Studies on photochemical vapor generation of selenium

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2019
Çetmeli , Melis
Selenium is a significant trace element for human health. Selenium can be essential or toxic for human body depending on its concentration. Within the scope of this thesis, photochemical vapor generation tungsten coil atomization technique has been studied for the determination of selenium. Volatile selenium compounds were generated by exposure of UV light of the solution containing selenium and acetic acid. To increase sensitivity of photochemical vapor generation system, the technique was combined with tungsten-coil atomization. Generated volatile selenium species were trapped and atomized on the rhodium coated tungsten coil. Among Ru, Rh, Ir, Co and Pd coated tungsten coils, selenium signal was sharper, more reproducible and more sensitive with rhodium coated tungsten coil. The experimental parameters were optimized. LOD and LOQ of the technique were determined as 3.3 and 11.1 μg/L respectively. Technique was applied to selenium dietary supplements containing sodium selenite. The concentration of selenium in tablets was determined by using photochemical vapor generation tungsten-coil atomization method. The result is consistent with the certificate value given by the company. Interference from PVG-amenable elements, transition metals and earth base elementswas investigated. The most severe interference effect on the signal of Se (IV) was observed from copper.

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Citation Formats
M. Çetmeli, “Studies on photochemical vapor generation of selenium,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Chemistry., Middle East Technical University, 2019.