Computer aided signal analysis in electrothermal atomization-atomic absorption spectrometry—accuracy and precision: peak height vs peak area

Abstract

A systematic approach to the question of the height or area calculation in electrothermal atomization-atomic absorption spectrometry (ETA-AAS) is given. Points studied are the real time sampling, power spectrum, temperature and the chemical composition of the sample. It turned out that generally the height gives somewhat more precise results for the furnace studied, the Varian CRA 90, but the difference with the area measurements was not dramatic. A far better approach is the measurement of the height multiplied by the peak time. Precision here can be as good as 1–2 % RSD on a concentration level of 0.3 μg 1 , while a characteristic mass of 0.041 μg is obtained. This shows how good ETA-AAS can be. However, with chemical more complex elements as lead, the mentioned precision will only be reached after sample destruction or matrix modification.