The atomization of cadmium in graphite furnaces

Abstract

The effect of the atomization temperature on the analysis of cadmium in graphite furnaces has been studied. A comparison of the electrothermal atomic absorption spectrometry (ETAAS) determination of total Cd in animal tissues was carried out with Zeeman effect and deuterium background corrections. A detailed study of the atomic absorption profile and background correction of cadmium, as well as the variation of absorbance values at different atomization temperatures, in both peak-height and integrated modes, has been made. The accuracy of the ETAAS determination of Cd in tissue samples, using various atomization temperatures, has also been evaluated, having found that an atomization temperature equal or higher than 1600 °C is necessary in order to obtain accurate and reproducible results. The use of low atomization temperatures, suggested in some published works, makes it possible to obtain accurate results, but the slow production of gaseous atoms of cadmium can affect the precision of the absorbance measurements and strongly affects the peak area values. On the other hand, the use of atomization temperatures higher than 2000 °C produces bad recoveries of cadmium in the analysis of certified tissue samples.