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Determination of Mercury in Hair by Atomic Fluorescence Spectrometry
Šandlová, Petra ; Červený, Václav (advisor) ; Hraníček, Jakub (referee)
The functionality of PS Analytical's Millenium Merlin Satellite external module to the PSA Millenium Excalibur atomic fluorescence spectrometer has been demonstrated on real samples. Hair was selected as real samples. In the first part, several extraction procedures were tested to obtain the highest response. The best results were obtained by the extraction method with TMAH and HCl in FIA-UV-PVG- AFS mode. In the next part, an attempt was made to optimize the conditions for the separation of mercury speciation, namely Hg2+ and MetHg. The optimized parameters were: the percentage of organic component in the mobile phase, the pH of the mobile phase, the flow rate of the added mobile phase per column, and the flow rate of the added 0.050M HCl per column. After this stage, 3 more extraction procedures were tested: extraction using L-cysteine with HCl, extraction using PDTC and extraction using DEDTC. However, none of the extraction procedures was better than the extraction method with TMAH and HCl. Despite the optimization of the method, the speciation of Hg in the hair samples failed because the chromatograms obtained did not match (even in retention times) those obtained for the mixture of standards with the mobile phase extraction reagents. Subsequently, the conditions for the determination of total...
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Speciation Analysis of Selected Mercury Compounds Using HPLC, UV-Photochemical Cold Mercury Vapor Generation and its AAS Detection
Linhart, Ondřej ; Červený, Václav (advisor) ; Spěváčková, Věra (referee)
The mercury occurs in the environment in a variety of forms. Mercury compounds can be found in the soil, atmosphere, water and living organisms. Although some of the mercury substances are very toxic, they are often used in various sectors of industry, agriculture and medicine. Mercury compounds differ in their toxicity, so it is necessary to do speciation analysis. The aim of this diploma thesis was to develop and validate a new analytical method for the determination of mercury compounds in different samples. This method involves the combination of high performance liquid chromatography, UV-photochemical cold vapor mercury generation and atomic absorption spectrometry. Effective separation of mercury(II), methylmercury(I), ethylmercury(I) and phenylmercury(I) ions and subsequent comparable efficient of mercury cold vapor generation from all of forms was achieved using these techniques. The reached detection limits were 8 µg l-1 , 31 µg l-1 , 16 µg l-1 and 38 µg l-1 . At the end of experimental work, the proposed method of RP-HPLC-UV-CVG- QTAAS was used for the determination of mercury compounds in real samples (fish tissue and water samples: Labe, Vltava and tap water) and in certified reference materials (DORM-3 and DOLT-4). Several methods for extraction of mercury species from solid samples...
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Extraction of Selected Mercury Compounds from Real Samples for Speciation Analysis Employing RP-HPLC-UV-CVG-QTAAS
Kolorosová, Alžběta ; Červený, Václav (advisor) ; Kratzer, Jan (referee)
The extraction of mercury species (methylmercury, ethylmercury, phenylmercury and inorganic mercury(II)) from fish tissue, its determination by reverse phase HPLC, UV-photochemical generation of cold vapour, and detection by atomic absorption spectrometry is described in this work. Various extraction agents and digestion methods were compared in order to find the best alternative. The mixture of 6.25% tetramethylammonium hydroxide and 0.05 mol·l-1 hydrochloride acid was chosen as the best extraction agent. In addition to the high extraction efficiency, the solution involved positively not only UV-photochemical generation, but also separation of observed species. On the contrary, the poor repeatability was achieved with the microwave-assisted digestion due to the proved sorption of mercury species on the Teflon vessels. Therefore, the extraction by high temperature (50-60 řC) in glass bottles was preferred. The results of the determination of the mercury species after the extraction from the real samples were compared to the outcomes obtained by AMA 254. The proposed extraction technique together with the RP-HPLC-UV-CVG-QTAAS is suitable for the speciation analysis of mercury.
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Speciation Analysis of Selected Mercury Compounds Using HPLC, UV-Photochemical Cold Mercury Vapor Generation and its AAS Detection
Linhart, Ondřej ; Červený, Václav (advisor) ; Spěváčková, Věra (referee)
The mercury occurs in the environment in a variety of forms. Mercury compounds can be found in the soil, atmosphere, water and living organisms. Although some of the mercury substances are very toxic, they are often used in various sectors of industry, agriculture and medicine. Mercury compounds differ in their toxicity, so it is necessary to do speciation analysis. The aim of this diploma thesis was to develop and validate a new analytical method for the determination of mercury compounds in different samples. This method involves the combination of high performance liquid chromatography, UV-photochemical cold vapor mercury generation and atomic absorption spectrometry. Effective separation of mercury(II), methylmercury(I), ethylmercury(I) and phenylmercury(I) ions and subsequent comparable efficient of mercury cold vapor generation from all of forms was achieved using these techniques. The reached detection limits were 8 µg l-1 , 31 µg l-1 , 16 µg l-1 and 38 µg l-1 . At the end of experimental work, the proposed method of RP-HPLC-UV-CVG- QTAAS was used for the determination of mercury compounds in real samples (fish tissue and water samples: Labe, Vltava and tap water) and in certified reference materials (DORM-3 and DOLT-4). Several methods for extraction of mercury species from solid samples...
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