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Preparation of layers by plasma polymerization and their characterization
Kostyleva, Kseniia ; Trunec, David (referee) ; Mazánková, Věra (advisor)
The diploma work deals with the preparation of biocompatible hydrophilic layers from a propane-butane mixture by plasma polymerization. Subsequent characterization of the layers was performed using both biological (antibacterial tests and biocompatibility test) and physico-chemical diagnostics (SEM, OES and surface energy determination). The theoretical part presents the basic principle of dielectric barrier discharge, its use and various types, including surface dielectric barrier discharge (SDBD), which was used during deposition. Next, cell cultures, cell morphology and clarification of the term biocompatibility were described. At the end of the theoretical part, all used during the experimental part of the diagnostics were also described. In the experimental part, the procedure of deposition of hydrophilic layers and the overall apparatus, which was used during deposition, were presented. Prior to the characterization of the samples, the discharge was diagnosed using optical emission spectroscopy. Furthermore, the level of hydrophilicity of the layers and their elemental composition on the surface was determined. Biological tests for biocompatibility and antibacterial properties provided information on the viability of the cells on the layers and their antibacterial effects.
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Deposition and optical properties of thin films and layered structures by PECVD
Kucharčík, Jan ; Boušek, Jaroslav (referee) ; Čech, Vladimír (advisor)
Thesis in theoretical part is focused on the principle of spectroscopic ellipsometry and formation of thin films by plasma-enhanced chemical vapor deposition (PECVD). In the experimental part we describe the deposition system, ellipsometer and mathematical evaluation of ellipsometric data, materials used for film formation and processing of the samples. Single-layer and multilayer structures of polymeric materials were prepared. We revealed that the optical properties of thin films are independent of film thickness. We also described the effect of the effective power and deposition gas mixture on optical properties of thin films.
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Deposition of plasma polymer films
Malá, Michaela ; Brablec, Antonín (referee) ; Čech, Vladimír (advisor)
This bachelor thesis is focused on the characterization and preparation of thin polymer layers deposited by plasma-enhanced chemical vapor deposition on silicon wafer. The main part of the work is a literature review about the plasma polymerization and methods of characterization of thin polymer layers. In the experimental section were prepared thin layers of polymer from the monomer vapor of tetravinylsilane. Prepared thin films were characterized by microscopic and spectroscopic techniques. The physical and chemical properties of deposited films were studied with respect to the deposition conditions in low-temperature plasma.
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Plasma chemical deposition of thin polymer layers based on 2-ethyl-2-oxazoline and their diagnostics
Podzemná, Erika ; Horák, Jakub (referee) ; Mazánková, Věra (advisor)
Medical devices are often subject to the colonisation of bacteria, making it a prerequisite for infection in the patient's body. To prevent biofilm, the medical device can be covered with a thin layer of polymeric substance that has the ability to prevent biological fouling. In this work, was selected 2-ethyl-2-oxazoline as a precursor for the formation of thin polymer layers. In general, the oxazoline group is known for its antibacterial and biocompatible properties, which is the reason for choosing this substance. The main objective of this thesis was the deposition of thin polymer films, which are based on 2-ethyl-2-oxazoline, in surface dielectric barrier discharge under atmospheric pressure. The principle of thin layer formation on a teflon substrate is plasma polymerization. The preparation of the layers was followed by their characterization by several methods. Their physical and chemical properties were studied using SEM, FTIR, and by measuring the contact angles of the surface of the layers. Furthermore, the processes that take place in plasma, when there is an interaction of electrons and ions with the monomer molecule, were investigated. Ion mobility spectrometry and the crossed-beam ionization method were used for this measurement. The layers were also tested for their antibacterial and cytocompatible properties.
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Deposition and diagnostics of plasmachemical prepared thin polymer layers based on 2-methyl-2-oxazoline
Podzemná, Daniela ; Slavíček, Pavel (referee) ; Mazánková, Věra (advisor)
The deposition of thin polymer layers, which are antibacterial and cytocompatible at the same time, is one of the solutions to prevent infection when using biomaterials in biomedical applications. The formation of layers based on plasma polymerization in the surface dielectric barrier discharge, which was used in the presented work, seems promising in terms of time and financial simplicity. When we use the plasma polymerization method, it should be possible to create a layer containing such functional groups that will have the ability to repel unwanted bacterial contamination. The analyte used in this work to form such layers is the monomer 2-methyl-2-oxazoline. Plasma polymerization of this substance produces polyoxazolines, which are known for their antibacterial and cytocompatible properties. Part of the work also deals with polytetrafluoroethylene, which in our case is substrate for deposition. The subject of the experimental work was the subsequent characterization of the layers using biological diagnostic methods, which were antibacterial tests and cytocompatibility tests in vitro. The physico-chemical properties of the layers were investigated using SEM, FT-IR and the surface free energy determination method. The experimental part also included the study of interactions of electrons and ions with molecules taking place in the plasma.
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In-flight modification of nanoparticles by chemically active plasma
Libenská, Hana ; Hanuš, Jan (advisor)
Title: In-flight modification of nanoparticles by chemically active plasma Author: Hana Libenská Department: Department of Macromolecular Physics Supervisor: Mgr. Jan Hanuš Ph.D., Department of Macromolecular Physics Abstract: This diploma thesis is focused on a fabrication of the iron nanoparticles using the gas aggregation source with a planar magnetron and their in flight modification by chemically active plasma. The modification of the nanoparticles is based on a radiofrequency glow discharge, that takes place right after the nanoparticles flew out of the gas aggregation source. Nanoparticles are prepared in an argon atmosphere in which a small amount of the n-hexane has been admixed. This n-hexane impurity caused an increase in a deposition rate and higher time stability. The modification takes place in a glow discharge containing a pure argon, or in the mixtures of argon with n-hexane, ethylendiamine, hydrogen or nitrogen. Prepared nanoparticles were characterized using the X-ray photoelectron spectroscopy, scanning and transmission electron microscopy, X-ray diffraction and other techniques. The main aim of this work was to study the influence of the additional discharge on the iron nanoparticles. The chemical composition of the nanoparticles was measured immediatelly after their deposition without...
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Preparation of layers by plasma polymerization and their characterization
Kostyleva, Kseniia ; Trunec, David (referee) ; Mazánková, Věra (advisor)
The diploma work deals with the preparation of biocompatible hydrophilic layers from a propane-butane mixture by plasma polymerization. Subsequent characterization of the layers was performed using both biological (antibacterial tests and biocompatibility test) and physico-chemical diagnostics (SEM, OES and surface energy determination). The theoretical part presents the basic principle of dielectric barrier discharge, its use and various types, including surface dielectric barrier discharge (SDBD), which was used during deposition. Next, cell cultures, cell morphology and clarification of the term biocompatibility were described. At the end of the theoretical part, all used during the experimental part of the diagnostics were also described. In the experimental part, the procedure of deposition of hydrophilic layers and the overall apparatus, which was used during deposition, were presented. Prior to the characterization of the samples, the discharge was diagnosed using optical emission spectroscopy. Furthermore, the level of hydrophilicity of the layers and their elemental composition on the surface was determined. Biological tests for biocompatibility and antibacterial properties provided information on the viability of the cells on the layers and their antibacterial effects.
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Plasmachemical preparation of polymer layers based on 2-ethyl-2-oxazoline and their diagnostics
Podzemná, Erika ; Menčík, Přemysl (referee) ; Mazánková, Věra (advisor)
The bachelor’s thesis deals with deposition of thin polymer layers on 2-ethyl-2-oxazolin basis in a dielectric barrier discharge in a nitrogen atmosphere. Polyoxazolines are characterized by good antibacterial effects in general, which make them a suitable material for medical applications. After preparing of the layers. Their properties were studied using three methods. The first were antibacterial tests, which unfortunately did not confirm the above written properties. Furthermore, the free surface energy of the layers, from which it could be inferred that the surfaces were hydrophilic, was determined by measuring contact angles. The scanning electron microscopy showed the surface of the layers as well as the elemental composition thanks to the connected X-ray detector.
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Polymer layers prepared on the basis of 2-methyl-2-oxazoline by plasmachemical method and their diagnostics
Podzemná, Daniela ; Kozáková, Zdenka (referee) ; Mazánková, Věra (advisor)
The main topic of this bachelor thesis was preparation of 2-methyl-2-oxazoline-based thin polymer layers. These layers were prepared by plasma polymerization in a dielectric barrier discharge in an inert nitrogen atmosphere. In experimental part polyoxazoline layers were characterized using several diagnostic methods. The first one was study of layers surface using scanning electron microscopy, next was determination of contact angles and subsequent determination of free surface energy. Antibacterial properties were also investigated by antibacterial tests using a bacterial culture of Staphylococcus epidermidis.
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