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Biological characteristics of polysccharide based contrast agents for cancer diagnostics
Křivánková, Markéta ; Jirák, Daniel (advisor) ; Shapoval, Oleksandr (referee) ; Vannucci, Luca Ernesto (referee)
Despite all the progress made in the treatment of cancer in recent years, it is still necessary to continue with the research of more effective and specific drugs. In recent years, there has been a growing interest in personalized medicine and its application through drug delivery systems, which could help increase the specificity of cancer treatment and subsequently its effectiveness. Drug delivery systems can use different platforms for their design, whether they are liposomes, micelles, nano crystals or others. A very interesting platform for the construction of drug delivery systems are polysaccharides, which were, as carriers of contrast agents in order to effectively display tumours, characterized in this doctoral thesis. But polysaccharides are interesting for more reasons. Both by its availability, and by its biocompatibility and non-toxic character. In this doctoral thesis we deal with two types of polysaccharides conjugates with linked contrast agents for magnetic resonance and fluorescent imaging. The first type of polysaccharide is glycogen, the second is mannan. Both constructs - glycogen and mannan based, were synthesized in a version with and without polymethyloxazolin, which should prolong their circulation in the organism. Both types of polysaccharide conjugates used passive...
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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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Structure and magnetic interactions in nanomaterials with application potential
Pacáková, Barbara ; Kalbáčová Vejpravová, Jana (advisor) ; Jirásková, Yvona (referee) ; Svoboda, Pavel (referee)
The thesis is focused on the physics of magnetic nanoparticles (NPs), starting from the solution of magnetic structure, internal alignment within the single particle and role of interactions and particle structure in magnetic response of systems of the NPs. Moreover, the macroscopic arrangement of the NPs and its effect on the properties of system containing the NPs are discussed. The work brings several new results and concepts, such as the solution of magnetic structure of the ε-Fe2O3 phase, methods of proper detection and description of magnetic metal catalyst in carbon nanotubes and role of the NP arrangement and their effect on graphene placed on the top of substrates decorated with the NPs. 1
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Toxicity of nanomaterials to aquatic crustaceans
Novotná, Kateřina ; Kočí, Vladimír (advisor) ; Cajthaml, Tomáš (referee)
Nowadays, nanomaterials are broadly used for many purposes thanks to their unique properties. The production of nanoscale materials is growing rapidly. Consequently, it means a high probability of their release into the environment and there are concerns about their possible negative effects on organisms. Furthermore, the behaviour of nanomaterials might be strongly influenced by many factors and there are many different types of them, so there is still a big information gap in this field. The aim of this work is to summarize basic facts about nanomaterials and their possible toxicity, especially to the fresh-water crustacean Daphnia magna. An impact of nanoscale zero-valent iron particles is tested on this species. This material is used for remediation so it is injected directly into the environment. Concentrations of 0,1 g·l-1 , 0,5 g·l-1 , 1 g·l-1 and 2,5 g·l-1 of two products with different surface modifications were tested. It was found that the toxicity depends on the type of stabilization. EC50 was not established for NANOFER 25S (with a special surface modification) due to the maximum immobilization rate of only 30 % for the concentrations tested. However, the EC50 value for NANOFER 25 (without the special surface modification) is 0,94 g·l-1 . These results confirm that it is necessary to...
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Theoretical Investigation of Low-dimensional Magnetic Materials
Li, Shuo ; Grajciar, Lukáš (advisor) ; Frauenheim, Thomas (referee) ; Jelínek, Pavel (referee)
Low-dimensional (D) materials, such as graphene, transition metal dichalcogenides and chalcogenide nanowires, are attractive for spintronics and valleytronics due to their unique physical and chemical properties resulting from low dimensionality. Emerging concepts of spintronics devices will greatly benefit from using 1D and 2D materials, which opens up new ways to manipulate spin. A majority of 1D and 2D materials is non-magnetic, thus their applications in spintronics are limited. The exploration, design and synthesis of new 1D and 2D materials with intrinsic magnetism and high spin-polarization remains a challenge. In addition, the valley polarization and spin-valley coupling properties of 2D materials have attracted great attention for valleytronics, which not only manipulates the extra degree of freedom of electrons in the momentum space of crystals but also proposes a new way to store the information. The computational investigation of magnetic and electronic properties of low-dimensional materials is the subject of this thesis. We have systematically investigated geometric, electronic, magnetic and valleytronic properties of several 2D and 1D materials by using the density functional theory. These investigations not only theoretically show rich and adjustable magnetic properties of...
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Enzyme-triggered polymer probes for fluorescence-guided surgery of solid tumors
Horáková, Lenka ; Etrych, Tomáš (advisor) ; Kaňa, Martin (referee)
This work is focused on the synthesis of macromolecular hydrophilic polymer conjugates with fluorophores for visualization of solid tumors. These polymer probes were designed for their utilization within the image-guided endoscopic surgery, where the boundaries of the tumor tissue would be fluorescently marked after i.v. administration. Polymer carriers should provide prolonged circulation of the probe in the body and the transport of the fluorescent dye into the desired place. Polymer probes based on N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers prepared by radical copolymerization containing fluorescent dye cyanine7-NH2 (Cy7- NH2) were synthetized and evaluated. The dye was conjugated to the carrier via an enzymatically cleavable peptide linker, specifically Gly-Phe-Leu-Gly and Val-Cit-4-aminobenzylalcohol. The enzymatic hydrolysis of these polymer conjugates was studied using a model lysosomal enzyme cathepsin B. In vitro study was carried out using hypopharyngeal cancer cell line FaDu, in which the internalization of the probes into cells and accumulation in cell compartments was evaluated by the fluorescent confocal microscopy. Key words: nanomaterials, polymer probes, fluorescence, EPR effect [IN CZECH]
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Development and preparation of antimcrobial nanostructure biomaterials
Drabíková, Nela ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
The presented diploma thesis deals with the optimalisation of preparation and the preparation of combined nanostructured antimicrobial biomaterials itself. In the theoretical part, a review focused on used materials and consequently preparation of nanoparticles and nanofibers was elaborated. Furthermore, the used antimicrobial substances – curcumin and ampicillin, and the principle of cytotoxicity assay were described.In practical part the optimalisation process is described. Furthermore the safety of prepared materials and used antimicrobial substances on HaCaT cell line was tested, in order to confirm their possible further use in cosmetic and pharmaceutical industry. Great part of the thesis deals with evaluation of the antimicrobial activity of used substances and prepared combined nanomaterials on multiple microorganisms from grampositive bacteria, gramnegative bacteria and yeasts. Also the release speed of antimicrobial substances from prepared nanomaterials was determined by spectrophotometer. The amount of released ampicillin from prepared nanomaterials was determined by liquid chromatography.
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Automatisation of an experimental setup for optical spectroscopy
Hrabina, Jakub ; Gallina, Pavel (referee) ; Dvořák, Petr (advisor)
This bachelor thesis deals with the development and description of an application that enabled full automation of an experimental assembly for spectral mapping using confocal optical microscopy. It presents communication with all individual devices and explains the principle of data collection from the examined sample and their subsequent mathematical processing. The output of this application is the visualization of 2D spectral maps evaluating the intensity and position of spectral peaks, with the possibility of exporting user-friendly point spectra. In addition, the work further describes a research study of optical confocal spectroscopy with applications to nanophotonics. In addition, the functionality of the whole application is demonstrated on the spectral response of a 2D metasurface, which acts as a Bayer mask.
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Toxicity and environmental fate of nanoscale zerovalent iron
Semerád, Jaroslav
Nowadays, nanoscale zerovalent iron (nZVI) is a nanomaterial commonly used in remediation practice. Although worldwide applications of nZVI have shown its effectiveness in degradation and immobilization of a wide range of organic and inorganic pollutants, potential negative effects of nZVI on exposed organisms have not been sufficiently explored. To avoid possible environmental risks, understanding of the mechanism of nZVI toxicity and its overall effects on microbial populations indigenous to remediation sites is needed. The presented thesis summarizes current knowledge of nZVI toxicity, and, moreover, deals with the development and application of a new test for in vitro evaluation of acute toxicity caused by newly developed nZVI-based materials. Additionally, in this thesis, the risk associated with changes in the toxicity of the aforementioned materials during the aging process was examined. In the last part, the effect of several nZVI-based materials on microbial communities of a real contaminated soil was monitored and evaluated using artificial microcosms. In addition, in this part, the potential of nZVI and its derived materials in combination with a biostimulation step during nanobioremediation is outlined.
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Flexible generators of electrical energy
Tesařová, Tereza ; Holcman, Vladimír (referee) ; Tofel, Pavel (advisor)
This bachelor thesis is focused on actual research part of energy harvesting technologies – flexible electrical generators, which mean the special generating of electricity using specific flexible materials. The net charge result is affected by the incidental mechanism to transform certain energy form into electrical power and is influenced of material range, which determines what will be harnessed as a source of energy. The energy harvesting is aiming at producing alternative and efficient ways instead of harmful and strained manufacture processing.
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