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The influence of simulated body fluids on the apatite production
Horváthová, Lenka ; Beranová, Denisa (referee) ; Bartoníčková, Eva (advisor)
This bachelor thesis deals with the interaction of various simulated body fluids with ceramic biomaterials. It includes fluid preparation, sample preparation and subsequent analysis of their interaction. Individual samples of biomaterials were exposed to a simulated body fluid for a certain amount of time. After this time, a change in the calcium and phosphorus content of the solutions was determined. At the same time, an electron microscope analysis of sample surface was performed where the dependence of calcium and phosphorus changes was demonstrated. Electron microscopy analysis revealed the formation of new phases on the surface of the studied materials.
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Silicon substituted calcium phosphate based bioceramic scaffolds
Karkuszová, Karina ; Šťastná, Eva (referee) ; Novotná, Lenka (advisor)
The theoretical part of this bachelor thesis summarizes the current state of knowledge of bioceramic materials based on calcium, phosphorus and silicon. More specifically, it focuses on calcium phosphates, the demands placed on them, the porosity of 3D foams, and biological properties such as biodegradation and bioactivity. 3D bioceramic calcium phosphate foam doped with silicon appears to be a suitable material for use in biomedical applications. It is the silicon that plays a role in the development of healthy bone and the formation of new tissue. Silicon substitutions are important in the field of investigation because they improve the bioassay of phosphate calcium. In the experimental part, calcium phosphate powders were first prepared by the hydroxyapatite and silica fusion reaction. Selected powder contents were 0; 0.1; 1, 2.5, 5, 10 and 20 wt.% SiO2. The samples were sintered at 1100 °C, 1200 °C and 1300 °C. The second part consisted in the preparation of 3D foams by direct penetration with polyurethane and the subsequent characteristics of phase composition, solubility and bioactivity. Bioceramic foams had a highly porous structure. For 42 days, sample behavior in Tris-HCl and simulated body fluid (SBF) was monitored. The results of the experiment have shown that the samples are bioactive and silicon substitution increases phosphate calcium solubility. Therefore, these materials are potentially useful for biomedical applications
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Fabrication of dental glass-ceramics
Hasalíková, Tereza ; Dlabajová, Lucie (referee) ; Bartoníčková, Eva (advisor)
This bachelor´s thesis deals with the study of glass-ceramic materials and their use in dentistry. Nowadays, studies are placed on health harmless of the material, the biological ability to adapt to the host tissue, mechanical properties, affordability, easy and fast production, aesthetics and quick recovery of the patient. The theoretical part of the work deals with various materials from various input materials used for dental substitutes. Special attention is paid to glass-ceramic and ceramic biomaterials, their preparation, heat treatment and health testing. The experimental part deals with the preparation of powder materials by the sol-gel method. Of the larger number of samples, those were selected for gelation and showed good XRD and heat microscopy results. The selected samples were subsequently subjected to heat treatment to form a glass ceramic material. The products were characterized by XRD phase composition in terms of phase temperature behavior by TG-DTA analysis, heat microscopy and SEM morphology analysis of prepared particle.
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Rheology of collagen hydrogels and its nanocomposites
Voldánová, Michaela ; Vojtová, Lucy (referee) ; Jančář, Josef (advisor)
This bachelor thesis deals with the phenomenological description of the rheological behavior of pure collagen I and its nanocomposites with addition of hydroxyapatite in four concentrations. Measurements were performed on a rheometer in the configuration cone – plate for a range of shear rates from 0 s-1 to 100 s-1 under defined conditions. At 4 °C, the collagen in samples of a specific composition remains dissolved; collagen retains his native character and the precursors of hydrogel are in the liquid state. By heating the aqueous solution of collagen with neutral pH leeds to spontaneous crosslinking process into fibrillar structure. At 37 °C, fibrils grow into the gel structure, however, the rate of its formation is dependent on the amount of collagen fibers. The measured data are processed in the form of flow and viscosity curves, from which the rheological behavior of the sample or structural and transformational changes in response to mechanical stress and temperature changes are evaluated and compared. This knowledge can be used to manipulate with hydrogels. Generally, it can help as a basis for further development of collagen, its interaction with HAP and factors influencing their stability or effectiveness.
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Stents and their applications in medicine
Sokl, Antonín ; Němec, Karel (referee) ; Molliková, Eva (advisor)
The aim of this bachelor thesis, which deals with types of stents and their use in medical area, is the provision od detailed reserches of the most frequently used biomaterials, namely details of metals, ceramics, polymers and composites, considering the suitability of their use for the production of substitutes for particular human body structures. The introductory chapters are devoted to external and internal fixation for fractures, dental implants and replacement of renal function. The following chapters deals with stents and their possible variations, especially the chapters are about esophageal stents, prostatic stents and ureteral stents. The final part of this thesis contains a detailed definition of coronary stents, their functional and shape modifications.
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Characterization of collagen from different animal tissues
Mikulíková, Zuzana ; Drábková, Michaela (referee) ; Márová, Ivana (advisor)
The aim of the proposed diploma thesis is to optimize the procedure of collagen isolation from animal tissues and methods for molecular characterization of isolates. In experimental part, isolations of collagens from animal tissues (chicken, hen, carp, and pork skin) were performed. Total protein concentration was determined by Biuret method and by TNBSA method. Both methods were used also in order to study physiological and thermal stability of the isolates under model conditions. Isolated collagens were characterized at molecular level using PAGE–SDS and microfluidic electrophoresis. Further, amino acids composition and microelement content were analyzed. Finally, the stability of isolated collagens in several types of simulated physiological and pathological conditions was tested too. During isolation relatively sufficient collagen yields were obtained (about 15 % of purified collagen per original mass of biological material). In all analyzed tissues Type I collagen was found. Thermal stability of individual samples differed according to biological source type and tissue age. Viscosimetry measurements confirmed higher stability in collagen samples of older animals. Collagenase exhibited the lowest degradation effect to bovine collagen, while selected mixed microbial hydrolases differed according to enzyme preparative type. Incubation of collagen isolates with selected human pathogens confirmed higher resistance of bovine collagen to biofilm formation when compared with the chicken one.
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Study of some modified colagen biomaterials
Zouharová, Lucie ; Drábková, Michaela (referee) ; Márová, Ivana (advisor)
The aim of the presented work is the study and biochemical characterization of some modified collagen materials (prepared on Institute of Material Science, Faculty of Chemistry, BUT), optimalization of collagen isolation from various types of animal tissues and testing of isolated collagen stability. First, isolation of collagen from five different animal tissues was performed with satisfactory yields. The concentration of total proteins was measured by Biuret and Hartree – Lowry method, the concentration of free amino groups was measured by TNBSA method. Protein analysis in colllagen preparatives was peformed by vertical electrophoresis PAGE-SDS and by microfluidic electrophoretic system Experion for comparison. Further purification and separation of collagen isolates by gel permeation chromatography was tested too. To detailed characterization thermal stability of collagen specimens was performed by high performance ultrasonic spectroscopy. Biological stability of collagen was tested in model physiological conditions.
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Materials in medicine practice
Dvořáková, Tereza ; Čikl, Josef (referee) ; Molliková, Eva (advisor)
This bachelor's thesis deals with literary research on metal, ceramic and polymer materials for medical applications. The history of these materials, their properties and material requirements are described in the first part. Further, the most often application areas of fixators and soft or hard tissue replacements are introduced. This thesis is ended by introducing a perspective science filed, which is a tissue engineering.
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Biokompozitní materiály v nábytkářství
Kopecká, Magdaléna
This bachelor thesis deals with the issue of using biomaterials as an alternative substitute for non-renewable materials and raw materials to ensure future ecological sustainability. The referential biocomposite chosen as an alternative to non-renewable materials was fungal mycelium. The basic properties of this biomaterial, the method of production, and the safety requirements are described in this thesis. Furthermore, selected tests of physical and mechanical properties were undertaken. There tests included moisture, density, swelling and determination of transverse tensile strength perpendicular to the plane of the board. All measurements were carried out in accordance with ČSN, the tests results were described and statistically verified.
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Biocompatible polymer systems for medical application
Hrochová, Michaela ; Etrych, Tomáš (advisor) ; Bárta, František (referee)
Polymer carriers for drug delivery are still an extensively studied topic in many research laboratories around the world. Polymer systems have an important role in the case of oncological diseases, where they allow to increase the therapeutic effect and significantly reduce the side effects of treatment. The present thesis is primarily focused on the synthesis of novel water-soluble biodegradable polymer systems based on N-(2- hydroxypropyl)methacrylamide enabling the treatment of solid tumors. As part of the work, four bifunctional transfer agents have been developed, which enable the direct synthesis of symmetric diblock polymers with a size of 20,000-100,000 g∙mol-1 with RAFT polymerization. The transfer agents introduce hydrolytically labile ester bonds into the structure of diblock polymers, which allow the diblock to break down into smaller fragments that can be excreted by the kidneys. The different structures of the chain transfer agents make it possible to control the breakdown of diblocks over a wide time range from 2,5 hours to 21 days. The advantages of the prepared diblock carriers are primarily the one-step synthesis, adjustable degradation time, and the possibility of modifying the end groups of the polymer chain. In the presence of bifunctional transfer agents, copolymers of HPMA...
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