Study of chemical modifiers for the determination of chromium in biological materials by tungsten coil electrothermal atomic absorption spectrometry

Autor: José Y. Neira, Margarita Darder, Joaquim A. Nóbrega, Carlos G. Bruhn, M. I. Guzmán
Rok vydání: 1999
Předmět:
Zdroj: Fresenius' Journal of Analytical Chemistry. 364:273-278
ISSN: 1432-1130
0937-0633
DOI: 10.1007/s002160051337
Popis: The determination of Cr in digest solutions of mussels and non-fat milk powder by tungsten coil electrothermal atomic absorption spectrophotometry (TC-ETAAS) is affected by interferences. This study reports a critical evaluation of chemical modifiers that could be employed to correct these interferences. The chemical modifiers tested were: Mg [as Mg(NO3)2], Pd [as Pd(NO3)2], NH4NO3, ascorbic acid, and mixtures of these compounds. The less effective modifier was NH4NO3. The best effects, considering thermal stabilization and sensitivity, were obtained in mixtures of ascorbic acid plus Mg. Chromium was determined by TC-ETAAS in certified reference materials of mussels and non-fat milk powder, and results were comparable with those obtained by graphite furnace atomic absorption spectrophotometry (GFAAS).
Databáze: OpenAIRE