In flame atomic absorption spectrometry, the sample is nebulized and sucked into a burner, so that analyte elements can be atomized in a flame of a fuel gas, such as acetylene, and an oxidation gas, usually air. The burner is positioned in such a way that the flame region with the maximum atom concentration is in the ray path of the spectrometer. These atoms are able to absorb element-specific radiation. To this end, an element-specific lamp with a hollow cathode made of the element to be investigated is introduced into the ray path of an atomic absorption spectrometer with the atomization device and a detector. Depending on the concentration of the element to be determined in the sample, some of the radiation intensity of the hollow-cathode lamp is absorbed by the atoms formed. The detection system (often a photomultiplier or photodiode) measures the intensity of the non-attenuated radiation and the radiation after leaving the atomization device during the supply of a sample solution. The element concentration in the sample can then be calculated from the difference in the two intensities.
The dispersion or dilution of the sample zone can be controlled and adapted to the requirements of the analysis, by varying some operational parameters including the injected sample volume, the flow rate of carrier and reagent streams, the reaction coil length, and the inner diameter of the tubing.
