociedad de Biología de Cuyo; 2008

Trace heavy metals are considered to be one of the main sources of pollution since they have significant effect on its ecological quality. Cadmium is very important in environmental and biological sciences; it is highly toxic even at low concentrations, causing damages to organs such as the kidneys, liver and lungs. A highly sensitive micelle-mediated extraction methodology for the preconcentration of trace levels of cadmium as a prior step to its determination by molecular fluorescence has been developed. Metal was complexed with o-phenanthroline (o-phen) and eosin (eo) in buffer Tris medium pH 7,6 and quantitatively extracted into a small volume of the surfactant-rich phase of PONPE 7.5 after centrifugation. The chemical variables affecting cloud point extraction (CPE) were evaluated and optimized. The calibration for Cd(II)/o-phen/eosina was: y = 7 109 [Cd2+] + 4,635; R2 = 0,9592; LOD: 3,90x10-3 mg L-1; LOQ: 0,013 mg.L-1. The method presents good sensitivity and selectivity and was applied to the determination of trace amounts of cadmium in water samples with satisfactory results. The proposed method is an uncommon application of CPE-luminescence to metal analyze, and comparable as for sensitivity and accuracy to atomic spectroscopies.