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Sequential injection analysis capability in automation of analytical processes
Novosvětská, Lucie ; Sklenářová, Hana (advisor) ; Polášek, Miroslav (referee) ; Hraníček, Jakub (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate (married name/maiden name): Mgr. Lucie Novosvětská / Mgr. Lucie Zelená Supervisor: assoc. prof. PharmDr. Hana Sklenářová, Ph.D. Consultant: PharmDr. Petr Chocholouš, Ph.D. Title of dissertation thesis: Sequential injection analysis capability in automation of analytical processes This dissertation, composed as a commented collection of four scientific articles and one undergoing project, introduces four novel applications in the field of automated flow methods and one application in the field of chromatographic methods used in analytical part of a complex pharmacological study. It the field of pharmaceutical analysis, three works were successfully optimized, validated, and published in scientific journals. Those works include: a) Automation of permeation studies within a sequential injection analysis system connected to a liberation unit and carrying out experiments with living cells. b) Pharmacological study of an antiretroviral drug efavirenz including its determination by fast chromatographic method in three types of sample matrices - in a medium from permeation studies with cellular models, in a Krebs solution from rat placenta perfusions, and in placenta tissue lysates. c) Determination of...
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.
Development of an ultra-high performance liquid chromatography for rifampicin determination
Alušicová, Sára ; Kozlík, Petr (advisor) ; Hraníček, Jakub (referee)
In this bachelor thesis, an ultra-high-performance liquid chromatography method (UHPLC) was developed to determine rifampicin in phosphate buffer (also called PBS). Rifampicin is a bactericidal antibiotic from the rifamycin family, which plays an important role in the treatment of tuberculosis. Optimized conditions for rifampicin determination in PBS were as follows: column kinetex UHPLC C18 100 (50x2.1 mm; 1.3 µm), mobile phase consisted of 10 mM aqueous ammonium formate buffer (pH 3.51) to which trifluoroacetic acid was added as an ion pairing agent (to a final concentration of 0.1%) (component A) and of ACN (component B). The measurement was carried out in the gradient elution mode of the mobile phase (time: 0-1-6-7-8-11, component B: 30,30,80,80,30,30). The flow rate was 0.300 ml / min at a column temperature of 30 ř C. The injection volume was 5µl. Under these optimized UHPLC conditions, a calibration dependence was measured in concenatraction range from 28,310-3 mg ml-1 to 4,4210-4 mg ml-1 . The limit of detection was 1,05∗10-4 mg ml -1 and the limit of quantification was 3,5∗10-4 mg ml -1 . Keywords: antibiotic, rifampicin, UHPLC
Novel fluorosensors based on naphthalimide derivatives
Garbárová, Veronika ; Dian, Juraj (advisor) ; Hraníček, Jakub (referee)
The aim of the diploma thesis was to prepare and characterize fluorescence sensor systems based on fluorophores and supramolecular components - cyclodextrins - attached to solid supports. In this work, functionalized 75 µm glass beads and two types of Nafion membranes were used as negatively charged solid surfaces. Derivatives of naphthalimide with a positively charged part allowing the attachment to surfaces were synthesized. The positively charged naphthalimide derivative was then attached on negatively charged surfaces via electrostatic interactions and the binding to the solid supports was examined using UV-VIS spectroscopy. Alternatively, the positively charged β-cyclodextrin derivative was also attached to the surface in an equimolar ratio with PNI-HEMPDA. The focus of the work were measurements of fluorescence sensor responses in the gas and liquid phase to linear alcohols - methanol to n-hexanol - for all sensor systems. For the studied sensor systems, the selected sensor parameters were determined - sensitivity, the limit of detection, linear dynamic range and a sensor response time constant. A practical application of the novel sensor system for the detection of ethanol in gasoline was examined. Fluorescence sensor response measurements of the prepared systems based on naphthalimide and...
Applied experiments with the use of measuring instruments for the analytical chemistry teaching at high schools
Břížďala, Jan ; Hraníček, Jakub (referee)
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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...
Determination of zinc in food supplements
Nedorostová, Helena ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
- 1 - Abstrakt Tato bakalářská práce je zaměřena na stanovení zinku (zinečnatých iontů) v potravinových doplňcích pomocí atomové absorpční spektrometrie. Součástí práce je také porovnání mezí detekce dvou odlišných atomových spektrometrů. Cílem práce bylo zjistit optimální podmínky a vliv interferencí na stanovení zinku, nalézt vhodnou metodu pro převedení vzorku do roztoku, a také porovnat meze detekce u použitých přístrojů. Optimalizovanými parametry byla výška paprsku nad hranou hořáku, průtoková rychlost acetylenu, otočení hořáku, šířka spektrálního intervalu, typ plamene. Převedení pevného vzorku do roztoku bylo provedeno ve vodě za laboratorní i zvýšené teploty, v kyselině dusičné nebo kyselině dusičné s přídavkem peroxidu vodíku, též za zvýšené teploty. Analyzovány byly tyto potravinové doplňky: Centrum od A až po železo, Walmark- vápník, hořčík, zinek, Spektrum 50+, Calibrum 50 plus, Supradyn Energy Complex. Množství zinku v potravinových doplňcích bylo stanoveno na spektrometru GBC 933 AA v kolmém uspořádání. K porovnání meze detekce byly použity přístroje GBC 933 AA s výbojkou s dutou katodou a ContrAA 700 s xenonovou výbojkou. U obou přístrojů byl pro experiment použit plamen obsahující acetylen-vzduch. Pro stanovení zinku byla pomocí standardních roztoků vytvořena kalibrační křivka, z níž byly...
Comparison of various approaches to determination of antimony by atomic fluorescence spectrometry
Adámková, Dominika ; Červený, Václav (advisor) ; Hraníček, Jakub (referee)
Bakalářská práce se zabývá porovnáním tří způsobů generování těkavých sloučenin pro stanovení antimonitých a antimoničných iontů pomocí atomové fluorescenční spektrometrie. Pro porovnání jednotlivých stanovení byly vždy nejprve nalezeny nejvhodnější experimentální podmínky. Protože je chemické generování považováno za nejúčinnější v porovnání s ostatními typy generování a je také nejčastěji používáno, bylo charakterizováno jako první. Bylo dosaženo limitu detekce 0,12 ppb pro Sb3+ a 0,28 ppb pro Sb5+ . Ovšem nejvyšší citlivosti a nejnižšího limitu detekce bylo dosaženo pro elektrochemické generování hydridu antimonu. Metoda EcHG byla přibližně 4×citlivější než technika CHG. Dosaženo bylo limitu detekce 9 ppt pro Sb3+ a 45 ppt pro Sb5+ . Nejnižší citlivost byla získána podle předpokladu při UV - fotochemickém generování, a to přibližně 9×nižší oproti elektrochemickému generování. Celkově stanovení antimonitých iontů bylo nejméně 4×citlivější než stanovení antimoničných iontů. Podle tvaru píku usuzuji, že tvorba těkavé sloučeniny probíhala u všech způsobů generování v případě Sb5+ pomaleji než u Sb3+ . Klíčová slova Atomová fluorescenční spektrometrie, antimon, generování těkavých sloučenin, chemické generování těkavých sloučenin, UV - fotochemické generování těkavých sloučenin, elektrochemické...
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...
Optimization of atomization conditions for bismut, lead and tellurium hydrides for development of hydride atomizers.
Štádlerová, Barbora ; Hraníček, Jakub (advisor) ; Spěváčková, Věra (referee)
This Master thesis is a part of a project: Hydride atomizers for atomic absorption and atomic fluorescence spectrometry - new horizons (GA ČR, P206/17-04329S, principal investigator: prof. RNDr. Jiří Dědina, CSc. DSc.) of which the general target is to make a leap towards the ideal hydride atomizer by optimization of atomization based on the knowledge of the distribution of free atoms and hydrogen radicals inside the atomizers. This thesis contributes to the project by optimizing the atomization parameters for atomic absorption spectrometry with hydride generation. The atomization parameters were optimized for three different types of atomizers - multiatomizer, diffusion flame and "flame-in-gas-shield" atomizer using three different analytes - bismuth, lead and tin. Optimal atomization parameters were found for each of the atomizer and each of the analyte - carrier gas flow and flow of other gases if needed for the analysis. Calibration curves and analytical figures of merit such as sensitivity, LOD and LOQ were estimated. Final comparison is based on the data obtained from calibration curves. MDF and FIGS atomizers are mostly used with AFS detection and they provide lower sensitivity and higher detection limits with AAS detection in comparison with MMQTA. Since the analytes are known to trap...

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