Arabadji M. Atomic absorption determination of copper, zinc, lead, cadmium and selenium in biological fluids and foodstuffs using graphite filter furnace atomizer with carbon tread

The thesis is devoted to the study of the main features, characteristics and capabilities of a longitude heating furnace with a graphite filter furnace and carbon thread, and the creation on the basis of the obtained data of fairly simple and reliable methods for direct atomic-absorption determination of Cu, Zn, Pb, Cd and Se in blood, urine, saliva, breast milk, wines, natural waters, vegetable and animal oils and fats during their evaporation in the presence of a universal chemical modifier (a mixture of Pd and Mg nitrates). A heating model for the «GRAFIT-2» atomizer is proposed, taking into account heat loss due to transfer to protective gas – argon. The analytical characteristics of the electrothermal atomic-absorption determination of Cd, Pb, Cu, Se and Zn are established when they evaporate from the surface of a graphite filter furnace and carbon thread, including in the presence of a chemical modifier. The effect of the main mineral and organic components of analyzed materials on the relative absorption of Zn, Cu, Pb, Cd and Se atoms is considered. It is noted that evaporation of the analyzed solutions with graphite filter furnace and carbon thread in the presence of a chemical modifier almost completely eliminates non-selective absorption of light, as well as the influence of the determination of Zn, Cu, Pb, Cd and Se on the results of ET AAS up to 1,5 g/l of the basic mineral and up to 15-200 g/l organic components of some biological fluids (blood, urine, saliva, breast milk) and food products (wine, natural waters, vegetable and animal oils and fats). Was developed the complex of sensitive, simple and reliable methods of direct analysis of blood, urine, saliva, breast milk, wines, natural waters, vegetable and animal fats and oils samples.