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Effect of the number of lipid layers on the properties of thin films as skin barrier models.
Bělochová, Šárka ; Pullmannová, Petra (advisor) ; Paraskevopoulou, Anna (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Mentor: Mgr. Petra Pullmannová, Ph.D. Student: Šárka Bělochová Title of Thesis: Effect of the number of lipid layers on the properties of thin films as skin barrier models The uppermost layer of the skin, the stratum corneum (SC), primarily serves a barrier function that is essential for human survival on dry land. The SC is composed of flattened dead cells, corneocytes, which are surrounded by an extracellular lipid matrix. The composition and arrangement of SC lipids are closely related to the proper structure and function of the skin, and their disruption can lead to the development of certain skin diseases. The study aimed to determine the effect of the number of lipid layers on the properties of thin films as skin barrier models. The method used for the preparation of the models was the deposition of thin films by the Langmuir-Blodgett technique. Mono-, tri- and five-layer models were prepared. The deposited sample was a mixture simulating the composition of skin lipids and containing ceramides, cholesterol and a mixture of fatty acids in a molar ratio of 1:0.45:1. These models were then evaluated by atomic force microscopy (AFM) and Raman microspectroscopy. During the experiments,...
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The effect of ceramide structure on the behavior of thin films modeling the skin barrier.
Šustrová, Terezie ; Pullmannová, Petra (advisor) ; Kováčik, Andrej (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Student: Terezie Šustrová Mentor: Mgr. Petra Pullmannová, Ph.D. Title of Diploma Thesis: The effect of ceramide structure on the behavior of thin films modeling the skin barrier The skin barrier is essential for human survival on dry land, it is located in the uppermost layer of the skin, in the stratum corneum (SC). SC consists of corneocytes that are surrounded by an oligolamellar lipid matrix. The main components of the SC lipids are ceramides (Cer), fatty acids (FFA) and cholesterol (Chol). They are found in the SC in a ratio of 1:1:1. This ratio is essential for epidermal homeostasis. Any change in this ratio may lead to disruption of the barrier function, e.g. to the development of atopic dermatitis or psoriasis. These lipids prevent excessive loss of water from the body and the entry of undesired substances from the external environment into the body. The lipid matrix forms a typical lamellar arrangement in the skin. Lipids form structures with a long periodicity phase - LPP (d ~ 13 nm), with a short periodicity phase - SPP (d ~ 6 nm) and a separated Chol phase (d ~ 3,4 nm). The molecules are organized with each other in a lateral arrangement that can be orthorhombic, hexagonal, or...
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Local nanoparticle deposition by AFM
Vaněk, Kamil ; Havlíček, Marek (referee) ; Nováček, Zdeněk (advisor)
This thesis deals with the local deposition of rhodamine 6G and quantum dots solutions using FluidFM hollow probes implemented in the NTegra Prima AFM microscope. The NTegra Prima microscope does not officially support the use of hollow probes, and successful demonstration of the deposition capabilities of implementing hollow probes in this microscope would expand its use. The microscope could thus find applications for unique deposition experiments such as local deposition of perovskite nanocubes for nanophotonic research and others. First, the thesis provides an overview of AFM nanolithography (SPL) techniques. Their parameters, properties and applications are mentioned. In the next section, the use of SPL in the creation of structures for the field of nanophotonics is discussed in more detail. Subsequently, the NTegra Prima microscope and the implementation of hollow probes in this microscope are introduced. In the experimental part, the results of local deposition are presented. The deposition parameters used are mentioned, the procedure for the analysis of the deposited structures is described, and an evaluation of the deposition results is given. Finally, a separate subsection is devoted to the problem of cleaning of hollow probes.
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Deposition of particles released by 3D printing
Niesner, Lukáš ; Elcner, Jakub (referee) ; Bělka, Miloslav (advisor)
This thesis deals with the measurement of particles emitted by a 3D printer in a domestic environment and the subsequent CFD simulation of the deposition of these particles in a realistic model of the human airway. As a result of the work, the total and partial deposition of nanoparticles in the airway model can help to better understand the health risks.
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Preparation and characterization of nanostructured III-V semiconductor materials
Maniš, Jaroslav ; Kostelník,, Petr (referee) ; Hospodková,, Alice (referee) ; Šikola, Tomáš (advisor)
Předkládaná dizertační práce se zabývá výrobou a analýzou gallium nitridových (GaN) nanostruktur ve třech odlišných formách. V prvním případě byl zkoumám trojdimenzionální GaN ve formě nanokrystalů rostených na grafenu. Nanokrystaly byly připraveny s využitím techniky droplet epitaxy, která mimo jiné umožňuje růst nanostruktur za nízké teploty substrátu (T = 200°C). Studium se zaměřovalo jak na charakterizaci kvality připravených nanokrystalů, tak na statistický popis růstu. V dalším kroku byly připravené struktury využity pro výrobu fotodektoru citlivého na ultrafialové světlo. Výroba fotodektoru a jeho úspěšné použití slouží jako základ pro navazující výzkum. Ve druhém případě byly studovány dvoudimenzionální GaN nanostruktury, které byly rovněž připraveny za nízké teploty křemíkového substrátu. Následná analýza se soustředila na popis krystalové struktury a prvkovou analýzu, neboť byly takovéto struktury pozorovány vůbec poprvé. Další rozvoj možností přípravy těchto nanostruktur je předmětem navazujícího výzkumu. Ve třetím případě byly zkoumány jednodimenzionální GaN nanodráty připravené na safírovém substrátu. Účelem tohoto projektu bylo získání datasetu pro ověření teoretického modelu, který popisuje růst horizontálních nanodrátů. Na základě sběru a analýzy dat se podařilo modelovat růstovou dynamiku GaN nanodrátů, která byly v souladu s teoretickým modelem.
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The oxygen modification of the graphene structures for biosensors
Mikerásek, Vojtěch ; Bartošík, Miroslav (referee) ; Mach, Jindřich (advisor)
The bachelor thesis deals with the modification of CVD graphene by oxygen atoms. The theoretical part describe the structure of graphene oxide and its physical properties. Methods of production of this material and its use in biosensors are also described. The practical part describes the preparation of monolayer graphene on a silicon wafer. The main attention was paid to the oxidation of graphene by atomic oxygen and its modification in oxygen plasma. The samples were measured during process of oxidation at individual time intervals using XPS.
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Effect of Organic Additives on Electrochemical Processes Influencing Zn-Air Battery parameters
Smejkal, Jan ; Čech, Ondřej (referee) ; Chladil, Ladislav (advisor)
The diploma thesis is focused on the study of the influence of selected organic additives on the properties and morphology of zinc deposit on the negative electrode when used in zinc-air accumulators. Organic additives have been selected based on the study of literature and previously done experiments. The deposition was made on the tin plate electrodes in a solution of 6 mol/l KOH saturated with ZnO with added additives. All chosen additives were studied with a focus on the morphology of zinc deposit and with regard to their ability to suppress dendritic growth. Zinc morphology was studied by using a Tescan Vega 3 electron microscope and a Rigaku MiniFlex HR 600 X-ray diffractometer.
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Measurement and analysis of deposition of fibers from mineral wool in respiratory system
Hájek, Ondřej ; Elcner, Jakub (referee) ; Lízal, František (advisor)
This master thesis deals with inhalation of fine particles and fibres into human lungs. This is a scientific field where computer modelling is used to describe the movement of fibres and their deposition in the lungs. However, the results of these simulations must be verified experimentally. The prediction of fibres behaviour is important from a toxicology point of view where it is important to know deposition hot-spots and places where fibres could possibly cause problems. The review of the state-of-the-art is focused on the deposition of particles in human lungs followed with a chapter on fibre as a type of particle, and occupational exposure limits set by different world associations. The last theoretical chapter describes human lungs and its diseases which can evolve when limits for occupational exposure are not met. The experimental chapter consists of a description of the used experimental setup and results from an experiment together with a comparison of results with other similar experiments.
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