Tungsten permanent chemical modifier for fast estimation of Se contents in soil by graphite furnace atomic absorption spectrometry


Autoria(s): Rosa, C. R.; Freschi, GPG; De Moraes, M.; Neto, JAG; Nobrega, J. A.; Nogueira, ARA; Sacramento, L. V.
Contribuinte(s)

Universidade Estadual Paulista (UNESP)

Data(s)

20/05/2014

20/05/2014

02/07/2003

Resumo

A tungsten carbide coating on the integrated platform of a transversely heated graphite atomizer was used as a modifier for the direct determination of Se in soil extracts by graphite furnace atomic absorption spectrometry. Diethylenetriaminepentaacetic acid (0.0050 mol L-1) plus ammonium hydrogencarbonate (1.0 mol L-1) extracted predominantly available inorganic selenate from soil. The formation of a large amount of carbonaceous residue inside the atomizer was avoided with a first pyrolysis step at 600 degreesC assisted by air during 30 s. For 20 muL of soil extracts delivered to the atomizer and calibration by matrix matching, an analytical curve (10.0-100 mug of L-1) with good linear correlation (r = 0.999) between integrated absorbance and analyte concentration was established. The characteristic mass was similar to63 pg of Se, and the lifetime of the tube was similar to750 firings. The limit of detection was 1.6 mug L-1, and the relative standard deviations (n = 12) were typically <4% for a soil extract containing 50 mug of L-1. The accuracy of the determination of Se was checked for soil samples by means of addition/recovery tests. Recovery data of Se added to four enriched soil samples varied from 80 to 90% and indicated an accurate method.

Formato

3920-3923

Identificador

http://dx.doi.org/10.1021/jf0212439

Journal of Agricultural and Food Chemistry. Washington: Amer Chemical Soc, v. 51, n. 14, p. 3920-3923, 2003.

0021-8561

http://hdl.handle.net/11449/7672

10.1021/jf0212439

WOS:000183824200003

Idioma(s)

eng

Publicador

Amer Chemical Soc

Relação

Journal of Agricultural and Food Chemistry

Direitos

closedAccess

Palavras-Chave #selenium #soil #diethylenetriaminepentaacetic acid #tungsten permanent modifier #GFAAS
Tipo

info:eu-repo/semantics/article