Study and comparison of several chemical modifiers for selenium determination in human serum by Zeeman electrothermal atomic absorption spectrometry

Abstract

The conditions for the determination of selenium in human serum samples using a Zeeman graphite furnace with integrated platform graphite tubes are established. Performance characteristics including background signal, analytical signal and the effects on the platform of several chemical modifier solutions of varying concentrations were studied and compared. Ashing and atomising curves were obtained for each chemical modifier solution. The optimal measuring conditions were established for each modifier. The most appropriate modifier was then chosen on the basis of the sensitivity and detection limits for the determination of selenium in serum. The method was validated by analysing a Seronorm™ Trace Element (Oslo, Norway) quality control serum (78 μg l −1) and a ‘Second-Generation’ freeze-dried human serum, from the University of Ghent (1.05 μg g −1 dry-weight). The values obtained were 81.5 ± 1.8 μg Se l −1 and 1.08 ± 0.02 μg Se g −1, respectively. These results are consistent with the certified values of both reference materials.