Electrochemical determination of arsenic in natural waters using carbon fiber ultra-microelectrodes modified with gold nanoparticles.
Talanta
; 166: 198-206, 2017 May 01.
Article
em En
| MEDLINE
| ID: mdl-28213223
We have developed an anodic stripping voltammetry method that employs carbon fiber ultra-microelectrodes modified with gold nanoparticles to determine arsenic in natural waters. Gold nanoparticles were potentiostatically deposited on carbon fiber ultra-microelectrodes at -0.90V (vs SCE) for a time of 15s, to form the carbon fiber ultra-microelectrodes modified with gold nanoparticles. Cyclic voltammetry, electrochemical impedance spectroscopy and scanning electron microscopy coupled to an X-ray microanalysis system were used to check and confirm the presence of gold nanoparticles on the carbon fiber ultra-microelectrodes. Arsenic detection parameters such as deposition potential and deposition time were optimized allowing a detection range between 5 to 60µgL-1. The developed modified electrodes allowed rapid As determination with improved analytical characteristics including better repeatability, higher selectivity, lower detection limit (0.9µgL-1) and higher sensitivity (0.0176nAµgL-1) as compared to the standard carbon electrodes. The analytical capability of the optimized method was demonstrated by determination of arsenic in certified reference materials (trace elements in water (NIST SRM 1643d)) and by comparison of results with those obtained by hydride generation atomic absorption spectrometry (HG-AAS) in the determination of the analyte in tap and well waters.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Arsênio
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Poluentes Químicos da Água
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Carbono
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Água
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Eletroquímica
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Nanopartículas Metálicas
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Ouro
Idioma:
En
Revista:
Talanta
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Equador
País de publicação:
Holanda