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Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies
Published on: July 1, 2016
A preconcentration procedure for the determination of cadmium in biological material after on-line cloud point
Patrícia Xavier Baliza1, Luiz Augusto Martins Cardoso, Valfredo Azevedo Lemos
1Universidade Federal do Espírito Santo, Departamento de Ciências Matemáticas e Naturais, Rodovia BR 101 Norte, Km 60, Litorâneo, 29932-540, São Mateus, Espírito Santo, Brazil.
Abstract:
In this paper, a method involving on-line preconcentration with cloud point extraction for the determination of cadmium in biological samples is presented. The procedure is based on the sorption of micelles containing Cd(II) ions and the reagent 4-(5'-bromo-2'-thiazolylazo)orcinol (Br-TAO) in a minicolumn packed with polyester. The surfactant Triton X-114 was used in the formation of micelles. After sorption, the Cd(II) ions were desorbed from the minicolumn with acid eluent and determined by flame atomic absorption spectrometry. Parameters influencing the cloud point extraction were studied. The method showed a detection limit of 0.5 μg l(-1) and an enhancement factor of 27. The accuracy was tested by determination of cadmium in certified reference materials (spinach leaves 1570a and tomato leaves 1573a) from the National Institute of Standards and Technology.
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