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The utilization of quartz microbalance for detection of toxic compounds
Králová, Miroslava ; Jelínek, Ivan (advisor) ; Opekar, František (referee)
v angličtině: This work is aimed at the study of sensor response of quartz microbalance towards biologically active substances such as glycerin and toxic substances, namely ethylene glycol, methanol and acetonitrile in liquid phase. These toxic organic compounds are widely used in chemical industry as solvents or anti-freeze components. Glycerin is commonly utilized in cosmetic industry as a moisturizer. As human can easily get into contact with these compounds, they should be easily detectable. If tested senzor proves to be suitable for detecting these substances, it will be possible to follow preliminary results and develop the device for practical industrial usage.
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Synthesis and Characterization of Arylspiroborates
Sedláčková, Simona ; Jelínek, Ivan (advisor) ; Sobotníková, Jana (referee)
Arylspiroborates have some very interesting properties, which include biological activities and the potential anti-tumor activities. The aim of the thesis was to prepare some complexes using mainly phenolic ligands (catchol, pyrogallol, 3-methoxycatechol, 2,3-dihydroxynaphthalene and 4tertButylcatechol) and their detailed characterization using ESI-QqTOF. With some of these prepared complexes collision experiments were performed and based on the results, the fragmentation mechanisms for these substances were proposed.
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Use of the modern separation techniques for the analysis of insect pheromones
Žáček, Petr ; Jelínek, Ivan (advisor) ; Pacáková, Věra (referee) ; Cvačka, Josef (referee)
(EN) Communication mediated by chemical compounds (semiochemicals) is the most important way of information transfer in insects, especially in the social species. Gas chromatographic methods (one-dimensional, two-dimensional comprehensive, and preparative arrangement) coupled with mass spectrometric and/or electroantennographic detector were used for volatile or semivolatile semiochemicals analysis in various insect species. In this Thesis, biosynthesis of the bumblebee male sex pheromone in species Bombus terrestris, B. lucorum, and B. lapidarius was studied using putative biosynthetic precursors (sodium acetate, fatty acids) labeled with 2 H and 14 C. For the purpose of labeled volatile metabolites analysis, a method of separation and detection of isotopically labeled compounds in two-dimensional comprehensive gas chromatography was studied (2 H, 13 C). An "inverse isotope effects" was confirmed for compounds labeled with both isotopes in all examined types of columns. Concerning the biological samples, analysis of in vitro incubated tissues with labeled sodium acetate showed that pheromone components are synthesized de novo in the labial gland in B. terrestris and B. lucorum. Nevertheless, experiments of in vivo incubation of deuterated fatty acids confirmed biotransformation of the precursors...
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Determination of barbituric acid by SIA-technique with spectrophotometric detection
Horáková, Jana ; Hraníček, Jakub (advisor) ; Jelínek, Ivan (referee)
This thesis is focused on the determination of barbituric acid using two methods of flow analysis: flow injection analysis and sequential injection analysis, with spectrophotometric detection. Two reactions were selected for the determination of barbituric acid and different experimental conditions were optimized conditions for its determination. In the case of flow injection analysis, the concentration and flow rates of many reagents, the sample volume and the volume of the reaction coil were optimized. In the case of sequential injection analysis the same parameters except the optimum volume of the reaction coil were optimized. The optimal volume of the reaction coil was replaced by the optimum retention time in the mixing coil. Determination of barbituric acid by reaction with a nitroaniline mixture achieved a calibration range from 2,0.10-6 to 1,2.10-4 mol dm-3 and from 3,9.10-6 to 6,2.10-5 mol dm-3 using using FIA and SIA method, respectively, under the optimal conditions. Determination of barbituric acid by inhibition effect on the reaction between hydrochloric acid and bromate ions served a calibration range from 5.10-6 to 3.10-5 mol dm-3 using FIA method and 2.10-5 to 1.10-4 mol dm-3 using methods SIA under optimal conditions. Powered by TCPDF (www.tcpdf.org)
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Use of liquid chromatography in pharmaceutical analysis and preparation of monolithic stationary phases for thin-layer chromatography
Vojta, Jiří ; Coufal, Pavel (advisor) ; Tůma, Petr (referee) ; Jelínek, Ivan (referee)
(EN) In the first part of this work, analytical methods for determination of impurities of active pharmaceutical ingredients (API) in combined pharmaceutical dosage forms were developed and validated. Development of the methods covered both the optimization of sample preparation procedure and chromatographic conditions. The methods were validated according to International Conference on Harmonization guideline and both of them were confirmed to be able to analyze stability samples. Impurities in paracetamol, codeine phosphate hemihydrate and pitophenone hydrochloride in the presence of fourth API fenpiverinium bromide were separated by using ion-pair reversed phase chromatography with gradient elution. Symmetry C18, 250 x 4,6 mm, 5 µm heated to 35 řC was used as a separation column. A diode array detector was used. The detection wavelengths were set as follows: 220 nm for paracetamol impurity K, 245 nm for paracetamol and its other impurities and 285 nm for codeine, pitophenone and their impurities. Impurities in valsartan, amlodipine besylate and hydrochlorothiazide were separated by reversed phase UHPLC method with gradient elution. Chromatographic column Zorbax Eclipse C8 RRHD, 100 x 3,0 mm, 1,8 µm heated to 30 řC and spectrophotometric detection were used. The detection wavelengths were set as...
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Optimization of conditions for determination of trimethylsilylphosphates by GC-MS method
Blechová, Karolína ; Čabala, Radomír (advisor) ; Jelínek, Ivan (referee)
Fosfolipidy jsou důležitou součástí buněčných membrán, kde vytváří dvojvrstvy, které jsou charakteristické pro jednotlivé skupiny bakterií. Vlivem prostředí se mohou měnit růstové a produkční vlastnosti bakterie, které je možné sledovat změnou zastoupení fosfolipidů v membráně. K identifikaci a stanovení bakteriálních fosfolipidů se běžně využívá tenkovrstvá nebo kapalinová chromatografie. Pro stanovení polárních částí fosfolipidů byla použita plynová chromatografie. Metoda slouží jak k identifikaci, tak k určení celkového zastoupení polárních částí (fosfát, fosfoglycerol, fosfoethanolamin a fosfoserin) v molekule. Před vlastní analýzou je nutné polární části derivatizovat. Princip zvolené derivatizace spočívá v použití dvou různých silylačních činidel. K nalezení optimálních podmínek přípravy vzorků byl použit chemometrický postup označovaný jako experimentální design, který umožňuje určit faktory a jejich kombinace, které mají na zkoumanou odpověď největší vliv. Cílem bakalářské práce je vývoj a statistická optimalizace přípravy vzorku pro identifikaci standardů fosfátu a fosforylovaných sloučenin (fosfoglycerol, fosfoethanolamin a fosfoserin) z cytoplazmatické membrány bakterie Bacillus subtilis. Klíčová slova optimalizace, derivatizace, silylace, biologicky významné fosfáty, plynová chromatografie
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Development of high-performance liquid chromatography methods for determination of major components of tobacco
Rozkovcová, Lucie ; Jelínek, Ivan (advisor) ; Křížek, Tomáš (referee)
The aim of this work was development of high-performance liquid chromatography method with DAD detection for determination of nicotine in tobacco. Standard operating procedure used by World Health Organization was chosen as comparison of the developed method. Optimized high performance chromatography method is suitable for determining nicotine in tobacco. Limit of detection for this method was 0,0003 mg/ml and limit of quantification was 0,0010 mg/ml. Optimization of preparation of samples was significant part of this thesis. Sample preparation procedure was made substantially easier in comparison to other commonly used methods. Nicotine content was determined from real tobacco leaves samples, cigarette tobacco filler, nicotine cartridge for electronic cigarettes and pipe tobacco. Satisfactory relative standard deviation was achieved for all types of samples. Next part of this thesis focused on study of determining polyphenols using high-performance liquid chromatography with diode array detector. Chosen analytes were chlorogenic acid, caffeic acid, rutine, scopoletine and quercitrine. Among the five tested analytes, the highest sensitivity was achieved for chlorogenic acid and caffeic acid. All of the analytes achieved low limits of detection and quantification. Key words Liquid chromatography,...
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