Atomic absorption spectrometry: general and basic principles

Atomic Absorption Spectrometry (AAS) is a method of elementary analysis of major and trace components with a limit of detection of the order of ppb. It allows the metering of metals and many inorganic materials (rocks and minerals metals and alloys ...). Its main applications are in metallurgy and in mineral chemistry.Atomic Absorption spectrometry consists in creating a plasma containing free atoms of elements to be measured in the excited state and in the ground state and in sweeping this plasma by a light beam of the same wavelength as that emitted by excited atoms. The beam intensity is measured before and after passing through the atoms in the ground state and the amount of energy absorbed is directly proportional to the number of atoms present.During this analysis the sample is brought to a high temperature most often by direct suction in a flame or atomization in a graphite furnace.