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Determination of selected elements in cereal flours and their gluten-free alternatives
Venclová, Veronika ; Hraníček, Jakub (advisor) ; Nováková, Eliška (referee)
This study deals with the determination of calcium, magnesium, phosphorus, potassium, sodium, iron, zinc, copper, manganese and molybdenum in cereal gluten flours and its gluten-free alternatives. The flour samples were digested using a microwave device and the elements in solution were subsequently determined using an inductively coupled plasma mass spectrometer. Optimization of the digestion of the selected flours was performer prior to the actual determination of the elements. The aim of the work was to determine the above listed elements in the flour samples and to establish a basic overview of the elemental composition of the different flours. This overview and comparison of the different flours is intended to help the people with celiac disease to choose gluten-free alternatives to wheat flour. Keywords Inductively coupled plasma mass spectrometry, microwave digestion, calcium, magnesium, phosphorus, potassium, sodium, iron, zinc, copper, manganese, molybdenum, wheat flour, gluten-free flours, celiac disease
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Determination of calcium, magnesium and phosphorus in selected types of animal bones
Škardová, Alice ; Hraníček, Jakub (advisor) ; Kozlík, Petr (referee)
This research focuses on the elemental analysis of selected elements (calcium, magnesium, and phosphorus) within the bones of various animal species, aiming to make comparative nutritional assessments. The obtained bone samples were subjected to mechanical grinding and then quantitatively weighed into collapsible cartridges. Using high-pressure microwave decomposition with the incorporation of nitric and hydrochloric acid, the samples were transformed into solution form, which was then appropriately diluted. The analysis of the liquid samples was carried out using a mass spectrometer with inductively coupled plasma. The observed composition for each sample was calculated using the calibration curve, accounting for both sample mass and dilution factors. All results obtained exceeded the detection limit for calcium 0.38 mg/l, magnesium 0.037 mg/l, and phosphorus 0.078 mg/l. The main finding of this research is the complete understanding of the elemental makeup present within the bones of distinct animal species.
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Sewage sludge – a secondary source of environmental contamination with heavy metals
Sysel, Petr ; Zlámalová Gargošová, Helena (referee) ; Komendová, Renata (advisor)
This work deals with the elementary trace analysis of sewage sludge as a potential source of risk elements when applied to agricultural land. A total of 24 samples were analyzed, divided into two sets with different collection dates. The total content of zinc, copper, chromium, lead, mercury and cadmium in sewage sludge, as well as amount of risk elements that are extracted from sludge to water in 24 hours, was determined. Atomic absorption spectrometry was chosen for the analysis. It was found that the risk elements are in sewage sludge in amounts and order Zn (254.68 – 3084.53 mg/kg) > Cu (6.18 – 961.89 mg/kg) > Cr (26.95 – 387 .91 mg/kg) > Pb (0.84 – 155.30 mg/kg) > Hg (0.50 – 4.12 mg/kg) > Cd (0.06 – 2.61 mg/kg). A lower amounts of analyzed metals in the aqueous extracts than their total amounts in sludges were observed. The concentration of mercury and cadmium in the aqueous extracts was below the detection limits. It was evaluated that the risk elements in sewage sludge are found in less water soluble compounds. The results also show that the concentration of risk elements in the sludge does not depend on the number of equivalent inhabitants for which the treatment plant is dimensioned.
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The content of selected elements in fruiting bodies of mushrooms with ecological relationship to white birch
KREJSA, Jiří
The contents of 21 risk and essential elements were determined in fruiting bodies of four macrofungi species with ecological connection to white birch. Leccinum scabrum and Leccinum versipelle were common mycorrhizal edible mushrooms, while Piptoporus betulinus and Inonotus obliquus were parasitic mushrooms with medicinal effects. The samples were taken from two locations in Šumava mountains - near the town of Vimperk and near the small village of Křišťánovice. Simultaneously with fruiting bodies of mycorrhizal mushrooms, underlying substrates were taken for determination of bioconcentration factors.
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Elemental analysis of selected types of herbal teas
Adámková, Petra ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
In this bachelor thesis the concentrations of magnesium, potassium, manganese, zinc, copper, chromium, cadmium and lead in selected herbal teas and their infusions were determined. Teas from two competing producers on the Czech pharmaceutical market were selected for analysis. The aim of this work was a mutual comparison of selected tea samples in terms of their elemental content. An indicative study of the effect of water temperature and leaching time on the release of elements into the solution during the preparation of the pickle was carried out. The applied method included the decomposition of samples in a microwave device in the presence of concentrated nitric acid and analysis of the composition of the prepared solutions using ICP-MS. The results showed that the element contents differ according to the type of plant and according to the producer. Furthermore, it was proven that the leaching time has a greater influence on the release of elements into the solution than the water temperature. In this work, it was also verified that the ICP-MS method was suitable for determining the concentrations of all selected metals due to low detection limits. Key words Mass spectrometry, inductively coupled plasma, herbal teas, metals, microwave decomposition
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Determination of zinc, cadmium and nickel in leaves by inductively coupled plasma-mass spectrometry
Plodík, Michal ; Hraníček, Jakub (advisor) ; Červený, Václav (referee)
Práce je zaměřena na stanovení těžkých kovů (zinku, kadmia a niklu) v listech různých druhů stromů. Vzorky byly odebrány z různých lokalit na území České republiky. Pro analýzu byla použita hmotnostní spektrometrie s indukčně vázaným plazmatem, která je dostatečně citlivá pro předpokládané nízké koncentrace vybraných kovů. Pro stanovení koncentrace byla klíčová příprava vzorků pro mikrovlnný rozklad v koncentrované kyselině dusičné. Naměřené koncentrace sledovaných kovů se lišily nejen mezi lokalitami a jednotlivými rostlinnými druhy, ale také v rámci jedné lokality. Použitá metoda ICP-MS prokázala dostatečnou citlivost i u prvků s přirozeně nízkou koncentrací v životním prostředí, což bylo v této práci kadmium.
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Determination of selected metals in tea samples and bag materials
Hlávka, Jan ; Nováková, Eliška (advisor) ; Hraníček, Jakub (referee)
This bachelor thesis is dealing with determination of antimony in materials modern pyramid-shape tea bags. Possible presence of antimony in these materials, e.g. polyethylene terephthalate (PET) or mixed materials, is caused by using it like catalyst in production of polyethylene terphthalete. The goal of this bachelor thesis is the verification of hypothesis, that antimony is present in materials of pyramide tea bags and that it is released to consumed drink, if higher concentration of antimony is present, and that it could pose a health risk to the consumer. At the same time, I studied if tea leaves are contaminated by other toxic elements, from which some can result from intesive agricultural production. They can be used as pesticides or be presnet in industrial fertilizers. In this thesis I examined the content of As, Cd, Cu, Sb and Zn in tea leaves sold in pyramide bags. These pyramide bags were purchased in local supermarkets and shops. The content of Sb in bags was determined too. The applied method included the decomposition of samples in a microwave decomposition device and analysis of the composition of the resulting solution by the ICP-MS method. Determined contents of the investigated elements were expressed like content of element in the sample in dry mass and the results were compared...
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Determination of selected elements in potato tubers by atomic absorption spectrometry
Fořtová, Lucie ; Hraníček, Jakub (advisor) ; Kozlík, Petr (referee)
The main aim of this bachelor thesis was a determination of the elements K, Mg, Ca, Na, Zn and Fe in the potato tubers and in their boiled solution using the method of flame atomic absorption spectrometry. The chosen samples were late consumer potato tubers of Granada cultivar (boiling type B). It was necessary to optimize working conditions before the sample analysis. The optimal flow rate of acetylene ranged from 2.0 to 2.5 l/min using the flame acetylene-air. The flame acetylene-nitrous oxide was used only for calcium with flow rate 6.0 l/min. The optimal height of a beam above the burner edge was measured in interval 5 to 7 pieces of defined scale mentioned in a manual for spectrometer GBC 933 AA. Using the optimal conditions, the basic characteristics for individual methods of determination were characterized (LOD, LOQ, LDR, sensitivity, repeatability). Limits of quantification were following: 78, 31, 7.0, 8.0, 190 and 71 μg/l for K, Na, Mg, Ca, Fe and Zn, respectively. The optimal conditions were used for the determination of the selected elements in samples. The solutions were prepared from diversely processed potato tubers (whole, whole without skin, chopped without skin, skin) by boiling into deionized water. After the samples had cooled down, the concentrated nitric acid was added...
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