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Rozlišení různých druhů vajec pomocí hmotnostní spektrometrie / Differentiation of different types of eggs by mass spectrometryŠvárová, Markéta January 2021 (has links)
The aim of the diploma thesis was to distinguish bird species based on the expected different protein composition of eggs and their individual components using mass spectrometry. The obtained results could be possibly used to identify the animal origin of egg materials used in works of art. For the research, components of the eggs (yolk, egg white and their mixture) of nine available bird species were collected and dried - pheasant (Phasianus colchicus), domestic goose (Anser anser domesticus), domestic duck (Anas platyrhynchos domesticus), muscovy duck (Cairina moschata), chicken (Gallus gallus f. domestica) - four different specimens, Japanese quail (Coturnix japonica), pampas rhea (Rhea americana), red ore (Alectoris rufa), speckled guinea fowl (Numida meleagris). The samples were digested by the enzyme trypsin and prepared using ZIP-TIP for the next measurements by MALDI-TOF (Matrix-Assisted Laser Desorption / Ionization - Time of Flight) mass spectrometry. The obtained data were evaluated by Principal Component Analysis (PCA). The used method showed that the most bird species can be distinguished by yolks (with an approximately 95% success rate) and more than half of the species by egg white proteins (success rate 83%) and by the egg white and yolk mixtures (success rate 80%). Two samples of...
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Využití separačních technik ve fytochemické analýze / The use of separation techniques in phytochemical analysisVíchová, Simona January 2021 (has links)
Charles University, Faculty of Pharmacy in Hradec Králové Department: Department of Pharmaceutical Botany Candidate: Simona Víchová Supervisor: RNDr. Jaroslav Jenčo, Ph.D. Title of dissertation thesis: The use of separation techniques in phytochemical analysis The alkaloid extract obtained from stems with immature capsules from Papaver rhoeas L. was subjected to a phytochemical study. The summary extract was separated into individual fractions by Flash chromatography. After performing biological tests for inhibitory activities of acetylcholinesterase and butyrylcholinesterase, the fraction PPR-11 and PPR-12 was selected. The fraction showed the highest activity against butyrylcholinesterase (95.55 ± 0.96 and 97.03 ± 0.79% inhibition of butyrylcholinesterase at 50 /g / ml). The combined PPR 11-12 fractions were purified by preparative chromatography to individual subfractions, which were purified by preparative thin layer chromatography. A monocomponent crystalline substance of alkaloid origin was obtained from the subfraction named PPR 11-12Fr # 8-A. Based on instrumental analysis, the analyte was identified as an alkaloid of the aporphine type (+)-caaverine. The inhibitory activities against acetylcholinesterase and butyrylcholinesterase for (+)-caaverine, were determined and compared with...
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Diagnostika depozice tenkých vrstev připravovaných z dimethylphenylsilanu / Diagnostics of thin layer deposition using dimethylphenylsilane monomerProcházka, Michal January 2010 (has links)
The aim of this thesis is a study of processes during organosilicone thin film deposition via plasma polymerization. Recently, thin films are the most expanding way of surface modification of materials. They are used as protective coatings, functional layers, they can increase or decrease adhesion to different compounds (e.g. water), or just improve mechanical properties of bulk materials. Plasma polymers, which are not known so long, are a modern trend in evolution of thin film deposition. They have perfect adhesion to the substrate and they are highly resistant against most of chemical compounds. Their structure is quite different from the structure of classical polymers. Recently, organosilicon compounds are used as precursors for plasma polymers because silicon built in the structure of plasma polymer allows thin film deposition on glass substrate and the organic part of monomer gives us infinite possibilities of modification. In our case dimethylphenylsilane (DMPS) was used as a monomer. Various RF low pressure discharges were used during this study. Plasma diagnostic was performed by optical emission spectroscopy of inductive coupled plasma. This method allows us to determine plasma composition during the deposition process. Thus we can predict the composition of deposited thin film according to input parameters. From relative populations of fragments we are able to find out optimal conditions for deposition process. We can also calculate temperature of particles in plasma which gives us some information about particle energies. The first part of the study deals with the identification of particles (fragments) created by fragmentation of monomer in plasma environment. We successfully identified hydrogen atomic lines of Balmer’s series in the spectra. Many rotational lines of hydrogen molecule were also detected. Atomic carbon occurred only in small amount. Much more carbon was detected in the form of CH radical. We also found some weak lines connected to atomic silicon. When we used a mixture of DMPS and oxygen, OH radical and O2+ were present in spectra. Next, optimal settings of deposition were determined for particular fragments from relative intensities of these fragments in optical emission spectra. Using this information we are able to set up the process to deposit thin films of desired composition and properties. We calculated electron temperature from intensities of hydrogen lines in Balmer’s series. Rotational temperature was obtained from CH radical intensity. Unfortunately, there was no convenient radical from which intensity we would be able to calculate vibrational temperature. All results and information obtained during the research can be used in industrial plasma polymerization processes and development of new coatings and functional thin films. Other studies on DMPS or similar monomer may also be realized to get more knowledge about processes in plasma and this thesis could serve as a basis for further research. Moreover, this study is a part of an international project. The aim of this project is to study processes during plasma polymerization both theoretically and practically. Once finished, the project and its results will be presented in scientific literature and at international conferences.
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Vliv teploty na generaci a rozklad ozónu na pevných površích / Temperature influence on ozone generation and decomposition on solid surfacesKrejsková, Eliška January 2012 (has links)
This master’s thesis is focused on a study of temperature influence on ozone generation and decomposition by chosen solid surfaces. Ozone is unstable gas that is decomposed spontaneously. This decomposition can be accelerated by various factors such as increase in temperature or reaction with other substances. The aim of this study is to determinate how fast the ozone decomposition proceeds at different temperatures and how the homogenous decomposition of ozone is accelerated by heterogeneous processes on the walls of solid materials. Currently in practise ozone is used in many areas and the finding of the rate of its decomposition can help to increase efficiency of its production and subsequent specific applications. In the theoretical part of the thesis, these points are described: important properties of ozone, possibilities of its utilization, the ozone generation, some methods of determination of the ozone concentration, ozone relationship to various solid surfaces and present theoretical knowledge about the effect of temperature on the ozone generation and decomposition. In the experimental part, the rate of the ozone decomposition in reaction tubes made of copper and iron of two different surface to volume ratios was investigated at temperatures of 10, 25, 40, 55, 70 and 85 °C. Ozone generated from oxygen was closed in the reaction tube and the decrease of its concentration during the time was observed by absorption spectroscopy. From obtained exponential dependencies, the rate constants at different conditions of this experiment were evaluated. The rate of ozone decomposition significantly increased with higher temperature. The fastest ozone decomposition took place in the iron tube of larger inner diameter (8 mm).
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Stanovení výskytu toxických prvků ve vínech / Determination of toxic elements in winesHajdučková, Iva January 2013 (has links)
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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Studium chemických procesů v atmosféře Titanu iniciovaných výbojem v elektrodové konfiguraci klouzavého obloukového výboje / Study of Chemical Processes in Titan Atmosphere Initiated by Discharge in Electrode Configuration Like Gliding Arc DischargeTöröková, Lucie January 2015 (has links)
The aim of this work is the study of plasma processes and the synthesis of organic compounds due to electric discharge generated in gas mixture corresponding to the composition of the atmosphere of Saturn's largest moon Titan. This study focuses on the mimic of Titan's atmosphere at atmospheric pressure and ambient laboratory temperature. The chemical composition of Titan's atmosphere is very similar to atmosphere of prehistoric Earth. Many articles have been published with theoretical model-research, and laboratory experiments are the pursuit of their interconnection. The main aim of thesis is the identification of synthesized gaseous organic, amino, imino and cyano compounds by use to various analytical methods such as the PTR-MS, FTIR and GC-MS. The OES and electric measurements were applied to the determination of selected electric discharge parameters. The gaseous products and radicals formed in an atmospheric discharge fed by different mixtures of N2:CH4 (0,5 up to 5 % of CH4) operated in a flowing regime at the total gas mixture flows from 50 to 200 sccm at different discharge currents from 15 up to 40 mA were determined. A part of experiments was carried out with admixtures of CO2 and hydrogen. This first part of results has been obtained using OES in dependence on the gas mixture composition and supplied power. The bands of the nitrogen second positive and the first negative systems, CN violet system and Swan system of C2 were recorded. Besides them, atomic lines H, H, and C (in the second order) were also observed. These spectra allowed calculation of rotational and vibrational temperatures. FTIR in situ analysis of the gaseous products showed presence of various nitrile compounds and hydrocarbons in all experiments. The HCN, C2H2, NH3 were the main products generated in our system. The dependences of their concentrations on various experimental parameters were measured. The other part of this work was devoted to estimate the influence of CO2 traces addition on the reactivity in the gaseous mixtures mentioned above. Besides the main products mentioned above, CO2 and CO were detected and also some more complicated oxygen molecules has been confirmed but not estimated because of FTIR spectra complexity. In the case of hydrogen traces addition into the reaction gas mixture, no other compounds were determined. Impurities of CO2 as well as hydrogen have a great positive influence on the production efficiency of the major generated compounds at all conditions. The more detailed gaseous products analyses were carried out using the in situ PTR-MS. A huge number of different molecular structures containing nitrile groups (–CN), amino groups (–NH2, –NH–, –N CH3CN > C2H5CN. Besides them, many other hydrocarbons and nitriles were detected. Presence of all compounds was studi
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Stanovení acetylcholinu pomocí LC-MS ve vzorcích mozkových mikrodialyzátů LC-MS/MS / Stanovení acetylcholinu pomocí LC-MS ve vzorcích mozkových mikrodialyzátů LC-MS/MSVrobel, Ivo January 2013 (has links)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Ivo Vrobel Supervisors: Prof. RNDr. Petr Solich, CSc; Department of Analytical Chemistry, Faculty of Pharmacy, Charles University in Prague Prof. Seppo Auriola, MSc.(Chem.) Marko Lehtonen; Department of Pharmaceutical Chemistry, School of Pharmacy, University of Eastern Finland in Kuopio Title of master's thesis: LC-MS/MS analysis of acetylcholine in brain microdialysis samples Novel fast and simple LC-MS/MS method of ACh quantification in brain microdialysis samples utilizing stable-isotope-labeled IS was developed. The chromatographic step is based on revered-phase mode of pentafluorophenylpropyl (PFPP) column. The satisfactory retention of ACh is achieved with highly aqueous mobile phase containing 0.05% of the ion-pairing agent TFA and 4% of ACN in 4 min analytical run. Ionization of ACh and IS with low background noise and tolerant towards use of TFA was performed with atmospheric pressure thermospray ionization (APTSI). The selectivity of ACh and IS detection was obtained by SRM modes of MS/MS in the linear ion trap mass analyzer. The performance of developed method was cross validated to the validated method used in the laboratory for ACh measurements. The set of microdialysis...
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Příprava a využití kyselých proteáz pro štěpení proteinů v experimentech H/D výměny. / Preparation and use of acid proteases for digestion in H/D exchange.Kukla, Jan January 2014 (has links)
- 5 - Abstract Hydrogen/deuterium exchange coupled to mass spectrometry (HX-MS) utilizes the spontaneous exchange of protein backbone amide hydrogens for deuterium atoms from solution to gain information about changes in protein structure. To localize these changes to specific areas of the protein, enzymatic digestion by aspartate proteases is used. The proteases' ability to produce small overlapping peptides and to provide full sequence coverage of the studied protein is essential for pinpointing the protein regions of interest. In this study recombinant proteases nepenthesin I (Nepenthes gracilis) and rhizopuspepsin (Rhizopus chinensis) were prepared and compared to commercially available proteases porcine pepsin A and aspergillopepsin (Aspergillus saitoi). The comparison was performed using various activity assays, where the effects of pH, temperature and denaturing and reducing agents on the activity of the proteases were studied. All four proteases were also immobilized on a polymeric resin POROS and their activity in an online HX-MS digestion setup was tested using myoglobin as a model substrate.
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Vznik nukleových bází z formamidu iniciovaný procesy o vysoké hustotě energie / Formation of nucleobases from formamide initiated by high-power density energy eventsMichalčíková, Regina January 2012 (has links)
This Master's thesis deals with determination of nucleobases in formamide samples (pure or catalyzed form) after their initiation by high-power density energy events. The theoretical part states the reader to the problems of prebiotic chemistry and acquaints him with the various theories of the origin of the nucleobases. The experimental part deals with the analysis of the samples initiated by Laser System PALS, which was used for the simulation high-power density energy events. For the identification and determination of the final products of laser plasma initiated chemical reactions in the gaseous phase of the samples was used the Fourier Transform Infrared Spectroscopy. The liquid part of the samples and the nucleobases in this part were analyzed by the gas chromatography with the mass detection.
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Zvýšení citlivosti stanovení zlata technikou elektrochemického generování těkavých specií s detekcí AAS / Sensitivity increasing of gold determination by electrochemical volatile species generation with AAS detectionVacek, Tomáš January 2013 (has links)
This thesis is focused on increasing the senstitivity of gold determination by electrochemical volatile species generation using two different types of electrolytic cells in continuous flow setting. Externally heated quartz tube atomizer was used as means of atomization and detection of gold with atomic absorption spectrometer. Generation parameters were optimized for electrolytic cell with an ion exchange (nafion) membrane. After selection of new cathode material (Cu) the carrier gas (Ar) flow rate was optimized, where an additional inlet of carrier gas was found to have possitive effect on increasing the sensitivity of determination of gold and efficiency of volatile specie transport to the atomizer. Experiments with Antifoam B showed possitive effect on generation, thus calibration was carried out for optimized experimetal conditions reaching detection limit of 0,53 mg.dm−3 . The efficiency of volatile specie transfer from liquid to gaseous phase was determined between 60 - 65 % by measuring the residual gold content in liquid waste by F-AAS method. Subsequently the effieciency of electrolytic generation of volatile gold specie with radioactive tracer isotopes and autoradigraphy was determined to 0,6 %. These methods confirmed adsorption of generated species on apparatus surface. Using ICP-MS as...
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