%0 Journal Article
%T W+Rh as permanent chemical modifier in simultaneous atomic absorption spectrometry: interference studies on As, Cd, Pb and Se determination
%A Nomura
%A Cassiana S
%A Correia
%A Paulo R. M
%A Oliveira
%A Pedro V
%A Oliveira
%A Elisabeth
%J Journal of the Brazilian Chemical Society
%D 2004
%I Sociedade Brasileira de Qu¨Şmica, SBQ
%R 10.1590/S0103-50532004000100013
%X a systematic study of na+, k+, ca2+, mg2+, cl-, no3-, so42- and po43- interference on the simultaneous atomization of as, cd, pb and se was carried out using an electrothermal atomic absorption spectrometer. the mixture 250 mg w + 250 mg rh was thermally deposited on the graphite tube platform and used as permanent chemical modifier. the compromised heating program adjustments (tp = 650&ordmc and ta = 2200&ordmc) diminished the thermal decomposition and volatilization efficiency of the interfering species during the pyrolysis step. the cl- and so42- anions caused the most severe interference, while no3- only affected the analytes' atomization when high amounts (> 27 mg) were used. the anion po43- produced a strong negative interference on the se absorbance signals. the presence of na+, k+, ca2+ and mg2+ prejudiced mainly cd, and the interference effects of cl- salts were more pronounced than no3- salts.
%K simultaneous atomic absorption spectrometry
%K interference
%K permanentchemical modifier.
%U http://www.scielo.br/scielo.php?script=sci_abstract&pid=S0103-50532004000100013&lng=en&nrm=iso&tlng=en