Otro
Determination of vanadium in urine by electrothermal atomic absorption spectrometry using hot injection and preconcentration into the graphite tube
Registro en:
Journal of the Brazilian Chemical Society, v. 15, n. 5, p. 676-681, 2004.
0103-5053
10.1590/S0103-50532004000500011
S0103-50532004000500011
WOS:000224958800011
2-s2.0-9644300887.pdf
2-s2.0-9644300887
Autor
Fernandes, Kelly G.
Nogueira, Ana Rita A.
Gomes Neto, José A.
Nóbrega, Joaquim A.
Resumen
In this work it was developed a procedure for the determination of vanadium in urine samples by electrothermal atomic absorption spectrometry using successive injections for preconcentration into a preheated graphite tube. Three 60 μL volumes were sequentially injected into the atomizer preheated to a temperature of 110°C. Drying and pyrolysis steps were carried out after each injection. A chemical modifier, barium difluoride (100 mg L-1), and a surfactant, Triton X-100 (0.3% v v-1), were added to the urine sample. When injecting into a hot graphite tube, the sample flow-rate was 0.5 μL s-1. The limits of detection and quantification were 0.54 and 1.82 without preconcentration, and 0.11 and 0.37 μg L-1 with preconcentration, respectively. The accuracy of the procedure was evaluated by an addition-recovery experiment employing urine samples. Recoveries varied from 96.0 to 103% for additions ranging from 0.8 to 3.5 μg L-1 V. The developed procedure allows the determination of vanadium in urine without any sample pretreatment and with minimal dilution of the sample.