Comparison of wet microwave digestion methods of plant materials for the determination of metals by flame atomic absorption spectrometry
Titel:
Comparison of wet microwave digestion methods of plant materials for the determination of metals by flame atomic absorption spectrometry
Auteur:
Walas, Stanisław Wojtowicz, Małgorzata Mrowiec, Halina Zegar, Waldemar
Verschenen in:
International journal of environmental analytical chemistry
Paginering:
Jaargang 84 (2004) nr. 13 pagina's 1023-1032
Jaar:
2004-11-15
Inhoud:
Microwave closed-system wet digestion procedures for plant samples were examined. Each procedure was tested with samples of tobacco and cabbage, and included digestion by the use of different acids composition, almost complete evaporation of the digest, and then dissolution of the residue in 1% nitric acid. Three microwave digestion programs that varied power, duration, and temperature were used. Closed-vessel reactions followed open-vessel reaction-delay time. Using flame atomic absorption spectrometry on the digests, four or five elements were determined to evaluate effectiveness, precision and accuracy of analytes extraction into solution. After a preliminary study of tobacco digests, the four most effective procedures were chosen, and detailed investigations were carried out on both tobacco and cabbage reference materials. Although all four of the final procedures were accurate, the most precise procedure, with the lowest errors of determination, was using reverse 'aqua regia' for tobacco and 'aqua regia' for cabbage.