Data/hora: 19/06/2024 03:54:28

Biblioteca(s): | Embrapa Pecuária Sudeste.
Data corrente: | 12/07/2006
Data da última atualização: | 30/08/2013
Autoria: | DONATI, G. L.; NASCENTES, C. C.; NOGUEIRA, A. R. de A.; ARRUDA, M. A. Z.; NÓBREGA, J. A.
Título: | Acid extraction and cloud point preconcentration as sample preparation strategies for cobalt determination in biological materials by thermospray flame furnace atomic absorption spectrometry.
Ano de publicação: | 2006
Fonte/Imprenta: | Microchemical Journal, v.82, p.189-195, 2006.
Idioma: | Inglês
Conteúdo: | A thermospray flame furnace atomic absorption spectrometer (TS-FF-AAS) was employed for Co detennination in biological materiaIs. Cobalt presents a high atomization temperature and consequently poor sensitivity is obtained without changing its thennochemical behavior. The effect of different complexing agents on sensitivity was evaluated based on the fonnation of Co volatile compounds. A cloud point procedure was optimized for Co preconcentration for further improvement of sensitivity. Samples were treated with I moI I-I hydrochloric acid solution for quantitative extraction of Co without simultaneous extraction of Fe, since it is a strong interferent. After the extraction and preconcentration steps, a sample volume of 150 /lI was introduced into the hot Ni tube using air as carrier at a tlow-rate of 0.4 ml min- I. The best sensitivity was attained using ammonium pyrrolidinedithiocarbamate (APDC) and Triton X-114 was employed for implementation of the cloud point procedure. The detection limit obtained for Co was 2.1 /lg 1-1 and the standard deviation was 5.8% for a solution containing 100/lg I-I (n= 10). Accuracy was checked using two certified reference materiaIs (tomato leaves and bovine li ver) and results were in agreement with certified values at a 95% confidence leveI. Employing the developed procedure, Co were quantified in different biological materiaIs (plant and animal tissues).
Palavras-Chave: | Acid extraction; Cloud point extraction; Flame atomic absorption spectrometry; Thermospray; Tube in flame.
Thesaurus Nal: | cobalt.
Categoria do assunto: | --
Registro original: | Embrapa Pecuária Sudeste (CPPSE)
Exemplares: | CPPSE - (16293-1) - UPC - AP - -- - PROCI-2006.00012 - DON - 2006.00012 - DIS