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1

Navrátilová, Romana. "Strukturní studium karboranů s využitím hmotnostní spektrometrie." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2009. http://www.nusl.cz/ntk/nusl-216532.

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Boron cluster compounds are substances clearly synthetic, which don't exist outdoors. This group covers boranes, heteroboranes and their derivatives. They are synthesized and examined mostly for their extraordinary structural and bonding properties. Their study also brought many remarkable findings and even allowed practical use of these compounds in science and technology. This thesis is focused on the application of mass spectrometry for the identification of boranes and heteroboranes and on the study of their fragmentation mechanisms using tandem mass spectrometry on spherical ion trap.
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Beneš, Ondřej. "Zpracování a visualizace hmotnostních spekter." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2014. http://www.nusl.cz/ntk/nusl-235426.

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One of new techniques in the field of analytical chemistry, which has more and more practical use, is mass spectrometry imaging. With its ability to record representation of substances in samples during the tissue analyze arise problem with a lot of output data which needs to be handled programmatically. The goal of this work is to create an software for processing and visualization data of new standard imzML. As a part of the work, the field of mass spectrometry, primarily MALDI TOF mass spectrometry, is briefly introduced. There are also introduced some methods for mass spectrometry data preprocessing. The work also contains a summary of current state of available software for processing and visualization of mass spectrometry data. With requests from cooperating laboratory a novel software is designed and implemented, which besides the visualization itself, can preprocess the data for example data smoothing with Savitzky-Golay method, internal calibration or peak detection with continuous wavelet transformation. The software was successfully tested on real data sets.
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3

Valla, Martin. "Systém pro zpracovaní skóre z metod identifikace proteinů v tandemové hmotnostní spektrometrii." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217552.

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The goal of my diploma thesis was finding a suitable method for unifying score values from various protein identification search tools in MS/MS mass spectrometry into one single score value. Data coming from the output of mass spectrometer are processed in two independent search tools Mascot and X!Tandem. These were selected especially for their wide usage in proteomic labs. Both results are evaluated through newly designed function and unified by single valued score clearly identifying found proteins. Newly designed scoring value is called Matascore and function producing this score was implemented in MATLAB. Function and its results were successfully tested by real data available in public databases on the Internet.
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4

Čumová, Martina. "Využití hmotnostní spektrometrie ke stanovení markerů oxidativního stresu a mykotoxinů." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2015. http://www.nusl.cz/ntk/nusl-233402.

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The first topic presented in the dissertation thesis is determination of isoprostanes as markers of oxidative stress and other compounds affected by presence of oxidative stress. Isoprostanes iPF2-III, iPF2-VI, iPF2-VI, astaxanthin and polyunsaturated fatty acids (PUFA), especially arachidonic acid (AA) were monitored in Atlantic salmon eggs (Salmo salar). Methods for the determination of these compounds have been developed and optimized using chromatographic separation coupled to conventional or mass spectrometric detection. Freshly laid eggs, eyed embryos and non-viable eggs were used to test a general hypothesis that egg viability can be affected by susceptibility to oxidative stress, either through the specific fatty acid concentration and/or the antioxidant capacity of the eggs. Levels of isoprostanes and arachidonic acid (AA) were significantly higher in non-viable eggs than in control (eyed embryos) as well as relative abundance of PUFA. While no difference of isoprostanes was found between freshly laid and control those from the Atlantic stock except iPF2-VI which was observed under the LOQ in the control. Higher levels of PUFA and AA in comparison with the control were observed in the freshly laid eggs. However, the only statistically significant difference was observed in the amount of astaxanthin. Different levels of PUFA and astaxanthin may be related to their biochemical consumption during the development of eggs. This work evaluated potential effect on the viability of eggs Salmo salar due to the presence of oxidative stress. The monitoring of mycotoxins in food and feed was the subject of the second topic. Mycotoxins are secondary metabolites produced by fungi. They are ubiquitous undesirable natural contaminants that are toxic for humans and animals. Today are known more than 500 mycotoxins. However, only few of them are regulated by the European Union. The European Food Safety Authority (EFSA) was asked by the European Commission to provide a scientific opinion on other mycotoxins for which statutory limits could be developed. In this study is proposed simultaneous screening allowing fast, reliable and sensitive approach, identification and quantification of 17 mycotoxins in food and feed sample. The method includes both mycotoxins regulated by the EU and selected mycotoxins required by the EFSA (aflatoxins, deoxynivalenol, nivalenol, zearalenone, fumonisin, ochratoxin A, T-2 toxin, HT-2 toxin, enniatins and beauvericin). Analytes are isolated by the modified QuEChERS method. For separation and target mycotoxins detection, ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC –MS/MS) was employed. The method also allows determination of ergot alkaloids (ergocornine, ergosine, ergocryptine, ergocristine and their respective epimers). The developed method was used either for monitoring mycotoxins and ergot alkaloids in feed and raw materials and barley and malt prepared from it.
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Čumová, Martina. "Využití separačních metod s hmotnostní detekcí pro studium degradačních produktů nových polymerních materiálů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2009. http://www.nusl.cz/ntk/nusl-216540.

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Synthetic polymer materials have been a part of human life since the 20th century. A variety of their use had resulted in a growing demand for their mass production, which then led to their increasing accumulation at waste dumps. After their deposition, these materials are exposed to many environmental factors causing their decomposition and subsequent release of the degradation products into the environment. This thesis is focused on the analysis of the photodegradation products from synthetic polymer materials and particularly polyurethane foams modified with the biodegradable fillers. One dimensional GC/MS and two dimensional comprehensive gas chromatography with time-of-flight mass spectrometry (GCxGC/TOF-MS ) were used for the measurements. The most of photodegradation products of polyurethane foams are injurious to health and environment.
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6

Žvaková, Veronika. "Detailní charakterizace pyrolýzního oleje pomocí separačních technik a hmotnostní spektrometrie." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-316220.

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The aim of this work is detailed characterization of pyrolysis oil by advanced analytical separation methods and mass spectrometry. During the pyrolysis process decomposition of complex organic material take place in the presence of high temperatures and the absence of oxygen. Condensable part of vapours and aerosols forms viscous liquid called pyrolysis oil which is a complex mixture of large amount of compounds. In this work samples from microwave pyrolysis of woodchips and sewage sludge from wastewater treatment plant Brno-Modřice were analysed. Samples were provided by Bionic Laboratories company. Samples were separated by column chromatography on activated silica. For detailed characterization of each fraction gas chromatography with mass spectrometry detection and comprehensive two-dimensional gas chromatography with mass spectrometric detection with time of flight analyser were used. Substances that have been identified can be divided into several groups: alkanes, alkenes, aromatic hydrocarbons, polycyclic aromatic hydrocarbons, alcohols, aldehydes, esters, carboxylic acid and heterocycles.
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7

Jurasová, Lenka. "Stanovení vybraných hormonálních přípravků pomocí kapalinové chromatografie s hmotnostním detektorem." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2012. http://www.nusl.cz/ntk/nusl-216864.

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This master’s thesis is focused on optimizing of the analytical method for the determination of selected drugs - estrone, estradiole, ethynylestradiol, estriole, diethylstilestrole, norethindrone, mestranole and progestrone in wastewater using liquid chromatography with mass spectrometry (LC/MS). Solid phase extraction (SPE) using Oasis HLB cartridges was chosen extraction method Different mobile phase, temperature, flow rates and mobil phase gradient were during the process of optimization. Samples of the wastewater were collectedat the inflow and outlow of the wastewater treatment plant in Břeclav and in University of Veterinary and Pharmaceutical Sciences Brno. Drugs were isolated from wastewater and preconcentrated using solid phase extraction (SPE) and determined by high performance liquid chromatography with mass spectrometric detection (HPLC/MS).
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8

Kuba, Pavel. "Zpracování a vizualizace dat z hmotnostního spektrometru typu TOF-MALDI." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230019.

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This thesis describes the development of control applications for the deposition machine and mass spectrometer. Thesis describes operation principles of both devices and their hardware specifications. Thesis also describes the design of developed applications. Functionality was tested on series of real measurements.
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Obalil, Jiří. "Miniaturizované techniky pro analýzu průmyslových kvasinek." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216334.

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Carotenoids are natural pigments that have antioxidation and antimutagenic abilities. They are produced with the help of new technological methods. For example, carotenoid yeast Rhodotorula glutinis produces -carotene with the yield of up to 6 – 10 mg/g of the dry substance. The method of the mass spectrometry with the nanoelectrospray in the positive mode was optimized for the determination of -carotene, lycopene and astaxanthin in this project. Ionizing voltage of 4 kV and the sample flow rate of 15 – 80 nl/min through the spray silica fused capillary with the internal diameter of 25 µm were found to be the optimum parameters of the analysis. A mixture of chloroform with the addition of ammonia was used as a spray solvent for both standard and cellular samples. During the process of ionization by nanoelectrospray, -carotene and lycopene form cation radical [M] • + with the molecular mass to charge ratio (m/z) of 536, while asthaxanthin forms the protonated molecule [M + H]+ with the m/z of 597. The partial lysis of individual Rhodotorula glutinis cells was demonstrated under microscope in the organic solvents tetrahydrofuran and dimethylsulfoxide. Chloroform, acetone, acetonitrille, methanol and isopropanol did not affect the cells after a 15 min treatment.
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10

Trčková, Marie. "Využití metody LC/MS k analýze vybraných přírodních fyziologicky aktivních látek." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216232.

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Presented work is focused on application of combined instrumental method RP-HPLC/ESI-MS in analysis of several groups of natural compounds with positive physiological activities. Especially some antioxidants were studied in commonly and abundantly consumed food. Moreover some other substances than standard compounds were observed in complex dies. In conclusion the HPLC/ESI-MS method is comparatively advantageous in phenolic analysis, while another type of ionisation would be used in case of carotenoid compound.
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11

Burešová, Jitka. "Využití separačních metod pro studium vybraných léčiv a pesticidů ve vodách." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2015. http://www.nusl.cz/ntk/nusl-234424.

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This work is focused on the study of penetration of pesticides and pharmaceuticals in the aquatic environment. The aim was to develop and verify the optimal method for long-term monitoring of the occurrence of selected pesticides and pharmaceuticals in surface waters. Two frequently used analgesics ibuprofen and diclofenac, and carbamazepine that is used to treat epilepsy, were chosen from the group of drugs. A group of 41 pesticides were selected for monitoring too. The attention was focused on a group of urea pesticides and phenoxyacetic acids, as well as on selected pesticides falling to the group of priority substances or identified as environmental quality standards. Some of pesticides were selected because their consumption in the Czech Republic exceeds 30 tons a year. Liquid chromatography with tandem mass spectrometry (LC / MS / MS) was used for the determination of selected analytes in surface waters. Two optimized analytical method were developed. Ten analytes were determined in negative ion mode and 34 analytes in positive ion mode. Solid phase extraction (SPE) was used for purification and concentration of the samples. Developed methodology was validated and used for monitoring of selected compounds in samples of surface waters from the Morava River basin. Samples were collected on the rivers Morava and Svratka monthly for two years. Samples from the river Blata and stream Nivnička were collected for one year. Surface water samples were also collected from the river Litava. Four samples were taken throughout the length of the flow during one day. Smaller streams were chosen for monitoring because of the probability of occurrence of pesticides. They flow abundantly agriculturally cultivated areas. Drugs ibuprofen and diclofenac were detected in all taken samples, carbamazepine mostly. Among the most commonly occurring pesticides were bentazon, diuron, isoproturon, carbendazim, MCPA, MCPP, propiconazole, tebuconazole and 2,4-D.
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12

Kerberová, Veronika. "Umělá sladidla a jejich případný vliv na ekosystém." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-295680.

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This diploma thesis deals with the determination and ecotoxicological assessment of artificial sweeteners. The diploma was focused on monitoring the most commonly used sweeteners, which includes acesulfam-K, cyclamate, saccharin and sucralose. These sweeteners were analyzed by liquid chromatography with mass spectrometry, using solid phase extraction for their concentration. The samples for their determination were taken from wastewater treatment plant in Modrice. Artificial sweeteners are synthetically produced substances, which is the main reason for their occurrence in waste water. Some of them are not efficiently removed from the wastewater treatment plant and penetrate into the environment. Analysis of the samples was found, that sucralose penetrates into the environment. The ecotoxicological effect of the sweeteners was evaluated via aquatic organisms, namely on the freshwater crustaceans Thamnocephalus platyurus and Daphnia magna, on the water plant Lemna minor, and the battery of tests was supplemented by a representative of the destructors Vibrio fischeri. For all sweeteners, LC20, EC20 and IC20 values were determined. For some sweeteners, LC50, EC50 and IC50 values were also determined. During testing, saccharin represented the highest toxicity.
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13

Guryčová, Hana. "Syntetické vonné látky ve vodním ekosystému." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2009. http://www.nusl.cz/ntk/nusl-216539.

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Synthetic fragrances or MUSK compounds are artificialy synthetised organic substances, used as fragrant constituents in various homecare products, such as cosmetics, detergents, air fresheners etc. The aim of diploma thesis was the quantification of some selected MUSK compounds in the influent and efluent of the water treatment plants.The method of quantification of MUSK compounds in organic matrix was also optimised during the research. Two modifications of solid phase microextraction were tested and evaluated. The analytes were identified and quantified by gas chromatography - mass spectrometry (GC/MS). The results were used to evaluate the amount of MUSK compounds in sewage waters and the ability of various water treatment plants to eliminate this kind of pollution from the water during the treatment process.
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Nohelová, Gabriela. "Bisfenol A ve vodním ekosystému." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2014. http://www.nusl.cz/ntk/nusl-217085.

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This diploma thesis deals with Bisphenol A, especially with its impact on the aquatic ecosystem. Information about its properties, production and current use are summarized here. Its harmful impact on the environment, especially on the aquatic ecosystem and the human body is characterized. Also the methods of its degradation within the aquatic environment have been described. A summary of the options of a determination of Bisphenol A in water samples is incorporated and the method of gas chromatography with mass spectrometry (GC/TOF MS) and comprehensive two-dimensional gas chromatography with mass spectrometry (GCxGC/TOF-MS) is compared in the experimental part. Analytical determination precedes the isolation of the analyte from the water samples by solid phase extraction (SPE) using SupelcleanTM ENVITM - 18 and derivatization using the silylation reagent, N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). The result of this work is the analysis of a series of real samples from wastewater treatment plants Brno Modřice and Luhačovice by a two-dimensional gas chromatography with mass spectrometry (GCxGC/TOF-MS).
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Hajdučková, Iva. "Stanovení výskytu toxických prvků ve vínech." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2013. http://www.nusl.cz/ntk/nusl-216907.

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The aim of this study was to determine the occurrence of selected toxic elements in wine. The theoretical part described technology of wine production and selected toxic elements (cadmium, lead, copper, zinc, nickel and chromium) in the terms of their impact on wine quality and their effects on the human organism. It provides an overview of instrumental analytical methods, which can be used for the analysis of toxic metals. In the experimental part inductively coupled mass spektrometry technique was used for the analysis of wine samples. The measured values are statistically processed and compared with current legislation.
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Brestovská, Marta. "Stanovení tenzidů ve vodách pomocí separačních metod." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2015. http://www.nusl.cz/ntk/nusl-217166.

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Surfactants are synthetically made surface-active agents contained in washing and cleaning products. They decrease the surface tension and remove dirt. Surfactants can be divided into three basic classes: anionic, cationic and non-ionic. Thanks to the massive use they penetrate into waste water and can disturb the environment. This diploma thesis deals with the occurrence of surfactants in water and their determination by separation methods, especially LC / MS.
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Nevědělová, Klára. "Stanovení vybraných fytofarmak a jejich metabolitů v odpadních vodách." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216446.

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This diploma thesis will be focused on the identification and quantification of selected phytopharmaceuticals ant theri transformation products using separation and spectrometric methods available in the laboratories of ICTEP.
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Borůvková, Tereza. "Stanovení polárních pesticidů v odpadních a povrchových vodách." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-240792.

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This work is focused on the determination of polar pesticides in surface and waste waters. In this study Mecoprop-P, MCPA, Dichlorprop-P, 2,4-D and MCPBA in differently loaded surface waters and communal waters from sewage treatment plants were analyzed. These herbicides are included in the group identified as environmental quality standards. Some of herbicides (2,4-D and MCPA) were selected because their consumption in the Czech Republic exceeds 30 tons a year. Samples were collected prom three rivers near town of Jaroměř (Elbe, Úpa and Metuje Rivers), from one river near the town of Brno (Svratka River) and from inflow and outflow of two sewage treatment plants (WWTP Jaroměř, WWTP Brno – Modřice). Particular rivers were chosen for monitoring due to the probability of occurrence of herbicides, because they flow through agriculturally cultivated areas. Solid phase extraction (SPE) was used for the isolation of target compounds and their concentration. Gas chromatography with tandem mass spectrometry (GC/MS/MS) was used for the determination of target analytes in surface and waste waters. Selected herbicides were detected in all collected samples.
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Cáhová, Miroslava. "Stanovení těžkých polycyklických aromatických uhlovodíků v půdách a sedimentech." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216379.

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This diploma thesis will be focused on the identification and quantification of PAHs with molecular mass exceeding 278 Da by separation and spectrometric methods available at the laboratories of ICTEP.
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Fojtíková, Nikola. "Diagnostika plazmatu generovaného v atmosféře simulující podmínky na Marsu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-445140.

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The aim of the diploma thesis was the diagnostics of plasma generated in the atmosphere simulating conditions on Mars. This diploma thesis is focused on the simulation of Mars’ atmosphere at atmospheric pressure and normal laboratory temperature. Due to the similar conditions of Mars' atmosphere with Earth, this planet has been explored in the past as well as up to now. Mars' atmosphere is composed mostly of carbon dioxide, which makes up more than 90 % of Mars' atmosphere. A glow discharge generated in a special reactor at atmospheric pressure at a flow of pure CO2 was used to simulate the atmosphere of Mars. Part of the measurement was performed only in pure CO2 with changing current of 20, 25, 30, 35 and 40 mA. Part of the measurements was focused on the study of the effect of the addition of various gases, such as nitrogen, hydrogen and methane, at changes in their flow rates of 1, 2, 3, 4 and 5 sccm. The products formed in the special reactor were analysed using a mass spectrometer with proton ionization and with a flight time analyser. Optical emission spectrometry was used for plasma diagnostics and composition. Mainly simple aliphatic hydrocarbons, alcohols, aldehydes, and ketones were detected. With increasing flow rates of the individual gases, more complex aromatic compounds with higher molecular weights were formed. Corresponding mass and optical emission spectra were measured simultaneously.
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Matejčíková, Eva. "Stanovení stability přípravku TauroLock." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-376887.

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This diploma thesis deals with the study of the anticoagulant and antimicrobial agent TauroLockTM, which is manufactured by the german company TauroPharm GmbH. Based on the background research and taking into account the equipment of analytical laboratories of the Institute of Chemistry and Technology of Environmental Protection, optimal methods of analysis were proposed and a series of experiments were carried out which focused on the determination of the active substance and degradation products of taurolidine in TauroLockTM which was stored for a certain period of time in real conditions. The main task of this work was to determine the presence of taurolidine as the active substance and formaldehyde as the undesirable product of its decomposition.
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Doležalová, Jana. "Stanovení alkylderivátů rtuti ve vodním ekosystému." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2009. http://www.nusl.cz/ntk/nusl-216536.

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Diploma thesis is oriented on the question of the fate and occurence of mercury and its derivatives in water ecosystems. At first, deep literature review will be worked out. At second, the optimal analytical procedure for the determination of mercury alkylderivatives in water ecosystem compartments will be proposed and verified. At third, real samples from selected water ecosystems will be taken and analyzed.
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Veverková, Radka. "Plazmochemická depozice tenkých fluorocarbonových vrstev." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-216697.

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Deposition of thin films is one of the most widespread applications used for the changes of surface properties of various materials. This diploma thesis is focused on diagnosing of thin film generated by a PECVD technique. The capacitively coupled RF discharge at low pressure was used for the thin films deposition using tetrafluoromethane (CF4) with addition of hydrogen (H2) as a precursor. The aim of the work was the search of optimal conditions for a hydrophobic thin layer preparation on the surface of polymer NOA. The depositions were performed in continuous and pulsed mode with different duty cycle. The discharge was monitored using optical emission spectroscopy and in situ mass spectrometry. Thin films structure and properties were characterized using water contact angle measurements, X-ray photoelectron spectroscopy, infrared spectroscopy and optical ellipsometry. The influence of varying power, gas mixture composition and discharge mode were investigated. Water contact angle was the highest for a deposition in a continuous mode. Decomposition processes inside the reactor were observed by using mass spectrometry and optical emission spektrokopie. X-ray photoelectron spectroscopy provided information about the chemical bonds represented on the surface of sample. These were mainly C – C/C – H, C – O, O = C - O groups for sample without layer. Other chemical bonds were observed after the deposition. These were mainly C – CF, CF2 and CF3 groups. The film thickness of about 8,2 nanometers was measured by optical ellipsometry. The obtained results may be used as a fundament for further more advanced study of plasma chemically prepared thin fluorocarbon films and their properties.
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Jagošová, Klára. "Hormony v čistírenských kalech." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-376816.

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Currently there is a spate of interest in the presence of pharmacologically active substances in the environment. These substances are excreted in active or metabolized form and with wastewater pass the wastewater treatment plant. Current treatment technologies do not always eliminate all pharmaceuticals effectively and therefore they enter the environment. One of these active groups is the group of steroid hormones. Steroid hormones belong to the group of endocrine disruptors and they are considered to be dangerous for the ecosystems. Due to the hydrophobic character of steroid hormones they undergo partial or total sorption from wastewater to sludge. Sewage sludge is the by product of wastewater treatment and contains heavy metals, organic contaminants and pathogenic bacteria. A part of produced sewage sludge is used as a fertilizer in the Czech Republic. This issue follows the regulation 347/2016 – conditions of agricultural use of sewage sludge. Waste policy of EU will alter the conditions of sludge disposal, so it is necessary to obtain data about the concentration levels, fate and behaviour of those pollutants. This thesis was focused on five natural female hormones and four synthetic, which are used as a part of contraceptive pills and substitutional hormonal therapy. Determination of hormones was performed in four steps including ultrasonic assisted extraction, clean up by solid phase extraction, derivatization and final analysis by gas chromatography with mass spectrometry on triple quadrupole in MS/MS mode.
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Šilhánková, Lenka. "Vývoj metody pro semikvantitativní stanovení mikroplastů v půdách metodou TGA-MS." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-376860.

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Plasty, pronikající do životního prostředí ať už neúmyslně či záměrně, mohou být fragmentovány za vzniku částic v řádu mikrometrů (tzv. mikroplastů) a znečišťovat tak půdní systémy. Doposud vyvinuté analýzy pro stanovení mikroplastů v půdách jsou především zaměřeny na kvalitativní stanovení, nicméně i jejich provedení se zatím stále potýká s různými úskalími. Navíc, téměř všechny tyto analýzy vyžadují časově náročnou předúpravu vzorku. V této studii jsme se zaměřili na vývoj nové analytické metody pro kvantitativní stanovení mikroplastů polyvinylchloridu (PVC) a polystyrenu (PS) v půdách bez předchozí úpravy vzorku pomocí termogravimetrické analýzy spojené s hmotnostní spektrometrií (TGA-MS). Pro analýzu byly použity vzorky modelové půdy s nízkým obsahem organického uhlíku, které byly spikovány na výslednou koncentraci 0,23–7 hm% PVC či PS. Vzorky byly pyrolyzovány s teplotním krokem 5 K min–1 až na teplotu 1000 °C. Pyrolýzní plynné produkty byly následně analyzovány s využitím hmotnostního spektrometru. Získaná data byla normalizována pomocí externího standardu (šťavelan vápenatý). Limity detekce se pohybovaly v rozmezí 0,08–5,3 hm% pro PVC a 0,005–0,7 hm% pro PS v závislosti na zvoleném m/z. Limity kvantifikace pak byly 0,3–17,7 hm% pro PVC a 0,002–2,2 hm% pro PS. Výsledky dokazují, že spojení TGA-MS může být konkurující semikvantitativní metodou pro stanovení mikro-PVC a mikro-PS v půdě s nízkým obsahem organického uhlíku.
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26

Maier, Jan. "Kvantitativní analýza inhibitorů tyrozinkinázy metodou kapalinové chromatografie s hmotnostní detekcí." Master's thesis, 2021. http://www.nusl.cz/ntk/nusl-446439.

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The submitted thesis is devoted to the quantitative analysis of tyrosine kinase inhibitors, specifically imatinib and nilotinib, by liquid chromatography-mass spectrometry method. The main purpose of developing this new method of analysis at the Department of Clinical Biochemistry and Diagnostics at the University Hospital in Hradec Králové was measuring and monitoring serum or plasma concentration levels of these drugs in patients with chronic myeloid leukemia, less often in patients with gastrointestinal stromal tumour. The main task during the elaboration of the thesis was to fully optimize and validate the method. Previously, this method for the analysis of tyrosine kinase inhibitors was routinely performed here by high-performance liquid chromatography with spectrophotometric (UV) detection. As part of the modernization of laboratory technology, they started to use high-performance liquid chromatography with mass spectrometry at the workplace. The analytes with their internal standards were obtained by a liquid-liquid extraction process. Then, samples were separated on a C18 reverse phase column using isocratic elution. Subsequently, both analytes were detected by a triple quadrupole tandem mass spectrometer with ESI ion source in a positive mode. As a part of the method validation was to...
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27

Rejšek, Jan. "Vývoj a aplikace technik ambientní hmotnostní spektrometrie." Doctoral thesis, 2017. http://www.nusl.cz/ntk/nusl-370610.

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(EN) Ambient mass spectrometry defines the versatile group of methods providing analysis of solid sample surfaces and liquids in an open atmospheric pressure environment, where the sample is simultaneously accessible to another treatment. Ambient mass spectrometry is a sharply developing research area in the analytical chemistry. It provides fast, direct analysis of objects without any sample pretreatment with the use of the mass spectrometer. Desorption electrospray ionization (DESI) and desorption atmospheric pressure photoionization (DAPPI) equipped with software control of the sample holder were investigated in this doctoral thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate and they are suitable tools for mass spectrometry imaging (MSI) of low molecular organic compounds, where the chemical identity of molecules present on a surface is examined as a function of spatial distribution. This project deals with applications and instrumental development. As for the applications, the position of the defense glands on insect bodies, separation of the lipids in complex mixtures on thin-layer chromatography (TLC) plates, or steroid metabolites in woman urine during pregnancy were thus investigated. As for the instrumental development, the most...
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28

Rejšek, Jan. "Využití ambientních ionizačních technik v hmotnostní spektrometrii." Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-324164.

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Keywords: ambient ionization techniques; mass spectrometry; desorption electrospray ionization; desorption atmospheric pressure photoionization; thin layer chromatography; lipids, mass spectrometry imaging Ambient ionization technique in mass spectrometry is an ionization, which carries out in open space outside the machine and which does not require any, or only a minimal sample pretreatment. DESI (desorption electrospray ionization) and DAPPI (desorption atmospheric pressure photoionization) equipped with software control of the spray emitter position for analysis of low molecular organic compounds were investigated in this thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate. Conditions for the successful analysis of phospholipids, wax esters and some other compounds were developed. Ambient ionization techniques were quantitatively compared. The application was HPTLC/DESI-MS of lipid's mixture and HPTLC/DAPPI-MS of vernix caseosa. DAPPI-MS was applied for the analysis of termites of Prorhinotermes genus (Isoptera, Rhinotermitidae). Pilot experiments of two dimensional analysis and mass spectrometry imaging were realized.
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29

Kosíková, Lenka. "Chirální rozeznávání pomocí hmotnostní spektrometrie." Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-304410.

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Title: Chiral recognition by mass spectrometry Author: Bc. Lenka Kosíková Department: Department of Organic Chemistry Supervisor: doc. Mgr. Jana Roithová, Ph.D. This work is focused on the use of mass spectrometry as the analytical method for chiral recognition in the gas phase. We have examined formation of complexes (S and R) isomers [dimethyl-2,2'-dihydroxy-1,1'binaphthalene-3,3'-dicarboxylate] with sodium. Chiral effect for the fomation of sodium dimers is 1,34±0,06 and that for formation of trimers 2,38±0,22 in favor of the formation of homochiral complexes. Part of the work is devoted to the preparation of isotopically labeled ester [(R)-(−)- di(D3-methyl)-2,2'-dihydroxy-1,1'binaphthalene-3,3'-dicarboxylate]. Mixing of equimolar amounts of D3-(R) and unlabeled (S) isomers leads to the artificial racemate, while we can still distinguish the enantiomers using mass spectrometry. Another part represents the study of the complex formation between (S and R) isomers of [dimethyl-2,2'-dihydroxy-1,1'binaphthalene-3,3'-dicarboxylate] with the metal complex [(S,S)-1,5-diaza-cis-decalin]Cu(OH)I depending on the molar ratios in the solution. I have showed that the molar concetration of the catalyst in the solution plays an important role in the complex formation and that the ESI source spectra of...
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30

Pavlásková, Kateřina. "Hmotnostní spektrometrie v proteomice: strukturní biologie a klinické aplikace." Doctoral thesis, 2011. http://www.nusl.cz/ntk/nusl-311574.

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Mass spectrometry (MS) is a rapid, specific and very sensitive analytical method with a broad spectrum of proteomic applications such as protein identification and sequencing, 3D protein structure characterization or study of protein-protein interaction. The introduction of two ionization techniques in late 1980's that are able to ionize the large biomolecules such as proteins, oligosaccharides or nucleic acids with no or low fragmentation has started the rapidly expanding field of MS-based proteomics. The presented thesis was aimed at the application of mass spectrometric approaches to answer several proteomic questions. Firstly we have employed the chemical cross-linking in combination with MS analysis to solve the 3D structure and protein-protein interactions of three model systems: (1) homodimeric human regulatory protein 14-3-3, (2) model of 14-3-3 and regulatory domain of tyrosine hydroxylase, and (3) system of two membrane proteins, cytochrome P450 2B4 and cytochrome b5, involved in xenobiotics biotransformation. This approach works in aqueous solutions under physiological conditions and thus preserves native structure of the investigated proteins. The second part of the thesis was focused on MS identification of proteins/peptides in fungal spores of Aspergillus and Pseudallescheria...
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Stýblová, Marie. "Analýza přírodních organických barviv a pigmentů pomocí hmotnostní spektrometrie." Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-304086.

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This thesis named "Analysis of natural organic dyes and pigments by mass spectrometry" investigates the identification of selected natural organic dyes and pigments by qualitative Laser Desorption/Ionisation - Time of Flight Mass Spectrometry analysis (LDI-TOF MS). The advantage of LDI-TOF MS method is its quick and reliable identification of low molecular weight material without preparatory chemical or time-consuming modification of samples. This method can be used for the analysis of works of art or for verifying their authenticity thanks to requiring only a little amount of sample. The LDI-TOF MS was tested on 19 organic dyes and pigments (e.g. alizarin, apigenin, baicalein, flavone, xanthone, tannic acid), four exemplarily prepared lakes (alizarin, purpurin, chrysin a quercetin lakes) and lakes mixed with organic binding media. The method was also successfully applied to two samples of blue color that were taken from Josef Čapek's painting called 'Procházka' (The Walk), that was dating back to 1936.
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32

Vopelková, Alžběta. "Využití technik hmotností spektrometrie v analýze přírodních látek." Master's thesis, 2020. http://www.nusl.cz/ntk/nusl-412220.

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Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany and Ecology Candidate: Bc. Alžběta Vopelková Supervisor: doc. Ing. Lucie Cahlíková, Ph.D. Title of diploma thesis: Using of techniques of mass spectrometry in the analysis of natural compounds This diploma thesis deals with the topic " Using of techniques of mass spectrometry in the analysis of natural compounds ". The aim of the work was to create a research work and describe the profile of alkaloids in individual genera of the family Amaryllidaceae. The introduction to the theoretical part summarizes the analyzes gas chromatography (GC). Alkaloids have been classified according to their heterocyclic parts and the family Amaryllidaceae has been described. The work was based on professional texts by Czech and foreign authors. Used sources focused on the analysis of alkaloids in bulbs, or in the aboveground parts of plants in this family, using gas chromatography with mass detection (GC-MS). Key words: mass spectometry, analysis, natural compounds
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33

Kukačka, Zdeněk. "Charakterizace struktury proteinů pomocí chemického zesítění a hmotnostní spektrometrie." Doctoral thesis, 2015. http://www.nusl.cz/ntk/nusl-334650.

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Some proteins require presence of their specific ligand, cofactor or prosthetic group for their activity. Binding of this specific molecule can cause conformational changes which permit to perform their function. In some occasions the identification of conformational changes could be really challenging task. In this thesis we describe the novel approach for monitoring structural changes in proteins using chemical cross-linking and high resolution mass spectrometry and its application on model calmodulin system. It is demonstrated that analysis using isotope-labelled cross-linking agents enabled us to get insight into the structural rearrangement caused by presence or absence of the protein ligand. However, it is shown that the method has potential drawback due to limited enzymatic proteolysis. The novel approach that also makes it possible to quantify the changes in protein structure was used together with other methods for characterization of the neutral trehalase Nth1 in complex with Bmh1 protein (yeast isoform of protein 14-3-3). The results revealed that Bmh1 induce structural rearrangement of Nth1 molecule with changes within the EF- hand like motif which is essential for the activation process.
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34

Pravdová, Adéla. "Separace a identifikace lipopeptidů pomocí chromatografie a hmotnostní spektrometrie." Master's thesis, 2019. http://www.nusl.cz/ntk/nusl-397588.

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5 Abstract Protein lipidation occupies an important place in the post-translational modification group. It plays an important role in the processes of cell differentiation or synaptic transmission. Changes in the presence of lipidated proteins may in some cases indicate the appearance of human diseases such as Huntington's disease, schizophrenia, or cancer. For this reason, their analysis has become desirable, but also problematic due to its specific characteristics. This work is focused on the development of conditions for measurement of lipopeptides produced by cleavage of proteins containing lipomodification. Two separation procedures were tested, in which the aim of work was to enrich the lipopeptides and remove as many other molecules as possible from the samples. The first test method - phase interface separation, using water and chloroform, was able to concentrate the lipopeptides on the phase interface and separate some of the added unmodified peptides from the mixture. The second method of separation was a solid phase using a C18 stationary phase. As a more suitable solid phase extraction variant, elution with solutions containing acetonitrile with trifluoroacetic acid was chosen as compared to solutions containing isopropyl alcohol. With the modified elution procedure, it was possible to separate...
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35

Strmeň, Timotej. "Strukturní analýza přírodních látek s větvenými alifatickými řetězci pomocí hmotnostní spektrometrie." Master's thesis, 2016. http://www.nusl.cz/ntk/nusl-347932.

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The diploma thesis focuses on analysis of fatty alcohols with mass spectrometry. Theoretical part describes distribution, main properties, usage and analytical methods for analysis of fatty alcohols. Experimental work focuses on the search for a proper derivatisation procedure for fatty alcohols, which would enable their detection with soft ionisation techniques of mass spectrometry, as well as their structural analysis. The main aim of the structural analysis is to find the methyl branching in the fragmentation spectra of derivatives of the fatty alcohols.
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36

Vavrušová, Aneta. "Chromatografická a hmotnostně-spektrometrická analýza lipidů novorozeneckého mázku." Doctoral thesis, 2020. http://www.nusl.cz/ntk/nusl-436933.

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Lipidomics is a rapidly expanding research field that has captured extensive attention worldwide in the past few years due to the increasing awareness of the crucial roles of lipids in biological systems. The aim of lipidomics is to comprehensively analyze all lipids, to study their structure, biological function within the cell as well as interactions of lipids with other molecules. A combination of advanced analytical techniques, such as extraction, chromatography and mass spectrometry, is an effective tool for studying all aspects of lipidomics. This dissertation thesis is based on two journal publications and presents application of analytical strategies based on chromatography and mass spectrometry for investigation and characterization of new lipid classes of vernix caseosa. Firstly, the applicability of nonaqueous reversed-phase liquid chromatography atmospheric pressure ionization tandem mass spectrometry (LC- APCI-MS2 ) for structural characterization of cholesteryl esters of ω-(O-acyl)-hydroxy fatty acids (Chl-ωOAHFAs) in vernix caseosa was investigated. For this purpose, a TLC chromatography method for the isolation of neutral Chl-ωOAHFAs from vernix caseosa was developed. Their general structure was established using multi-step mass spectrometric approach requiring transesterification...
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37

Křížová, Věra. "Analýza produktů reakcí ftalaldehydu s vybranými aminokyselinami." Master's thesis, 2014. http://www.nusl.cz/ntk/nusl-339149.

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This thesis focuses on analysis of reaction products of phthalaldehyde with selected amino acids using the combination of high-performance liquid chromatography with mass spectrometry. Only one product with dihydroisoindole structure is formed in the case of simple amino acids (glycine, glycine ethyl ester, alanine, α-aminobutyric acid, valine, leucine and isoleucine). Reactions of phthalaldehyde with amino acids with two amino groups (lysine, asparagine, glutamine and arginine) yield different types of compounds. Main products are formed by the interaction of both of the amino groups with one molecule of phthalaldehyde. Apart from this type of product, these reactions also result in formation of the expected analogous structures of dihydroisoindoles. Moreover, the formation of products containing one molecule of amino acid and two molecules of phthalaldehyde is not excluded. The products were structurally analysed by the use of high-performance liquid chromatography and tandem mass spectrometry. Reaction products of phthalaldehyde with α-aminobutyric acid, valine, leucine, isoleucine and lysine were isolated and further analyses such as electron ionisation with double focusing sector analyser and nuclear magnetic resonance were performed. Pieces of information resulting from the analysis of...
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Míková, Radka. "Analýza lipidů novorozeneckého mázku chromatografickými metodami a hmotnostní spektrometrií." Doctoral thesis, 2016. http://www.nusl.cz/ntk/nusl-352040.

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(EN) Vernix caseosa is a white creamy substance that covers the skin of a newborn. It is produced during the third trimester by the skin of the baby and remains there until the age of one or even two weeks. It is uniquely human. In utero, vernix protects the skin from maceration, during the birth it serves as a lubricant and after the delivery it protects the baby against infection and regulates the temperature. As vernix is produced in third trimester, prematurely born infants lack it and this may lead to, among other things, suffering from desiccation and therefore heat loss. It is important to study it thoroughly and to find a suitable substitute of vernix for the preterm infants. Vernix consists of lipids, proteins and 80 % water. This project is aimed at the lipids. Vernix is composed of 10 % of lipids. Basic analytical methods of pocessing vernix were searched. The methods of isolation, separation and transesterification have been optimized for the lipids. For separation, thin-layer chromatography has been chosen. The method of the lipid analysis of intact molecules by MALDI-TOF MS has been optimized for these lipids. The results were confirmed using fragmentation spectra and transesterification. Esterified lipids were measured by gas chromatography coupled with mass spectrometry detection....
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39

Kuchař, Ladislav. "Tandemová hmotnostní spektrometrie sfingolipidů s aplikací pro metabolické studie a diagnostiku sfingolipidos." Doctoral thesis, 2013. http://www.nusl.cz/ntk/nusl-328211.

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In recent years, mass spectrometry (MS) become the dominant technology in lipidomic analysis and widely influenced research and diagnosis of diseases of lipid metabolism, e.g. lysosomal storage disorders (LSD) characterized by impairment of the lysosomal functions. Defects in lysosomal processing of sphingolipids SFL belong to the category of sphingolipidoses. This condition has severe and even fatal clinical outcome. The primary aim of this work was to establish quantitative and qualitative methods of SFL analysis useful for research and diagnosis of LSD. At first, semisynthesis of mass labeled lipid standards utilizing immobilized sphingolipid ceramide N-deacylase was performed. Established methods of quantitative analysis were then used to prove the increased excretion of urinary SFL in LSD with characteristic storage in the kidney. Determination of excreted urinary SFL was found useful for differential diagnosis of prosaposin and saposin B deficiences for which routine enzymology is failing. MS also enabled monitoring of individual molecular species (isoforms) of SFL, which led to the finding that their urinary pattern is changing in some LSD. This resulted in the development of new screening method in dry urinary samples based on isoform profile evaluation. Another MS application referred to...
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Vaňátková, Petra. "Využití hmotnostní spektrometrie a dalších analytických technik pro analýzu rheniových komplexů." Master's thesis, 2016. http://www.nusl.cz/ntk/nusl-352472.

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Rhenium complexes coordinated with suitable organic ligand gain increased interest in radiopharmaceutical medicine. Besides suitable radiological properties given by a metal ion itself, detailed knowledge of overall chemical properties of formed complexes, namely their exact structures, chemical stabilities and possible degradation pathways are essential pre-requisites for their clinical application. Selected rhenium complexes with pyrogallol 2,3-dihydroxynaphthalene and catechol as strongly bound ligands were prepared by a reaction of tetrabutylammonium tetrachlorooxorhenate with twofold molar excess of ligand in presence of various amount of triethylamine. The structures of formed complexes and their consequent reaction products were estimated by means of mass spectrometry with electrospray ionization. The kinetics of reactions in course of complex formation and consequent decomposition were primarily followed by UV- Vis absorption spectra measurement, complemented by single or continuous electrospray mass spectrometry analyses. Optimized HPLC and CZE procedures were utilized for monitoring of the composition of reaction mixtures in course of Re complex formation and for purity check of prepared complexes. Semi-preparative HPLC mode was succesfully utilized for isolation and final purification of...
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41

Brůhová, Michalčíková Regina. "Nové metody hmotnostní spektrometrie pro stopovou analýzu látek v lidském dechu." Doctoral thesis, 2019. http://www.nusl.cz/ntk/nusl-409264.

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This dissertation thesis summarizes results of experiments that have been carried out during my PhD studies related to the new mass spectrometric methods for trace gas analysis of human breath. The thesis is divided into the theoretical and experimental part. The chapter at the beginning of this dissertation summarizes the current research in the area of breath analysis. It is describing the common breath metabolites, benefits and challenges of the method for therapeutic monitoring and clinical diagnosis and current applications. The next chapter of the theoretical introduction describes the techniques suitable for this area of research, with a special emphasis on mass-spectrometric techniques (in particular the selected ion flow tube mass spectrometry, SIFT-MS, method that allows accurate quantification of trace gases and vapours in humid air/human breath). All these parts are elaborated via the scientific literature review. The following chapters are then directly related to my own research and describes the conducted experiment, including the results obtained. This experimental part "Results and Discussion" is divided to the individual subsections, which are conceived as the commentaries to the enclosed research papers published in peer reviewed journals. The first is the detailed step by step...
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42

Rosůlek, Michal. "Studium vlivu kofaktoru na strukturu proteinu pomocí hmotnostní spektrometrie." Master's thesis, 2015. http://www.nusl.cz/ntk/nusl-331768.

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Bacterial protein WrbA from E. coli is the founding member of a new family of FMN-dependent NAD(P)H oxidoreductases, forming a functional and structural bridge between bacterial flavodoxin and certain mammalian NAD(P)H:quinone oxidoreductase. For these reasons, protein WrbA is recently intensively studied using various analytical and computing methods. Protein WrbA participates in the protection of cells against oxidative stress, but precise function of the protein WrbA in vivo is still unknown. Protein WrbA forms multimers in solutions. In μM concentrations and at low temperature (4 řC) the protein is in the form of a dimer, with increasing temperature becomes tetrameric. Available three-dimensional crystal structure contains the information about the tetrameric form of the protein, the dimeric form has not been structurally characterized. This thesis was focused on the study of the dynamic behavior of protein WrbA in solution using methods of hydrogen-deuterium exchange and chemical cross-linking followed by mass spectrometric analysis with high resolution (FT-ICR). Behavior of the protein was monitored according to the presence of cofactor FMN. Effect of temperature and protein concentration was also studied. Hydrogen-deuterium exchange provided information about solvent accessibility and...
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Tužil, Jan. "Hledání potenciálního vazebného partnera glutamátkarboxypeptidasy II pomocí hmotnostní spektrometrie." Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-324149.

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English Abstract The incoming paradigm of the network (or systems) biology calls for a new high throughput tool for a wide scale study of protein-protein interactions. Mass spectrometry-based proteomics have experienced a great progress in recent years and have become an indispensable technology of elementary as well as clinical research. Glutamate carboxypeptidase II (GCPII; EC 3.5.17.21) is a transmembrane protein with two known enzymatic activities. Its expression is highly upregulated in some solid tumors and also in tumor-associated neovasculature in general. Nevertheless, none of the two enzymatic activities were shown to be physiologically relevant to these cells. Some facts point at a possible receptor function of GCPII, however, no specific binding partner has been found yet. In the search for potential binding partners and/or ligands of GCPII, a series of methods have been employed, including pull-down experiment, immunoprecipitation and mass spectrometry. Sample preparation and mass spectrometry data processing methodology was specifically developed in order to identify potential binding partners. As one of the outcome of that methodology, the interaction of β-subunit of F1 ATP synthase was selected for further detailed analysis as a putative ligand of GCPII.
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44

Tsybizova, Alexandra. "Přímé monitorování reakcí katalyzovaných kovy pomocí hmotnostní spektrometrie s elektrosprejovou ionizaci." Doctoral thesis, 2016. http://www.nusl.cz/ntk/nusl-351051.

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The current dissertation thesis is focused on the investigation of metal-catalyzed reactions using electrospray ionization mass spectrometry as the primary research technique. However, other gas- phase methods such as tandem mass spectrometry, infrared multiphoton dissociation spectroscopy and quantum chemical calculations have also been involved to unravel and support the findings and proposals. As organometallic chemistry is a very broad and complicated topic, this thesis is only focused on a few projects. The fist of them is dedicated to copper acetate speciation in organic solvents, the second - to the mechanistic investigation of copper catalyzed aerobic cross coupling of thiol esters and arylboronic acids, the third studied coordination and bond activation of nickel(II) - phenylpyridine complexes and the last investigated carboxylate assisted C-H activation reactions.
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45

Slavata, Lukáš. "Studium interakce mezi DNA a transkripčními faktory pomocí hmotnostní spektrometrie." Master's thesis, 2015. http://www.nusl.cz/ntk/nusl-332586.

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Transcription factors play crucial regulatory role within the cell and the entire multicellular organism. The important factor is its ability to interact with other regulatory proteins and DNA. Despite the fact that a large part of the interaction network is already documented, detailed information on the structure and dynamics of protein-protein and protein-DNA complexes is still scarce. In this thesis we focused on the possibility of studying conformational changes given by the transcription factor-DNA complex formation using the methods of structural mass spectrometry: hydrogen/deuterium exchange and chemical crosslinking. As a model, we chose a transcription factor FOXO4 which DNA binding domain is structurally well characterized both in free form and in the complex with DNA.
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46

Zdražilová, Lucie. "Analýza obsahu dolicholu v moči u pacientů s dědičnými poruchami glykosylace pomocí hmotnostní spektrometrie." Master's thesis, 2018. http://www.nusl.cz/ntk/nusl-379509.

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Dolichol is a membrane lipid, which carries monnosaccharides and glycans for N-linked protein glycosylation and glycosylphosphatidylinositol-anchor biosynthesis occuring in endoplasmic reticulum. Its structure is composed of isoprenoid units. Dolichol is present in all tissues and in most of the membrane organelles of eukaryotic cells. Recently some types of congenital disorders of glycosylation have been described as a consequence of dolichol biosynthesis and metabolism defects, which are not detectable by standard methods. The aim of this diploma thesis was to analyze dolichol content in urine and in different tissues from patients with deficiency in dolichol biosynthesis by mass spectrometry and to study the impact of these defects on energetic metabolism. Biological material for this study consisted of urine samples from 76 controls with age ranging from 1 months to 81 years, 6 patients with congenital disorders of glycosylation and 43 patients with suspicion of congenital disorder of glycosylation; samples of frontal cortex, liver, muscle and heart tissues from 2 patients with mutation in NUS1 gene and controls. Urine samples were stored at -20 řC and tissue homogenates were stored in -80 řC until analysis. Lipid fraction after extraction was separated by liquid chromatography. Dolichols were...
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Mazurová, Martina. "Struktura a interakce lidského regulačního proteinu 14-3-3: fotoafinitní značení in vitro a hmotnostní spektrometrie." Master's thesis, 2016. http://www.nusl.cz/ntk/nusl-345310.

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This work is focused on the interactome study of 14-3-3ζ protein, a regulatory protein found in all eucaryotic cells. An important 14-3-3 protein feature is the ability to bind a number of structurally and functionally distinct protein ligands. This link is usually implemented through phosphorylated serine and threonine motifs. The first aim of this work is the preparation of sufficient amount of recombinant 14-3-3ζ protein with incorporated photoactivatable analogue of methionine (foto-Met, L-2-amino-5,5- azihexan acid). The four different conditions of recombinant expression in auxotrophic E. coli B834 (DE3) strain were tested to obtain a protein with a maximal rate of photoactivatable methionine analogue incorporation into the sequence 14-3-3 protein. The second aim is to study the methionine 121, 160 and 218 participation in the 14-3-3ζ protein binding groove and finding of potential covalent bond with the phosphorylated peptide 251-266 of Raf-1 kinase (phosphorylation on Ser259). The photo-initiated cross-linking method was used (photolysis), to form a reactive biradical of methionine analogue capable to attack any amino acid residues in close vicinity (till 5Å). Finally, the products of photo-initiated cross-linking were analyzed by cross-linking reactions using MALDI-TOF MS, LC-MS and...
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48

Novák, Jiří. "Podobnostní vyhledávání v databázích hmotnostních spekter." Doctoral thesis, 2013. http://www.nusl.cz/ntk/nusl-322611.

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Shotgun proteomics is a widely known technique for identification of protein and peptide sequences from an "in vitro" sample. A tandem mass spectrometer generates tens of thousands of mass spectra which must be annotated with peptide sequences. For this purpose, the similarity search in a database of theoretical spectra generated from a database of known protein sequences can be utilized. Since the sizes of databases grow rapidly in recent years, there is a demand for utilization of various database indexing techniques. We investigate the capabilities of (non)metric access methods as the database indexing techniques for fast and approximate similarity retrieval in mass spectra databases. We show that the method for peptide sequences identification is more than 100x faster than a sequential scan over the entire database while more than 90% of spectra are correctly annotated with peptide sequences. Since the method is currently suitable for small mixtures of proteins, we also utilize a precursor mass filter as the database indexing technique for complex mixtures of proteins. The precursor mass filter followed by ranking of spectra by a modification of the parametrized Hausdorff distance outperforms state-of-the-art tools in the number of identified peptide sequences and the speed of search. The...
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49

Strmeň, Timotej. "Hmotnostní spektrometrie s chemickou ionizací za atmosférického tlaku při nízkých průtocích: konstrukční řešení a využití." Doctoral thesis, 2020. http://www.nusl.cz/ntk/nusl-436920.

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(EN) The first part of the thesis describes the ionization reactions in the APCI source in the presence (enclosed configuration) and absence (open configuration) of the ion source housing. Commercial APCI source was modified and used in enclosed, as well as open configuration. All other parameters were kept the same (including the source geometry). In the positive mode, the biggest differences were observed for non-polar analytes dissolved in aprotic solvents like toluene, chloroform and carbon disulfide. Protonated species were dominant in the open configuration, while radical cations were mostly present in the enclosed configuration. The excessive protonation in open ion source was caused by the diffusion of water vapor molecules into the ionization region from the atmosphere. Water vapor molecules were also responsible for the formation of an ion [M + 19]+ from alkynes in the open configuration. The fragmentation study confirmed that the ion [M + 19]+ was a 2-methylketone formed by the addition reaction. The formation of such artifacts can pose problems in qualitative analysis. On the other hand, the ion [M + 55]+ was observed in the enclosed ion source as a reaction product of unsaturated compounds with acetonitrile solvent molecules. Its fragmentation can be used for the double bond...
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50

Harazim, Eva. "Lipidomická analýza novorozeneckého mázku." Doctoral thesis, 2017. http://www.nusl.cz/ntk/nusl-369445.

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Methods of analytical chemistry are widely used in lipidomics. Separation techniques coupled to mass spectrometry or nuclear magnetic resonance are used very often. They make it possible to identify lipids present in the matrix in very small quantities. This work summarizes the application of modern analytical methods and instrumentation for identifying and characterizing lipids in vernix caseosa. It is shown how I contributed during the Ph.D. studies to the elucidation of the structure and characterization of unknown lipid classes followed by more detailed description of those lipid classes already identified in vernix caseosa. An integral part of my work was the application of the method enabling the localization of double bonds developed by our laboratory in triacylglycerols and 1,2-diol diesters in vernix caseosa. This analytical method is based on the formation of an acetonitrile adduct in an ionization source of a mass spectrometer enabling atmospheric pressure ionization. The complexity of the triacylglycerol class did not allow a complete characterization of the double bonds. However, the fragmentation mostly showed that double bonds up to n-12 position are present, but small peaks in some spectra also indicated double bonds at more distant positions from the chain termini. I have also...
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