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Adhesion, growth and differentiation of osteoblasts and mesenchymal stromal cells on biocompatible nanomaterial surfaces
Brož, Antonín ; Hubálek Kalbáčová, Marie (advisor) ; Černý, Jan (referee) ; Kylián, Ondřej (referee)
The thesis is based on articles describing the fundamental research of carbon based nanomaterials for their possible utilization in biomedicine. The aim of this thesis was to describe the way how human osteoblasts (SAOS-2 cell line) and primary human mesenchymal stem cells (hMSC) adhere, grow and behave on surfaces made of several carbon allotropes - nanocrystalline diamond (NCD), single walled carbon nanotubes (SWCNTs) films and graphene. The utilization of carbon as the basic material promised good biocompatibility and possibility of useful surface modifications. The NCD had modified surface nanotopography (nanoroughness and nanostructuring prepared by dry ion etching). All the materials had modified surface atomic termination with oxygen and hydrogen which changes the surface electrical conductivity, surface charge and wettability. It was hypothesized that the surface termination can also influence the cell adhesion and growth. It turned out that all the studied materials were suitable as substrates for cultivation of mentioned cell types. Various nanoroughnesses of NCD surface had different effect on the cell adhesion and cell metabolic activity. Nanostructuring of the NCD influenced the formation of focal adhesions. The surface terminations of NCD and the other studied nanomaterials in...
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Dynamics of drying of sessile droplets in dependence on the surface wettability
Štefaníková, Radka ; Kylián, Ondřej (advisor) ; Shukurov, Andrey (referee)
Wettability is one of the key parameters that govern interaction between solid objects and their surrounding environment. In this work wettability of two kinds of materials was investigated - untreated and plasma treated polyether ether ketone and nanostructured C:F thin films deposited either onto a smooth substrate or on substrates seeded with nanoparticles. In the first case the main focus was given to the evaluation of dependence of wettability and water droplet drying dynamics on the plasma treated PEEK on storage time. It was found that plasma treatment induces changes in surface morphology and in chemical composition that in turn results in dramatic increase of surface wettability as well as in alteration in drying dynamics. It was shown that whereas chemical composition and wettability gradually approach properties observed on untreated PEEK, the drying dynamics, namely disappearance of the constant contact angle phase, is temporally stable. In the second case the main emphasis was given to the investigation of the effect of surface nanoroughness and its character on wettability of produced samples. It was found that when the base layer was composed from nanoparticles of the same kind, the surfaces exhibited higher values of water contact angles as compared to C:F films deposited onto smooth...
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Modification of polymeric materials by means of atmospheric plasma for biomedical applications
Kretková, Tereza ; Kylián, Ondřej (advisor) ; Hanuš, Jan (referee)
Polymeric materials are thanks to their advantageous volume properties and due to their relatively low price interesting for various applications. However, the possible use of common polymers is hampered by their low surface energy that leads to poor adhesion of subsequent coatings and limited ability to bind biomolecules. One of the strategies to increase the surface energy is modification of polymer surface by atmospheric plasma. In this study, we have investigated effect of atmospheric pressure dielectric barrier discharge generated in air on poly(ether-ether-ketone). We estimated plasma composition by optical emission spectroscopy as well as monitored temperature of the polymer during the treatment in order to verify applicability of this plasma source. Subsequently changes in morphology, chemical composition and surface energy of polymeric samples after the plasma treatment were determined. We proved that surface energy increases with increasing surface density of polar functional groups and that plasma causes changes in morphology of the studied polymer surface. We determined the etching rate of poly(ether-ether-ketone) in dependence on the supplied power. Optical properties remained unchanged indicating that also volume properties were not affected by plasma. Finally we tested the binding of...
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Deposition of Nanocomposite Thin Films
Kratochvíl, Jiří ; Kylián, Ondřej (advisor) ; Straňák, Vítězslav (referee)
Nanocomposite thin films can find application in photovoltaics, optics, fabrication of sensors, or in biomedicine. This work investigates fabrication and characterization of thin metal-plasma polymer nanocomposite films which have direct application because of their unique optical properties (e.g. SERS - Surface-Enhanced Raman Spectroscopy) or antibacterial effects (biomedicine). We fabricated metal nanoparticles either by magnetron sputtering (island growth) or by means of gas aggregation source of nanoparticles, thereby we got nanoparticles with very different morphologies. We used silver as a material for nanoparticles because of its antibacterial effects. We incorporated these nanoparticles into sputtered Nylon and sputtered PTFE (polytetrafluoroethylene) plasma polymer matrix. These two polymers have very different chemical structure and related different surface energy. First, we compared growth of nanoparticles on substrates of sputtered Nylon and PTFE. Then we compared properties of sandwich nanocomposites polymer-Ag-polymer for both types of nanoparticles and for both matrix materials. We characterized produced thin films especially with respect to their stability in water (antibacterial films), thermal stability (sterilization by heating) and stability on the open air (storage). Finally, the tests...
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Nanoclusters coatings for biomedical applications
Divín, Radek ; Kylián, Ondřej (advisor) ; Hanuš, Jan (referee)
Title: Nanoclusters coatings for biomedical applications Author: Radek Divín Department: Department of Macromolecular Physics (110. 32-KMF) Supervisor: RNDr. Ondřej Kylián, Ph.D. Abstract: The copper nanocluster films were prepared with the aid of the gas cluster aggregation source based on the principle of material sputtering from the magnetron target to the relatively high pressure of the working gas (Ar). The nanocluster films prepared in this way were subsequently overlapped with the layer of plasma polymer deposited by RF magnetron sputtering from the nylon polymer target in the atmosphere of the working gas (Ar, 2 Pa). A repetition of this procedure enabled to prepare nanocomposite layers having a multilayer character. These layers were subsequently investigated with regard to their morphology, chemical composition, surface wettability and optical properties. The chemical composition of the surface layer formed by nanocomposite films was determined by the X-ray photoelectron spectroscopy (XPS). It turned out that the chemical surface composition of prepared nanocomposites was not markedly influenced by the presence of the Cu nanoclusters. The morphology of prepared films was studied by the scanning electron microscopy (SEM) and the atomic force microscopy (AFM), which showed that the resulting...
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Ultrathin films deposited by means of magnetron sputtering and their characterization
Petr, Martin ; Kylián, Ondřej (advisor) ; Straňák, Vítězslav (referee) ; Tichý, Milan (referee)
Presented work is focused on the deposition and characterization of thin and ultrathin plasma polymer films, then also on the preparation of nanocomposites metal/plasma polymer. The characterization of plasma polymer films was partly done in-situ without exposing the samples to the atmosphere. The thickness of prepared films was measured by spectral ellipsometry, the chemical composition was measured by XPS. The morphology and optical properties of deposited films were measured ex-situ. It is shown that during the initial stages of growth the properties of plasma polymer films depend on their thickness and also on the material of the substrate. Many interesting applications were explored for prepared nanocomposites metal/plasma polymer. They can be used as superhydrophobic coatings, gradient coatings, substrates for Raman spectroscopy or as antibacterial coatings. Moreover, special optical properties of prepared nanocomposites were studied in detail. Presented work has an experimental character.
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Depozition of hydrophobic fluorocarbon coatings by plasma polymerization methods
Petr, Martin ; Kylián, Ondřej (advisor) ; Kudrna, Pavel (referee)
In this work we study the deposition of hydrophobic fluorocarbon coatings by magnetron sputtering of polymeric PTFE target. We show what is the influence of the conditions of the deposition process - the pressure in the chamber, the RF power - on the properties of the resulting CFx thin films (their chemical composition, morphology, wettability, barrier and optical properties, stability and possible bio-aplications). In this work we use a novel way to control the morphology and the chemical composition of the surface of thin films independently by using nano-particles, both metal (Pt, Cu, Al) and polymeric (C:H, Nylon). With nano-particles we can control the hydrophobicity of thin films and we can prepare super-hydrophobic films. Work has an experimental character.
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Fabrication of metal nanoclusters and their characterization
Kratochvíl, Jiří ; Kylián, Ondřej (advisor) ; Kousal, Jaroslav (referee)
Copper nanoclusters have potencial for fabrication of nanostructured surfaces, which can be used in electronics, electrotechnics, optics and in biomedical applications. To create such surfaces, it is necessary to create and characterize the nanoclusters deeply first and this is the main topic of this work. First, we found repeatable procedure to create copper nanoclusters by the gas aggregation nanocluster source. We studied homogenity of prepared surfaces by quartz crystal microbalance and optical ellipsometry, we determined conditions for deposition of homogeneous coatings. Next, we studied deposition rate in dependence on the magnetron current, pressure in the aggregation and deposition chambers. Deposition rate linearly increased with current, but in low currents it was nearly zero. Furthermore, we found maximum deposition rate for a given pressure in the aggregation chamber and determined the range of pressure in deposition chamber where it is possible to deposit thin films of copper nanoclusters. This is important for fabrication of nanocomposite surfaces. We studied also the size, shape of nanoclusters and growth of surface by scanning electron microscope. The surfaces were very porous. We measured roughness and optical absorbance where anomalous optical absorption was found. Finally, we found that...
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Diagnostics of plazma in the deposition sources using the Langmuir probes
Šedivý, Petr ; Kousal, Jaroslav (advisor) ; Kylián, Ondřej (referee)
This experimental work is concerned with measurement of elementary characteristics of plasma - potential of plasma, electron temperature and density of particles. As research methods were selected the Langmuir probes - especially the single probe. At the beginning of the thesis there are explained shortly the elementary characteristics of plasma and the procedure of determination particular parameters of the plasma from the volt-ampere characteristics of the probe. The third chapter is focused on description of the experiment, the probe, the apparatus and its control. Plasma measured within this work originated from the new hollow magnetron which will serve as future source of nanoparticles. Results of the work are focused on the description of individual parameters of the plasma in dependence on other variables such as the magnetron power, pressure of gas, spatial dependence or presence of additional auxiliary magnetic field.
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