Determination of Monomethylarsenous Acid by Hydride Generation - Gas Phase Molecular Absorption Spectrometry
- Sanz-Asensio, J. 1
- Martínez-Soria, M.T. 1
- Plaza-Medina, M. 1
- Pérez Clavijo, M. 1
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1
Universidad de La Rioja
info
ISSN: 0003-2670
Year of publication: 1999
Volume: 381
Issue: 2
Pages: 331-339
Type: Article
More publications in: Analytica Chimica Acta
Abstract
This paper presents a method for the determination of methylarsenous acid which is converted into gaseous methylarsine by adding a sodium tetrahydroborate(m) solution. The generated arsine is collected in a liquid nitrogen cryogenic trap. This is revolatilized and driven to the quartz flow cell and measured by gas phase molecular absorption spectrometry with diode array detection. The spectra obtained over a wide range of wavelengths allows multivariate calibration. The parameters affecting the production and collection of the arsines are studied. The detection limit, (6 x SD of blank) = 2.8 ng ml-1 and the relative standard deviation (n = 10) at 28 ng ml-1 was 5.3%. An interference study is made.