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Use of thin layer chromatography for fractionation of humic substances isolated from oxyhumolite
Hegrová, Nela ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
The main goal of this thesis was to optimize the fractionation of humic substances (HS) using the method of Thin-layer chromatography, so that it can be used for physico-chemical characterization of the obtained individual organic fractions. Due to the high content of HS in the natural oxyhumolite matrix this oxidized brown coal was selected as a source of these biocolloid compounds which were isolated according to the international IHSS procedure. The sample of native oxyhumolite and oxyhumolite after extraction was characterized by thermal techniques such as thermogravimetric (TGA) and elemental analysis (EA). The above-mentioned oxyhumolite samples were further analyzed by Fourier transform infrared spectroscopy, mainly for deeper understanding of their structure in terms of an organic matrix containing HS. Characterization of isolated HSs was performed by the following thermochemical and spectrometric techniques, elemental analysis, thermogravimetry, ultraviolet and visible electromagnetic absorption (UV/Vis) molecular spectroscopy, Fourier transform infrared spectroscopy and steady-state fluorescence spectroscopy. Molecular absorption spectroscopy (UV/Vis) and steady-state fluorescence spectroscopy were used for physicochemical characterization of individual organic fractions.
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The tri-band fluorescent reader
Škrabalová, Denisa ; Čolláková, Jana (referee) ; Dostál, Zbyněk (advisor)
This bachelor thesis deals with the issue of laboratory testing and design of an optical instrument called a tri-band fluorescent reader, which is designed for fluorophores Alexa Fluor 488, Alexa Fluor 555 and Alexa Fluor 647. It contains a theoretical part with key knowledge not only in the natural sciences, such as physics, chemistry, biology, but also the current technical capabilities that are necessary for the practical part. In the practical part is drafting the objectives of the thesis, which are the measurement and evaluation of the samples examined using a monochromator, acquisition and evaluation of images using the existing system, build spectral analysis throughput, create a simulation of custom solutions and create a system engineering design. The mechanical model of the reader assembly was made after measuring the samples and the device and creating the simulation.
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Cell layer cultivation in the microfluidic system
Kachan, Ksenia ; Svoboda, Ondřej (referee) ; Chmelíková, Larisa (advisor)
The theoretical part of this thesis describes the principles of cell culture in vitro and modern in vitro models for endothelial cell layer cultivation. It also describes the principles of confocal and fluorescence microscopy. The practical part is dedicated to working with cell cultures and realization of experiment with cell cultivation in microfluidic system. Cell layer was photographed using laser confocal scanning microscope Leica TCS SP8 X during the entire experiment. For processing and analysis of the obtained images, an algorithm in the software MATLAB was proposed.
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Application of thin layer chromatography (TLC) for fractionation of humic substances.
Hegrová, Nela ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
The main aim of this Bachelor thesis was to suggest and optimize a method of fractionation of organic matter of humic substances using thin-layer chromatography (TLC). HS Pahokee Peat standards have been characterized by thermochemical and spectrometric techniques such as thermogravimetry, elemental analysis, UV-Vis and Fourier-transform infrared spectrometry. Molecular absorption spectrometry in the ultraviolet and visible range of electromagnetic radiation and steady-state fluorescence spectrometry were used for physicochemical characterization of organic fractions. Using fluorescence spectrometry, humic substances were found to be composed of fluorophores of humic and non-humic (protein) character. Organic fractions corresponding to the humic fluorphores were characterized by a higher aromaticity, average molecular weight and higher content of oxygen substituents on the aromatic nucleus. In contrast, the organic fractions corresponding to the protein constitutional units were distinguished by low values of the humification index. These tell us about microbial origin of these organic substances during the genesis of HS Pahokee Peat.
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Fluorescence probes to study the properties of hydrogel systems
Máčala, Jakub ; Venerová, Tereza (referee) ; Mravec, Filip (advisor)
This bachelors thesis is focused on possibility of selected fluorescent probes for study of properties of hydrogel systems. Chosen probes are Prodan for polarity study, HPTS for measurement of pH of the probe environment and platinum complex [2,6-Bis(2-pyridyl)fenyl-C,N,N]chloroplatinum(II) for its unique fluorescence properties and potential of energy transfer studies in hydrogel systems. Spectral properties of fluorophores were defined in selected set of solvents with different polarity with steady state fluorescence spectroscopy method. Properties of HPTS probe were also tested in buffers with different pH. Subsequently, hydrogels based on hyaluronan-septonex and dextran-SDS with incorporated fluorescence probes were prepared. Steady state fluorescence measurement of fluorophores from hydrogel were made using fluorimeter optical fibres. It was found, that probes Prodan and HPTS are suitable for study of polarity and pH of hydrogels and probably they will be able to be used for study of hydrogel with other techniques, like fluorescence microscopy, however platinum complex is, due to the low fluorescence intensity and possible quenching by polar water environment, probably not suitable for other measurements.
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Use of thin layer chromatography for fractionation of humic substances isolated from oxyhumolite
Hegrová, Nela ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
The main goal of this thesis was to optimize the fractionation of humic substances (HS) using the method of Thin-layer chromatography, so that it can be used for physico-chemical characterization of the obtained individual organic fractions. Due to the high content of HS in the natural oxyhumolite matrix this oxidized brown coal was selected as a source of these biocolloid compounds which were isolated according to the international IHSS procedure. The sample of native oxyhumolite and oxyhumolite after extraction was characterized by thermal techniques such as thermogravimetric (TGA) and elemental analysis (EA). The above-mentioned oxyhumolite samples were further analyzed by Fourier transform infrared spectroscopy, mainly for deeper understanding of their structure in terms of an organic matrix containing HS. Characterization of isolated HSs was performed by the following thermochemical and spectrometric techniques, elemental analysis, thermogravimetry, ultraviolet and visible electromagnetic absorption (UV/Vis) molecular spectroscopy, Fourier transform infrared spectroscopy and steady-state fluorescence spectroscopy. Molecular absorption spectroscopy (UV/Vis) and steady-state fluorescence spectroscopy were used for physicochemical characterization of individual organic fractions.
|
|
|
Application of thin layer chromatography (TLC) for fractionation of humic substances.
Hegrová, Nela ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
The main aim of this Bachelor thesis was to suggest and optimize a method of fractionation of organic matter of humic substances using thin-layer chromatography (TLC). HS Pahokee Peat standards have been characterized by thermochemical and spectrometric techniques such as thermogravimetry, elemental analysis, UV-Vis and Fourier-transform infrared spectrometry. Molecular absorption spectrometry in the ultraviolet and visible range of electromagnetic radiation and steady-state fluorescence spectrometry were used for physicochemical characterization of organic fractions. Using fluorescence spectrometry, humic substances were found to be composed of fluorophores of humic and non-humic (protein) character. Organic fractions corresponding to the humic fluorphores were characterized by a higher aromaticity, average molecular weight and higher content of oxygen substituents on the aromatic nucleus. In contrast, the organic fractions corresponding to the protein constitutional units were distinguished by low values of the humification index. These tell us about microbial origin of these organic substances during the genesis of HS Pahokee Peat.
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|
|
Fluorescence probes to study the properties of hydrogel systems
Máčala, Jakub ; Venerová, Tereza (referee) ; Mravec, Filip (advisor)
This bachelors thesis is focused on possibility of selected fluorescent probes for study of properties of hydrogel systems. Chosen probes are Prodan for polarity study, HPTS for measurement of pH of the probe environment and platinum complex [2,6-Bis(2-pyridyl)fenyl-C,N,N]chloroplatinum(II) for its unique fluorescence properties and potential of energy transfer studies in hydrogel systems. Spectral properties of fluorophores were defined in selected set of solvents with different polarity with steady state fluorescence spectroscopy method. Properties of HPTS probe were also tested in buffers with different pH. Subsequently, hydrogels based on hyaluronan-septonex and dextran-SDS with incorporated fluorescence probes were prepared. Steady state fluorescence measurement of fluorophores from hydrogel were made using fluorimeter optical fibres. It was found, that probes Prodan and HPTS are suitable for study of polarity and pH of hydrogels and probably they will be able to be used for study of hydrogel with other techniques, like fluorescence microscopy, however platinum complex is, due to the low fluorescence intensity and possible quenching by polar water environment, probably not suitable for other measurements.
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|
|
Cell layer cultivation in the microfluidic system
Kachan, Ksenia ; Svoboda, Ondřej (referee) ; Chmelíková, Larisa (advisor)
The theoretical part of this thesis describes the principles of cell culture in vitro and modern in vitro models for endothelial cell layer cultivation. It also describes the principles of confocal and fluorescence microscopy. The practical part is dedicated to working with cell cultures and realization of experiment with cell cultivation in microfluidic system. Cell layer was photographed using laser confocal scanning microscope Leica TCS SP8 X during the entire experiment. For processing and analysis of the obtained images, an algorithm in the software MATLAB was proposed.
|
|
|
The tri-band fluorescent reader
Škrabalová, Denisa ; Čolláková, Jana (referee) ; Dostál, Zbyněk (advisor)
This bachelor thesis deals with the issue of laboratory testing and design of an optical instrument called a tri-band fluorescent reader, which is designed for fluorophores Alexa Fluor 488, Alexa Fluor 555 and Alexa Fluor 647. It contains a theoretical part with key knowledge not only in the natural sciences, such as physics, chemistry, biology, but also the current technical capabilities that are necessary for the practical part. In the practical part is drafting the objectives of the thesis, which are the measurement and evaluation of the samples examined using a monochromator, acquisition and evaluation of images using the existing system, build spectral analysis throughput, create a simulation of custom solutions and create a system engineering design. The mechanical model of the reader assembly was made after measuring the samples and the device and creating the simulation.
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