Determination of tin in marine sediments by slurry sampling atomic absorption spectrometry with electrothermal atomization using a permanent modifier

Abstract

Slurry sampling atomic absorption spectrometry with electrothermal atomization was used for the determination of tin in marine sediments. A mixture of 4 μg of iridium and 40 μg of tungsten and 12 μg of niobium alone were used as permanent modifiers. Suspensions were prepared in 7% nitric acid. The influence of amounts of tungsten on iridium removal from graphite tubes modified by iridium and the mechanism of atomization of tin in slurries were studied in detail. The effect of the amount of added iridium, tungsten and niobium on the analytical signal, and of the soil matrix on the background signal is described. In order to prevent interferences by sulfur compounds, barium chloride was added as a matrix modifier. Calibration was performed directly using aqueous standards. The analysis of certified reference materials confirmed the reliability of the approach. The precision and accuracy of the determination of tin in sediments by this method is acceptable.