Anodic-stripping voltammetry of metal complexes in non-aqueous media after extraction: determination of copper with salicylaldoxime

Abstract

The determination of copper in biological materials and ores was carried out by anodic-stripping voltammetry in non-aqueous media after its extraction with salicylaldoxime into 1,2-dichloroethane and addition to an aliquot of the extract of 5%V/V perchloric acid solution in N,N-dimethylformamide as supporting electrolyte. Different instrumental parameters were studied. The sensitivity and selectivity were considerably improved. The precision was 2.9%(n= 8) for the determination of 2 µg ml^–1 of copper and the detection limit was 15 ng ml^–1 of Cu(II). The method can be applied to the determination of other elements (Sb, Bi, Cd, Sn and Pb) at the microgram level and even the simultaneous determination of several elements after their extraction with organic reagents (8-hydroxyquinoline, benzoylphenylhydroxamic acid, sodium diethyldithiocarbamate)(Pb + Cu, Pb + Bi, Pb + Cd, Pb + Cd + Bi and Pb + Cd + Cu).