Determination of vanadium in urine by electrothermal atomic absorption spectrometry using hot injection and preconcentration into the graphite tube

• Autor(a) principal: Fernandes, Kelly G.
• Data de Publicação: 2004
• Outros Autores: Nogueira, Ana Rita A., Gomes Neto, José A. [UNESP], Nóbrega, Joaquim A.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1590/S0103-50532004000500011; http://hdl.handle.net/11449/67858
• topic: ETAAS; Hot injection; Preconcentration; Urine; Vanadium; barium derivative; barium difluoride; graphite; triton x 100; unclassified drug; vanadium; accuracy; atomic absorption spectrometry; dilution; flow rate; injection; urinalysis

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.