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Updated: Jun 28, 2026

An Anaerobic Biosensor Assay for the Detection of Mercury and Cadmium
Published on: December 17, 2018
Simultaneous spectrophotometric determination of cadmium, copper and zinc
A M Rodriguez1, A G de Torres, J M Pavon
1Department of Analytical Chemistry, Faculty of Sciences, University of Málaga, 29071 Málaga, Spain.
Abstract:
A method for the simultaneous spectrophotometric determination of cadmium, copper and zinc based on the formation of their complexes with 1,5-bis(di-2-pyridylmethylene)thiocarbonohydrazide is proposed. The absorption curves of these complexes overlap severely in the scanning range 380-480 nm. The analyte concentrations are calculated by a least squares fit of the pure spectra to the mixture spectra. A linear determination range of 0.1-1.7 mug/ml for cadmium, 0.1-1.3 mug/ml for copper and 0.2-1.2 mug/ml for zinc were obtained. The effect of interference was studied. The method has been applied to the determination of these metal ions in various type of materials.
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