Determination of As(III) in nonacidified groundwater samples for inorganic speciation analysis using flow injection hydride generation atomic absorption spectrometry

A flow injection system coupled to hydride generation atomic absorption spectrometry with heated quartz tube atomizer was employed for the selective determination of As(III) in real groundwater samples under nonacidic conditions. The use of low-acidity conditions was carefully evaluated in order to...

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Detalles Bibliográficos
Autores: Sigrist, Mirna Edit, Beldomenico, Horacio Ramon, Tudino, Mabel Beatriz
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/71536
Acceso en línea:http://hdl.handle.net/11336/71536
Access Level:acceso abierto
Palabra clave:Arsenic Speciation
Atomic Absorption Spectrometry
Flow Injection
Hydride Generation
Nonacidified Water Samples
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descripción
Sumario:A flow injection system coupled to hydride generation atomic absorption spectrometry with heated quartz tube atomizer was employed for the selective determination of As(III) in real groundwater samples under nonacidic conditions. The use of low-acidity conditions was carefully evaluated in order to minimize the interconversion of redox arsenic species. The As(III) hydride was generated using 0.1 mol L-1 HCl as carrier solution and 0.2% (m/v) NaBH4 in 0.025% NaOH as the reductant. A coil reaction larger than the used one for higher acidity conditions (480 mm instead of 115 mm) was selected. The generated hydride was transported to the atomizer by a nitrogen flow of 75 ml min-1. The main parameters that influenced the signal intensity and shape were studied. Under the best found experimental conditions, a detection limit (3σ) of 1.0 μgL-1 As(III) was obtained for a 500 μl sample volume. The analytical recovery ranged between 90% and 98%. In addition, the total inorganic arsenic concentration in the samples was determined on sample aliquots acidified with concentrated HCl and prereduced with 5% (m/v) KI-5% (m/v) C6H8O6 solution. HCl 1.2 mol L-1 as carrier solution, NaBH4 0.2% (m/v) as reductant, and a nitrogen flow rate of 75 ml min-1 were used in this case. The concentration of As(V) was calculated by difference between the total inorganic arsenic and As(III) concentrations. © Taylor & Francis Group, LLC.