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Study of properties of UV-photochemical generation of volatile compounds od antimony
Adámková, Dominika ; Červený, Václav (advisor) ; Hraníček, Jakub (referee)
The master thesis deals with comparison of atomic fluorescence spektrometry and high resolution continuum source atomic absorption spektrometry for three methods generation of volatile compounds Antimony. In both methods of atomic antimony detection, it compares the most common chemical generation of volatile compounds (hydrides) with two alternative methods - electrochemical and UV - photochemical. The values of performance parameters for the determination of Sb(III) and Sb(V) were determined for all the above combinations. In the case of chemical generation, a surprisingly almost four times higher limit of detection of Sb(III) was found in connection with AFS detection than AAS detection. The final part was devoted to UV - photochemical vapor generation, with AAS detection for Sb(III) reaching limit of detection 4,96 ppb, for Sb(V) 8,63 ppb. Although UV - photochemical generation of volatile antimony compounds did not reach such performance parameters as chemical or electrochemical generation, it was observed that the sensitivity of antimony determination increased greatly when introducing oxygen into the apparatus. The interference study also found a significant positive effect of Fe(II) on the generation efficiency, and this modification partially persisted without further introduction of these...
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Novel Approaches to the Application of Electrochemical Volatile Compounds Generation in Spectrometric Methods
Červený, Václav ; Rychlovský, Petr (advisor) ; Spěváčková, Věra (referee) ; Komárek, Josef (referee)
Various possibilities for the use of electrochemical generation of volatile compounds for the determination of trace and ultratrace quantities of elements using atomic absorption spectrometry and optical emission spectrometry, respectively, were studied in this work. The Thesis is divided into four thematic sections. Electrochemical cold mercury vapor generation is common to the first two parts. The third part is devoted to electrochemical generation of the volatile form of cadmium and the last part deals with the use of the electrochemical hydride generator as a derivatization unit for speciation analysis of arsenic compounds. The optimization of each individual determination was carried out including, for example, various designs of the generator of volatile compounds (forms) of the analyte, the changes in the design of the gas-liquid separator, optimization of the concentration and the flow rate of all the solutions and the carrier gas. However, the value of the electric current employed was the most important parameter. In the first section, the in-situ trapping system of the cold mercury vapor generated in the graphite furnace (with the inner surface covered with a gold foil) of the atomic absorption spectrometer was also designed and optimized. The absolute limit of detection, 80 pg, was...
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Speciation analysis of arsenic-glutathione complexes by ion-pairing HPLC-ICP-MS
Zušťáková, Veronika ; Matoušek, Tomáš (advisor) ; Červený, Václav (referee)
The thesis has focused on the separation of arsenic-glutathione species using ion-pairing high performance liquid chromatography with detection by inductively coupled plasma mass spectrometry. Species were separated on chromatographic column Prodigy ODS (3) using an aqueous mobile phase containing 4.7mM tetrabutylammonium hydroxide (TBAH), 2mM malonic acid and 4% methanol at pH 5.85 in the isocratic mode. Simple arsenic species - arsenite (iAsIII), arsenate (iAsV) monomethylarsenic acid (MAsIII), monomethylarsenous acid (MAsV), dimethylarsenic acid (DMAsIII) and dimethylarsenous acid (DMAsV), which served as arsenic standards to determine retention times, were successfully separated under these conditions. Arsenic-glutathione complexes As(GS)3, MAs(GS)2 and DMAs (GS) were not successfully separated. These complexes provided peaks of simple arsenic species. Peak broadening was observed in the first analysis of As(GS)3 and MAs(GS)2 complexes, which disappeared in subsequent analyses. This broadening probably represents a residual of glutathion complex which disintegrated to single species. Powered by TCPDF (www.tcpdf.org)
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Determination of acetylsalicylic acid by sequential injection analysis with spectrophotometric detection
Vrtalová, Martina ; Hraníček, Jakub (advisor) ; Červený, Václav (referee)
This diploma thesis is focused on the determination of acetylsalicylic acid using two methods of flow analysis; Flow Injection Analysis (FIA) and Sequential Injection Analysis (SIA) with spectrophotometric detection. The principle of determination is based on the acetylsalicylic acid decomposition to give salicylic ion. This ion reacts subsequently with Fe3+ ion in acidic solution leading to colored chelating complex Fe(SAL)+ . The increase of absorbance of this complex in its absorption maximum was used for analytical determination. Sodium salicylate (sodium salt of acetylsalicylic acid) was used as a standard substance. In the first part of this work, experimental arrangement for flow injection analysis was setup. Continuously the optimization of experimental conditions of acetylsalicylic acid determination was performed to obtain the higher sensitivity. Under the optimal conditions the basic characteristics of determination was measured. In the second part of this work, the commercial experimental instrument FIA Lab 3500 was used for determination. Optimization of experimental conditions and basic characteristic of determination by sequential injection analysis was performed as well. Developed methods for determination of acetylsalicylic acid with selected technique were verified by analyzing...
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Analysis of Historical Pharmaceutical Preparations of Caffeine and Santonin.
Nováková, Lucie ; Nesměrák, Karel (advisor) ; Červený, Václav (referee)
Historical pharmaceutical preparations of caffeine and santonin were analyzed by mass spectrometry, the sample of caffeine was quantified by spectrophotometry, the sample of santonin was quantified by acid-base titration. In the analyzed historical injection solution "Coffeinum natriosalicylicum" (dated circa 1945) was determined 110 ± 1 % of the declared amount of caffeine and 94.33 ± 0.02 % of the declared amount of sodium salicylate. There were observed neither degradation products of caffeine nor sodium salicylate. The content of santonin in the historical sample (dated prior 1918) was determined by titration to 104 ± 4 %, sample was pure santotnin with no additions. No degradation products of santonin was observed. The analyzed samples were stable for more than seventy, ninety resp., years of storage.
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Determination of cadmium and copper in bood of great tits
Adamová, Simona ; Hraníček, Jakub (advisor) ; Červený, Václav (referee)
EN Monitoring of the environment is one of the most important activities nowadays. This monitoring includes, for example, monitoring the concentration levels of heavy metals in organisms with a defined relationship to the environment. Great tit (Parus major) was evaluated as a suitable indicator of the environment especially for its abundance and presence near human settlements. The target of this bachelor thesis is to determine cadmium and copper in dried blood samples of these birds from several parts of Europe. All samples were prepared using microwave digestion and analyzed using the inductively coupled plasma mass spectrometry, which is known for its ability to determine simultaneously metals in biological samples even at very low concentrations. Key words Inductively coupled plasma mass spectrometry, heavy metals, copper, cadmium, great tit, blood
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