Direct determination of Cr and Cu in urine samples by electrothermal atomic absorption spectrometry using ruthenium as permanent modifier (R1)

Abstract

In this study Ru, deposited thermally on an integrated platform pyrolytic graphite tube, is proposed as a permanent modifier for the determination of Cu and Cr in urine samples by electrothermal atomic absorption spectrometry. The samples were diluted 1:1 with nitric acid (1% v/v). Pyrolysis and atomization temperatures for spiked urine samples were 1,100 degrees C and 1,900 degrees C respectively for Cu, and 1,400 degrees C and 2,500 degrees C respectively for Cr. For comparison purposes, the conventional modification with Pd+Mg was also studied. The sensitivity for Ru as permanent modifier was higher for the two analytes. The characteristic masses were 7.3 and 17.7 for Cr and Cu. The detection limits (3sigma) were 0.22 and 0.32 microg/L, for Cr and Cu, respectively. Good agreement was obtained with certified urine samples for the two elements.

Comparative efficacy of platinum group metal modifiers in electrothermal atomic absorption spectrometry

“…[70]. Although analysis conditions were better in the latter case (t pyr =1500 8C, t atom =2100 8C; for permanent Ru modifier t pyr =1400 8C, t atom =2500 8C), characteristic mass for chromium was superior using a Ru modifier (7.3 pg; for Pd+Mg modifier m 0 =8.6 pg).…”

“…The comparative efficiency of permanent Ru (500 Ag) and regular Pd+Mg (15 Ag+10 Ag) modifiers for the determination of copper in urine under STPF conditions was studied by Lelis et al [70]. Although characteristic masses for copper were close in both cases (16.0 and 19.1 pg for Ru and Pd+Mg modifiers, respectively), the corresponding detection limits differed significantly (0.32 and 2.30 Ag l À1 ).…”

La préparation des matrices biologiques pour l’analyse des métaux

“…Un mélange de palladium et de magnésium sous forme de nitrates est recommandé de façon universelle comme modificateur pour le dosage du chrome et du cadmium [23] (tableau II).…”

Atomic spectrometry update. Clinical and biological materials, foods and beverages

“…Ruthenium was used as a permanent modifier in the determination of Cr and Cu in urine by ETAAS, giving better sensitivity than a Pd-Mg modifier. 92 Samples were diluted 1 1 1 with 1% v/v HNO 3 . The Ru modifier gave LODs of 0.22 and 0.32 mg l 21 for Cr and Cu, respectively.…”

“…Two groups examined different chemical modifiers for the determination of Cr in biological matrices. Lelis et al 92 used a permanent Ru chemical modifier to determine Cr and Cu in urine samples by ETAAS. Urine samples were simply diluted 1 1 1 v/v with 1% HNO 3 .…”