Anales de la Asociación Química Argentina
Print version ISSN 0365-0375
PELLERANO, R.G. et al. Determination of lead in the Parana River by solid phase spectrophotometry. An. Asoc. Quím. Argent. [online]. 2006, vol.94, n.4-6, pp. 83-90. ISSN 0365-0375.
The paper proposes a procedure for determination of lead in water samples by solid phase spectrophotometry (SPS). It is based on the reaction of Pb(II) ion with 2-(5-Bromo-2-pyridylazo)-5-(diethylamino)phenol (5-Br-PADAP) immobilized on an anion-exchange resin, that gives rise to a coloured complex, whose absorbance is measured directly at the solid phase. The method provides a detection limit of 2.4 µg L-1 and a sample throughput of 2 h-1. The relative standard deviation (R.S.D.) was 1.7% for a Pb(II) concentration of 10.0 µg L-1. The calibration graph obtained was linear with a correlation coefficient of 0.9995, in the range from the detection limit up to at least 100 µg L-1. This method was successfully applied to the determination of Pb(II) in natural superficial waters from the Parana River in Argentina.