Chronopotentiometric stripping analysis using gold electrodes, an efficient technique for mercury quantification in natural waters
Nenhuma Miniatura disponível
Data
2005-05-01
Autores
Augelli, M. A.
Munoz, RAA
Richter, E. M.
Gouveia, A.
Angnes, L.
Título da Revista
ISSN da Revista
Título de Volume
Editor
Wiley-Blackwell
Resumo
This paper proposes a simple methodology for mercury quantification in natural water by stripping chronopotentiometry at constant current, using gold (film) electrodes constructed from recordable CDs in stationary cell. The proposed method allows the direct measurement of labile mercury in natural waters. To quantify total mercury, a robust and low cost UV irradiation system was developed for the degradation of organic constituents of water. The proposed system presents such advantages as excellent sensitivity, low cost, versatility, and smaller dimensions (portability for on-field applications) when compared with other techniques (ICP, GFAAS, fluorimetry) traditionally utilized for mercury quantification. A large linear region of responses was observed, situated over the range 0.02 - 200 μ g L-1. Various experimental parameters were optimized and the system allowed quantifications in natural samples, with detection limit of 8 ng L-1 and excellent reproducibility (RSD of 1.4% for 48 repetitive measurements using a 10 μ g L-1 mercury solution). Different metal ions were evaluated, including copper, as possible interferences on stripping mercury signals. Applications of the new method were demonstrated for the analysis of certified and groundwater samples spiked with a known amount of mercury and for the quantification of methylmercury in synthetic oceanic water, originally utilized for fishes contamination experiment.
Descrição
Palavras-chave
mercury, chronopotentiometry, stripping analysis, gold electrodes, CDtrodes, groundwater, methylmercury, UV degradation
Como citar
Electroanalysis. Weinheim: Wiley-v C H Verlag Gmbh, v. 17, n. 9, p. 755-761, 2005.