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Preconcentration of Trace Analytes on Modified Sorbents and their Determination on Waters
Holubová, Zuzana ; Čelechovská, Olga (referee) ; Holoubek,, Ivan (referee) ; Otruba,, Vítězslav (referee) ; Sommer, Lumír (advisor)
The work has been focused on the preconcentration techniques for determination of 9Be, 51V, 59Co, 60Ni, 89Y, 111Cd, 208Pb, 232Th and 238U on the modified sorbents, all measurements were performed on ICP-MS. The instrument setup was optimized. The solution of internal standard (200 µg•l-1) was used during all measurements. The internal standard were chosen as follows: 6Li for 9Be, 45Sc (51V), 72Ge (59Co, 60Ni, 89Y), 103Rh (111Cd), 209Bi (206Pb, 207Pb, 208Pb, 232Th and 238U). Another parameters such as influence of mineral acids (HCl, HNO3), surfactant (Septonex®, Zephyramin, Ajatin, Brij 35 and Sodium dodecyl sulphate) and organic reagents (Ammonium pyrrolidinedithiocarbamate, 8-Hydroxyquinoline-5-sulphonic acid, 1,2-Dihydroxyanthraquinone-3-sulphonic acid and 4-(2-Pyridylazo)resorcinol) and the effect of some matrix components on intensity of instrument signal determination was investigated. For preconcentration polar Silicagel and modified nonpolar Silicagels (Silicagel-C18, C8 nad Phenyl) were used. Another experimantal part was dedicated to preconcentration on nonpolar Amberlite XAD-16 and Strata SDB-L and intermediately polar sorbent Amberlite XAD-7. Recoveries of sorption process were observed in the presence of all testing types of surfactants in certified concentration 5•10-4 mol•l-1. Surfactants were always applied in the conditioning step. The suitable combinations of surfactant and organic reagent were tested for increasing of recoveries of analytes. Testing organic reagents were added in five times mass excess againts concentration of analytes, the concentration of the organic reagents was 900 µg•l-1. The organic reagent was always added to the solution for preconcentration before this solution was led on the sorbent. The composition and a necessary volume of elution mixture for quantitative elution were tested, too. Only one sorbent was chosen from each group of sorbents with similar properties. The chosen sorbent showed the best recoveries in majority of target analytes. The highest recoveries from silica-group was reached for Silicagel-C18, from nonpolar Amberlite was chosen Strata SDB-L and intermediately polar Amberlite XAD-7. The influence of some matrix components (anionts and cations) on recoveries of analytes was investigated for chosen sorbent. The optimized process was applied on real samples of nature water and industry water. In experimental part all analytes are marked as specific izotopes, which were measured by ICP-MS. Of course, all izotopes of analytes undergo preconcentration techniques.
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Analysis of chemotherapeutics in extracellular vesicles
Kožnarová, Simona ; Hložková, Michaela (referee) ; Vašinová Galiová, Michaela (advisor)
Extracellular vesicles are a newly discovered way of cell-to-cell communication. The issue is still significantly unexplored, especially in the case of cancer. The goal of this pilot study was to attempt to detect platinum contained in extracellular vesicles by ICP-MS. In this study, samples of ovarian cancer cell lines treated with platinum derivatives, a type of chemotherapeutic drug, were used. This method was proved as able to detect platinum, even as able to determine its concentration reliably. The quantity of platinum in vesicles was around 1–2 % of the total platinum added to the system. The results varied according to the used platinum derivative, the cell line and the number of cells releasing the vesicles. Most platinum was determined in vesicles of the SK-OV-3 line, which is naturally resistant to this treatment, for all platinum derivatives. From these results it can be concluded that the use of ICP-MS is also advisable for additional research on this issue.
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Preconcentration Techniques for Determination of Uranium Using the Modified Sorbents.
Moos, Martin ; Řehůřková, Irena (referee) ; Kanický, Viktor (referee) ; Kráčmar, Stanislav (referee) ; Sommer, Lumír (advisor)
The work has been focused on the preconcentration techniques for determination of uranium on the modified sorbent, with the final use of ICP-OES and ICP-MS. First ICP-OES at a wavelength of 385.958 nm was used for determination of uranium. Parameters were optimized and the effect of mineral acids (HCl, HNO3), tensides (Septonex, Ajatin) and organic reagents like (4-(2-pyridylazo)resorcinol, ammonium pyrrolidinedithiocarbamate, 8-hydroxyquinoline-5-sulphonic acid and 1,2-dihydroxyanthraquinone-3-sulphonic acid) was observed. For ICP-MS an isotope 238U was chosen. As an internal standard 209Bi (200 ?g•l-1) was used. Modified silica gel was used (Silicagel tethered with C18, C8 alkyls and phenyl) and two types of Amberlite XAD 4 and XAD 16 for the preconcentration of uranium (VI). Commercially produced Amberlite was modified as follows: Drying at 100 °C (24 hours), milled, minced sorbent was selected and fractionated to particles size ranging from 0.32 to 0.63 ?m and finally activated in methanol. The deionised water and Septonex (5•10-3 mol•l-1) at pH 8 were used for Amberlite conditioning. The optimal sorption of uranium (VI) proceeded at pH 8 in the presence of 4-(2-pyridylazo)resorcinol or ammonium pyrrolidinedithiocarbamate with Amberlite XAD-16 moreover with 1,2-dihydroxyanthraquinone-3-sulphonic acid. All organic reagents have mass concentration five time larger than uranium . For the elution of uranium the mixture of 1 mol•l-1 HNO3 with acetone (ratio of 1:1) was used. Acetone was evaporated and the final analysis performed using ICP-OES. The preconcentration of uranium (VI) using Silicagel-C18 conditioning was performed with ethanol, deionised water and Zephyraminu (5•10-4 mol•l-1) at pH 8. For the Silica-C8 and Silicagel-Phenyl the same conditioning procedure without zephyramin was used. Silica-C18 had the highest sorption efficiency with 1,2-dihydroxyanthraquinone-3-sulphonic acid, Silicagel-C8 with ammonium pyrrolidinedithiocarbamate and Silicagel-Phenyl with 8-hydroxyquinoline-5-sulfonic acid, all organic reagents have mass concentration five time larger than uranium concentration. As an optimal elution mixture acetone and ethanol (ratio of 1:1) in the presence of 1 mol•l-1 HCl was evaluated. Acetone and ethanol was evaporated and the final analysis was performed using ICP-MS. Silicagel-C18 was evaluate as the most effective in the presence of zephyramin and 1,2-dihydroxyanthraquinone-3-sulphonic acid. Sorption was also tested in the presence of 20 ?g•l-1 microelements (Be, V, Co, Ni, Y, Pb, Th, Cd) and in the presence of a defined concentrations of K, Na, Ca, Mg, Al and Fe. Direct analysis of uranium was carried out on samples of water from the river Ploucnice and Turonian aquifers containing uranium, 3,5 and 19,3 ?g•l-1. Different type of water required preconcentration of uranium (VI) on Silica-C18 in the presence of 1,2-dihydroxyanthraquinone-3-sulphonic acid and zephyramin. The analysis results gave statistically satisfactory results, which were confirmed using standard addition of 20 ?g•l-1.
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Study of geographical authenticity of moravian red wine
Bidmonová, Karolína ; Punčochářová, Lenka (referee) ; Pořízka, Jaromír (advisor)
This bachelor thesis discusses the possibility of using analytical methods to determine the elemental profile of wine and to detect phenolic substances in wine. The theoretical part describes the Czech and Moravian subregions, chemical composition of wine, authenticity and methods of assessing the authenticity of wine. The next part contains a brief description of the analytical methods that were used in the experimental part. The experimental part deals with the determination of the elemental profile of wine by mass and optical emission spectrometry, the determination of phenolic substances by high performance liquid chromatography, the determination of antioxidant activity and the total content of phenolic substances. For the purpose of classifying wine samples into groups, multidimensional statistical methods (cluster analysis, principal component analysis, analysis of variance and discriminant analysis) were used to separate the groups according to geographical origin.
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Possibilities of determining the origin of the wine from the element composition
Škařupa, Přemysl ; Gregor,, Tomáš (referee) ; Diviš, Pavel (advisor)
The aim of this diploma thesis was to evaluate the possibility of determining the origin of the wine on the basis of elemental composition. For this purpose an analysis of major and minor elements was accomplished in selected varieties of wines. In total, 48 parameters for six wine subregions in Bohemia and Moravia was determined and used. The sum of 35 parameters represented the concentration of selected elements and other 13 parameters were created from the measured values. The concentration of elements was determined by inductively coupled plasma mass spectrometry (ICP-MS). For the purpose of classification of samples into groups multivariate statistical methods were used. The measured data set was firstly separated using analysis of variance (ANOVA) and discriminant analysis (DA). It has been proved that the selected variables influence the distribution of wines into categories according to their geographic location. Canonical discriminant analysis, principal component analysis (PCA) and cluster analysis has been used for graphical projection. Simultaneously the model based on our analysis was created to enable classify an unknown sample of wine according to the origin.
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Platinum group elements in waste and surface waters
Novotný, Matěj ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This assignment provides a detailed description of platinum metals, their occurrence in surface and waste water and their determination options. Currently, platinum metals are widely used in the automotive industry as a part of a catalyst, as well as in medicine and jewelery. Release of these metals in pure form and the form of oxides leads to their subsequent accumulation, which directly affects fauna and flora. Due to that, the living conditions and health status of some organisms are petting worse.
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Determination of selected metals in fruit squashs
Drobilová, Marcela ; Vránová, Dana (referee) ; Diviš, Pavel (advisor)
The theoretical part of the thesis deals with the technology of fruit juices production and characteristics of the known varieties of elderberry. There are also summarized available information on the presence and properties of minerals in food. In the practical part of the thesis 17 different varieties of elderberry juice and commercially available juice sold as food supplements were analyzed using ICP-MS technique. The concentrations of 15 selected essential and toxic elements were determined in these juices.
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Methods for study of plant phosphoproteins
Válková, Martina ; Lochman,, Jan (referee) ; Fohlerová, Radka (advisor)
Reversibly phosphorylated proteins play a role in many fundamental cellular processes. An example is the cytokinin signal transduction pathway in plants that is mediated by the so-called two-component system involving histidine and aspartate phosphorylation. Due to the very low stability of phosphorylation of these amino acids, is difficult to find a suitable method for phosphorylation studies. The theoretical part of this bachelor thesis describes not only the current experimental approaches for analysis of protein phosphorylation in two-component systems but also is trying to propose new approaches for this analysis. There are described methods based on labeling of proteins using [?-32P] ATP and on the detection of released phosphate employing the colorimetric method or ICP-MS. Another possibility is sensitive identification of phoshorylated and non-phosphorylated forms of protein fused with GFP using CE-LIF technique. The practical part of the thesis deals with optimization of the selected colorimetric methods and also is focused on the preparation of the AHP5 protein fused with GFP for CE-LIF analysis.
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Determination of selected metals in unconventional fruit species
Křížová, Soňa ; Dočekalová, Hana (referee) ; Diviš, Pavel (advisor)
The aim of this diploma thesis is determination of selected metals in unconventional fruit species, specifically in cornelian cherry (Cornus mas), sea buckthorn (Hippophae rhamnoides) and medlar (Mespilus germanica).There is informationabout 16 analysed metals – As, B, Be, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Se, Sn, Pb, V, Zn. There are described analytical techniques for elemental analysis and methods for destruction biological material. Samples for analysis are prepared by using microwave mineralization and ICP-MS for detection. This is described in the experimental part of the diploma thesis. Analysis confirmed that unconventional fruits are rich sources of trace elements.
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Comparison of extraction methods for agriculture soil elemental analysis
Štursa, Václav ; Vespalcová, Milena (referee) ; Diviš, Pavel (advisor)
This bachelor thesis handles with optimization of preparation process of soil samples from vineyards for elemental analysis performed by ICP-MS. First part of the thesis deals with element analysis and its usage in agrotechnics and viticulture, description of toxic and nutrition properties of individual elements and legislation defining appropriate concentration limits of elements in agricultural land. Next part describes commonly used methods for elemental analysis such as AES, AAS, roentgen fluorescence spectrometry and ICP-MS. Finally, sampling methods and methods for sample preparation such as digestion and extraction are described. Experimental part follows up comparison of selected extraction methods (2M HNO3 extraction, temperature assisted 2M HNO3 extraction, aqua regia extraction and microwave-assisted digestion using mixture of HNO3 and H2O2). These methods were applied on certified reference materials. Extracts were analysed by ICP-MS technique Best results were achieved by 2M HNO3 extraction. This extraction method was subsequently applied on real soil samples from vineyard.
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