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Determination of calcium and magnesium in honey samples by atomic absorption spectrometry
Čudová, Andrea ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
This bachelor thesis is focus on the determination of calcium and magnesium in selected honey samples. Determination is performed by atomic absorption spectrometry with a flame atomization technique (F-AAS) by using an acetylene-air flame. The first part of the bachelor thesis is devoted to finding the optimal conditions of the method for further measurement of individual honey samples. These parameters are beam height above the burner edge and acetylene flow rate. Then, under these optimal conditions, the basic characteristics of calcium and magnesium determination (repeatability, sensitivity, limit of detection and limit of quatification) were found. In the second part of this bachelor thesis, the calcium and magnesium determination are performed in the honey samples. A total of 15 honey samples are analysed. The honey samples are prepared by local beekeepers from Czech Republic and retail chains (Tesco). The measured values are recorded in tables and statistically evaluated. The determined calcium concentrations range is 7.11 - 66.8 µg/g, for magnesium to 8.79 - 92.2 µg/g. Finally, the values obtained for honeys from the Czech Republic are compared with data reported in foreign studies. Key words: Atomic absorption spectrometry, flame atomization, magnesium, calcium, honey
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Analysis of selected elements in dendrological sample of spruce trunk
Pastrňáková, Aneta ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
The aim of this bachelor thesis was to determine selected elements, specifically iron, manganese, sodium, potassium, calcium, magnesium, barium, copper, zinc, strontium and aluminium in the sample of a spruce wood, taken from a dry tree from an area of South Bohemia. As a suitable and sufficiently sensitive method an atomic absorption spectrometry with flame atomization was used in this bachelor thesis. Before the analysis optimal conditions for the determination of these elements were experimentally found. The beam height above the burner edge and the acetylene flow rate were optimized depending on the type of oxidant used. Under the optimal conditions, the basic characteristics of the determination of individual elements were determined. These characteristics include mainly the limit of detection and quantification, sensitivity and repeatability. Optimized methods for determination of the selected elements were further applied for the analysis of real spruce wood samples. These samples were prepared by decomposition of the wood in a microwave device in the presence of nitric acid. In order to suppress interference, the suitable reagents were added to the analyzed samples to determine the selected elements (sodium, potassium, magnesium, calcium, barium). In total, 22 samples of wood of different...
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Determination of Titanium and Phosphorus by Atomic Absorption Spectrometry
Jeníková, Eva ; Hraníček, Jakub (advisor) ; Rychlovský, Petr (referee)
Předkládaná bakalářská práce se zabývá optimalizací metod stanovení titanu a fosforu technikou atomové absorpční spektrometrie s plamenovou atomizací ve složení acetylen-oxid dusný. Pro jednotlivá stanovení byly experimentálně nalezeny optimální hodnoty pro průtokovou rychlost acetylenu, koncentraci přídavku hliníku či vápníku, výšku paprsku nad hranou hořáku a jiné faktory pro zvýšení analytického signálu. Za těchto experimentálně zjištěných podmínek bylo provedeno stanovení a zjištění základní charakteristiky metod u obou prvků. Významnost stanovení těchto dvou prvků souvisí s tím, že materiály na bázi titanu a oxidu titaničitého povrchově modifikované sloučeninami fosforu jsou perspektivní pro řadu biomedicínských i průmyslových aplikací. Powered by TCPDF (www.tcpdf.org)
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Application of Atomic Absorption Spectrometry for Determination of Selected Elements from Potential Ecological Burden Area
Juránková, Lada ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
This work is focused on the determination of selected (chemical) elements (Fe, Mn, Zn, Cr, Na, K, Mg a Ca) in a potential ecological burden area using flame atomic absorption spectrometry as a detection technique. A potential ecological burden is represented by tires which are used as a construction material or as an environment surrounding for growing decorative and consumable plants. Analytes were determined in plant origin samples. Firstly, the samples were dried in a laboratory electric dryer. The weighted amount of a dried sample (approximately 0.2 g) was digested inside a microwave decomposition device with an addition of nitric acid and hydrogen peroxide. An optimization of experimental parameters was done for each of the elements before sample measuring. A burner height was optimized and 8 mm height was chosen as a optimum for most elements. Under the optimum condition basic characteristics were measured for each element separately. These characteristics included limits of detection that were: 0.05; 0.01; 0.08; 0.21; 0.02; 0.01; 0.01; 0.01 mg L-1 for the following elements: Fe, Mn, Zn, Cr, K, Ca, Mg and Na, respectively. The limits of quantification, sensitivity and repeatability were determined for each element as well. A significant attention was paid to the content of zinc in the studied...
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Comparison of selenium extraction efficiency from food supplements
Molnárová, Lucia ; Hraníček, Jakub (advisor) ; Červený, Václav (referee)
The aim of this bachelor thesis was comparison of selenium extraction efficiency from food supplements which contain various declared forms of selenium. The method of atomic absorption spectrometry with flame atomization was used to determine the efficiency of the extraction. The first step for the determination of selenium in four real samples was the experimental finding of optimal conditions for selenium determination by flame AAS technique. Optimized parameters included the flame composition, the fuel flow rate, the angle of burner rotation, the horizontal burner position and the spectral range. During the testing the flame composition, higher responses were measured by using air as an oxidant, and therefore acetylene-air flame was used to other optimize and measure real samples. After optimization of the conditions, the calibration dependence was determined and the basic characteristics of the measurements were calculated. The detection limit and determination repeatability, sensitivity and operating range were determined for selenium determination. The detection limit was 0.12 mg dm-3 . The real samples of the food supplement tablets were mechanically homogenized and transferred to aqueous solutions, which were subsequently analyzed by the optimal conditions. The highest extraction efficiency...
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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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Determination of lead and cadmium in fruits and vegetables extracts by atomic absorption spectrometry
Záškodová, Terezie ; Hraníček, Jakub (advisor) ; Červený, Václav (referee)
The content of this thesis was to analyse fruit and vegetable extracts. In the samples, the concentration of lead and cadmium was determine by atomic absorption spectrometry. First, it was necessary to conduct an optimalization study to find the optimal conditions of the method and select the appropriate method of atomization of the sample. It was chosen between flame and electrothermal atomization. For optimization, the following parameters were studied for atomization in flame: beam height above the burner, fuel flow rate, horizontal burner position, spectral interval width and lamp supply current. An optimization study for electrothermal atomization included the effect of atomization a pyrolysis temperature on signal size. Standard lead and cadmium solutions were used to determine the detection limits of the instruments used. The limit of detection in flame atomization was for lead respectively cadmium 0,002 mg/l, resp. 0,003 mg/l. In electrothermal atomization the detection limit was for lead, resp. cadmium 0,026 μg/l, resp. 0,029 μg/l. The experimentally determined values were statistically processed and the lead and cadmium contents were compared with the lead and cadmium limit values that may be contained in a sample of fruit and vegetables according to Commission Regulation (EC) No...
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Determination of rubidium in selected plant extracts by atomic absorption spectrometry
Šatrová, Lucie ; Hraníček, Jakub (advisor) ; Jelínek, Ivan (referee)
In this diploma thesis, rubidium in plant material samples was determined by atomic absoption spectrometry. Determination of plant material rubidium was performed on two different atomic absorption spectrometers (GBC 933 AA and ContrAA 700) for comparison. The selection of a proper method of atomization was essential, therefore optimizations for the flame atomizer and electrothermal atomizer were performed. On the GBC 933 AA, flame atomization was tested. The flow rate of the acetylene-air, vertical and horizontal flame profile, spectral interval width was optimized for the instrument. On the ContrAA 700, the conditions for flame atomization were optimized as well as for electrothermal atomization. The optimized parameters included the acetylene-air flow rate and the vertical flame profile again. For the electrothermal atomization, the temperature dependence of pyrolysis and the temperature dependence of atomization were optimized. Under experimentally determined optimal conditions, the determination of rubidium in fruit and vegetable juice samples was performed by the method of calibration curve. Rubidium usually accompanies toher alkali metals. In the absence of essential biogenic elements iportant for plant growth, rubidium is able to help out and take on the role of potassium.
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Analysis of selected elements in dendrological sample of spruce trunk
Pastrňáková, Aneta ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
The aim of this bachelor thesis was to determine selected elements, specifically iron, manganese, sodium, potassium, calcium, magnesium, barium, copper, zinc, strontium and aluminium in the sample of a spruce wood, taken from a dry tree from an area of South Bohemia. As a suitable and sufficiently sensitive method an atomic absorption spectrometry with flame atomization was used in this bachelor thesis. Before the analysis optimal conditions for the determination of these elements were experimentally found. The beam height above the burner edge and the acetylene flow rate were optimized depending on the type of oxidant used. Under the optimal conditions, the basic characteristics of the determination of individual elements were determined. These characteristics include mainly the limit of detection and quantification, sensitivity and repeatability. Optimized methods for determination of the selected elements were further applied for the analysis of real spruce wood samples. These samples were prepared by decomposition of the wood in a microwave device in the presence of nitric acid. In order to suppress interference, the suitable reagents were added to the analyzed samples to determine the selected elements (sodium, potassium, magnesium, calcium, barium). In total, 22 samples of wood of different...
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