Atomic absorption spectrometry (abbreviated as AAS) is a technology used for the analytical determination of trace amounts of chemical elements, mainly metals in samples of solid, liquid and gas. AAS spectrometers are widely used for the determination of heavy metals, eg. in the soil, sewage
This technology uses the fact that the atoms in the ground state can absorb radiation at a specific wavelength of the wave. Atoms are usually in the ground state. Excitation occurs after a respective portion of the energy is absorbed, characteristic for a given element (characteristic wavelengths). In this technique, as the light source lamp with the hollow cathode made of a suitable element is usually used. When electromagnetic radiation (light) passes through the atomic vapor, it is absorbed by it. Concentration of the element can be determined on the basis of the estimation of the absorption.
AAS method prior to measurement requires a calibration curve. The amount of analyte is dependent on the number of possessed hollow cathode lamp. One cathode tube is designed for one particular element.