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Optimization of the skin barrier model with isolated ceramides of human stratum corneum
Dulanská, Lucia ; Pullmannová, Petra (advisor) ; Zbytovská, Jarmila (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Author: Lucia Dulanská Supervisor: Mgr. Petra Pullmannová, Ph.D Title of thesis: Optimization of the skin barrier model with isolated ceramides of human Stratum corneum Stratum corneum (SC), the uppermost layer of the skin, regulates transcutaneous water loss and protects against outer conditions and harmful substances. It consists of cornified cells - corneocytes and extracellular lipid matrix, which is responsible for the barrier functions. Corneocytes are covered with covalently bound lipids creating the corneocyte lipid envelope (CLE). CLE is considered to interconnect the extracellular lipids with corneocytes and to have a templating effect. We aimed to optimize a skin lipid model simulating also the presence of CLE. The lipidic part of the model was prepared from an equimolar mixture of isolated human skin ceramides (hCer), cholesterol and free fatty acids (FFA, either protonated or deuterated) with 5 weight % of cholesteryl sulfate. hCer were extracted from the isolated human SC and purified by the column chromatography. The composition of hCer was determined by the high- performance thin-layer chromatography. The reverse-phase and normal phase silica gel particles served as the CLE...
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Dielectric Properties of Vegetable Oils for Electrical Engineering
Spohner, Milan ; Mejzlík,, Miroslav (referee) ; Mentlík, Václav (referee) ; Liedermann, Karel (advisor)
The dissertation thesis deals with the analysis of prospective environmentally compatible electrical insulating fluids for electrical engineering in relation to their chemical structure. The thesis starts with the overview of the current state of the art and of the latest trends in the use of synthetic and biodegradable natural oils. In the experimental part were studied these oils: mineral oils, rapeseed oil, sunflower oils, soybean oil, methyl oleate, peanut oil, MCT oil, castor oil and other. Dielectric properties were measured using LRC meter Agilent 4980A including dielectric liquid test fixture Agilent 16452A and also by the Novocontrol Alpha-A analyzer. Electrical properties are presented in the frequency range 10 mHz – 1 MHz range in the temperature interval 253 K to 363 K. The work goes on with the study of the suitability of individual oils for lower temperature, including the impact of the chemical structure and formulation on electrical properties.
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The influence of the quality of articulation UHMWPE inserts on the lifetime of joint replacements
Fulín, Petr ; Pokorný, David (advisor) ; Koudela, Karel (referee) ; Gallo, Jiří (referee)
This thesis focuses on the introduction with the problems of high molecular weight polyethylene (UHMWPE) in orthopedics in the first part. It discusses the history, properties and processes that lead to the failure of UHMWPE joint replacement components. The experimental part validates the hypotheses expressed. It acquaints readers with the experimental verification of the effect of different types of sterilization on the oxidative stability of laboratory prepared samples and explanted UHMWPE joint replacement components using methods of infrared microscopy, electron spin resonance, mechanical tests and tests of microhardness. Other experimental measurements on a large set of explanted components of hip and knee total joint replacements validates the hypothesis that the amount of oxidative damage affects the lifespan of joint replacements. The third part of the experimental study maps the degree of oxidative damage in different places of the hip and knee joint replacements. In the final part we experimentally demonstrate the fact that the rate of oxidative damage has an effect on supramolecular structure of the UHMWPE. From the above experiments are concluded clearly defined recommendations for clinical practice, which should lead to extend the lifespan of total joints replacements in orthopaedics....
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Evaluation of the quality of collagen samples in solid phase using circular dichroism
Ďubašák, Matej ; Žídek, Jan (referee) ; Vojtová, Lucy (advisor)
Diplomová práca sa zaoberá novou kvalitatívnou analýzou kolagénových vrstiev pomocou cirkulárneho dichroizmu v pevnej fáze. Teoretická časť opisuje kolagén a jeho sekundárnu štruktúru, spektroskopické metódy cirkulárneho dichroizmu (CD) a zoslabenej úplnej reflektancie (ATR). Experimentálna časť sa zaoberá prípravou homogénnych a transparentných kolagénových filmov a optimalizáciou objemu, koncentrácie a sušenia. Následne sa zmerala a vyhodnotila kalibračná krivka s rôznymi pomermi kolagénu a želatíny. Získaná rovnica lineárnej regresie sa použila na stanovenie obsahu kolagénu v modifikovaných vzorkách. Výsledky hodnotených modifikovaných vzoriek boli porovnané s meraniami ATR spektroskopie. Merania ATR ukázali vyšší obsah kolagénu ako CD merania. Vzorky s najnižším a najvyšším obsahom kolagénu sú pre obe metódy rovnaké. Dokazuje to, že môžme porovnávať vzorky s rôznym obsahom kolagénu navzájom, ale nemôžeme určiť presný obsah kolagénu pripojením týchto dvoch metód. Optimalizovaná metóda CD sa môže použiť na prípravu a meranie presného obsahu kolagénu vo vzorkách, najmä v rámci výroby kolagénu, aby sa dosiahla konštantná kvalita kolagénu v každom kroku výroby.
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Derivatization of the micro-samples of natural polymers with similar composition for FTIR analysis
Dudičová, Dorota ; Červený, Václav (advisor) ; Dian, Juraj (referee)
in English This master thesis is focused on verifying the possibility of optimizing FTIR spectrometric analysis of terpenic resins using derivatized (fluorinated) samples using XtalFluor-E in combination with triethylamine trihydrofluoride as an agent. Terpenic resins have very similar FTIR spectra, so for their better differentiation, they need to be derivatized to minimize the influence of overlapping spectral bands in FTIR spectra. This work aimed to create a methodology for derivatization of samples of natural polymers for the National Technical Museum in Prague, where the work was performed. Samples of terpenic resins were measured non-fluorinated by the ATR crystal method and by transmission, after fluorination, only the ATR crystal method was used. Different fluorination conditions, different times (2, 4, 6, 24 and 96 hours), the effect of sample rinsing (diethyl ether, ethylene tetrachloride) and the effect of matrix on the sample (KBr pellet) were tested. Fluorination has shown to be effective. Four hours of fluorination and the need to rinse the sample with diethyl ether were chosen as the optimal fluorination conditions. After testing the resins themselves, fluorinated samples of violin varnishes and samples of historical varnishes from harp and piano were analyzed. Their spectra before...
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DESIGN OF FIBER-OPTIC BIOSENSOR WITH NEAR-INFRARED SPECTRAL ANALYSIS
Křepelka, Pavel ; Jakubec,, Martin (referee) ; Skládal, Petr (referee) ; Mikulka, Jan (advisor)
This thesis deals with a measurement and interpretation of NIR spectra of bacterial cells and design of biosensor using this analytical technique. In the first chapter, there is introduction of current state of knowledge in the field of NIR spectroscopy in microbiology and technology of fiber optic biosensors. The summary of this chapter shows that NIR is a suitable technique for direct molecular analysis of bacteria, but it suffers from low sensitivity and insufficient interpretation of bacterial spectra. In the next part of the thesis, there is a theoretical background of spectral analysis techniques and technology of fiber optic sensors. In the practical part of this work, there is suggested the elimination of disadvantages of NIR spectroscopy in microbiology by a series of experiments used for interpretation of NIR spectra of bacteria and design of fiber optic sensor to increase sensitivity of this technique. In this work, spectral regions important for the identification of bacterial strains were determined and partially interpreted and the sensor for bacterial analysis capable of classifying strains based on 105 captured cells was designed. Therefore, the objectives of this work were fulfilled.
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Crystallization of microbial polyesters - methods and biological consequences
Liczka, Jan ; Kalina, Michal (referee) ; Sedláček, Petr (advisor)
The aim of this bachelor thesis was to test suitable methods for preparation of amorphous form of microbial polyesters and to perform model experiment to study a kinetics of crystallization of prepared polyesters. The theoretical part deals with PHA characteristics and various methods of isolating PHB granules from bacterial cells. In the experimental part, measuring techniques such as analytical centrifugation, dynamic light scattering (DLS) and Fourier transform infrared spectroscopy (FTIR) were tested to characterize the properties of PHB granules. Furthermore, an experiment was performed to isolate native PHB granules from Cupriavidus necator using lysozyme, deoxyribonuclease and cell disruption by ultrasonification. The results of the analyzes showed that the granules were either isolated amorphous only in the wet and crystallized upon drying, or that the granules were completely amorphous but not isolated from the bacterial cell.
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Optical device for breath CO2 concentration analysis
Škorpík, Daniel ; Milek, Jakub (referee) ; Čmiel, Vratislav (advisor)
This Master's thesis discusses about the measurement of the carbon dioxide concentration in breathing by an optical analyzer using infrared absorption spectroscopy. The method is described with the technical focus on individual components needed for subsequent implementation. A circuit diagram is created to produce Arduino platform devices that serve as hardware to connect and power individual parts and software to create a user environment, followed by a Bluetooth module to transmit measured data to mobile devices where real-time results are presented.
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Application of modern analytical methods for the study of selected boron coordination compounds
Hrušková, Helena ; Jelínek, Ivan (advisor) ; Dian, Juraj (referee)
This thesis is focused on the study of boron coordination compounds, specifically boron pyrogallol and 2,3-dihydroxynaphthalene ligand complexes. In the introductory part of the work are discussed the properties of boron compounds, their preparation, the possibility of separation by capillary electrophoresis and methods of structural characterization. In the first part of the thesis, the methods of preparation of complexes are discussed and for each complex the optimal yield response is chosen. The resulting products were studied by low resolution mass spectrometry. In the second part of the thesis, structures of complexes, including their modeling in the Gaussian program, were described more precisely. Furthermore, the complexes were characterized by high resolution mass spectrometry. The complexes were also studied by 11 B, 1 H and 1 H COSY NMR and IR spectroscopy. The third part was devoted to the separation of these substances from the mixture after the reaction. CE-UV and CE-MS techniques were used for this purpose. To convert the results, the separation method was developed in ammonium formate buffers that are compatible with both instruments. The equilibration between complexes and ligands was also monitored by CE-UV. A special chapter is the study of pyrogallol autooxidation by UV-VIS and...
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Low temperature plasma diagnostics by Cavity Ring-Down Spectroscopy
Kassayová, Miroslava ; Dohnal, Petr (advisor) ; Morávek, Matěj Jan (referee)
Low temperature plasma occurs in interstellar gas clouds, solar system, ionosp- here of the Earth and is used in plasmatic technologies. The study of the reactions of simple atomic or molecular ions with molecules and electrons in low temperature plasma allows better understanding of chemical processes in interstellar gas clouds and atmospheres of gas giants and gives feedback for quantum mechanical calcula- tions. It also allows to connect new facts gained via astronomical observations. The parameters of plasma (kinetic and rotational temperature of ions, their concentra- tions, etc.) may vary and many diagnostic technics are used to determine them. The aim of this bachelor thesis is to find suitable infrared transitions of N2H+ and utilize them for spectroscopical study of the electron - ion recombination of N2H+ ions with electrons. 1
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