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Biodegradable bones implants based on iron
Hrabovský, Jan ; Zatloukal, Miroslav (referee) ; Sedlaříková, Marie (advisor)
This work deals with a current topic, which are biodegradable bone implants. These implants seem to be a suitable candidate for temporary fixations, with their gradual decomposition. An important parameter is not only the mechanical properties so that the material can withstand the load, but above all the corrosion properties and the degradation process. This work introduces the physiology of bone, trace elements and also describes current trends in the field of implants. The last part is a theoretical introduction to cross-stage processes. The practical part is focused on the preparation of iron-based samples with various dopants, subsequent annealing and analysis.
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Medicated polymer systems based on branched PLGA derivatives
Martiška, Juraj ; Dittrich, Milan (advisor) ; Kubová, Kateřina (referee) ; Kvítek, Libor (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Candidate Mgr. Juraj Martiška Supervisor doc. RNDr. Milan Dittrich, CSc. Title of Doctoral Thesis Medicated polymer systems based on branched PLGA derivatives This work is focused on the use of originally synthesized poly(DL lactic-co-glycolic acid) (PLGA) derivatives with relatively low molar mass, and linear, star, or comb architecture as promising biodegradable carriers for prolonged or targeted drug release systems. Thermal properties of these polyesters were evaluated by thermogravimetric analysis and differential scanning calorimetry. Polyesters were used for nanoparticles formulation by nanoprecipitation method, which has been optimized with emphasis on organic solvent selection, polyester concentration, phase mixing speed, and stabilizer selection. After method optimization, nanoparticles with encapsulated terbinafine, a typical drug of the BCS class II, were prepared. Multiple parameters such as particles size, polydispersity index, zeta potential, encapsulation efficiency, loading capacity, and morphology were monitored. Spherical morphology was observed using scanning electron microscopy. The hydrophobicity and the polyester concentration revealed the main impact on the nanoparticles size...
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Biodegradabilní obalové materiály
Smutný, Roman
This bachelor thesis is focused on the issue of biodegradable materials, especially with regard to packaging materials. They try to approach this issue and make information about these materials. In this work we find the distribution and history of classical packaging materials as well as the division of biodegradable materials. For better presentation of the packaging, photographs are included in the work.
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Materials for biodegradable bones based on Fe
Hrabovský, Jan ; Vondrák, Jiří (referee) ; Sedlaříková, Marie (advisor)
The thesis deals with biodegradable bone implants which must have good mechanical properties and also good compatibility with the human body. The thesis contains literary research in the area of bone physiology, biogenic materials and implants for the human body. The thesis focues on the selection of suitable materials for biogenic implants. It is also described the preparation of iron powder mixtures and application onto selected materials. The selected samples were subjected to thermal analysis.
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Modification of parameters of nanoparticles prepared from aliphatic hydroxyacids polyesters.
Křivková, Marie ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: doc. RNDr. Milan Dittrich, CSc. Student: Marie Křivková Title of Thesis: Modification of parameters of nanoparticles prepared from aliphatic hydroxyacids polyesters Polyesters of aliphatic α-hydroxyacids are mentioned in the theoretical part. A significant part of it is mostly devoted to the polyester PLGA. Physicochemical properties, the process of biodegradation and biodistribution are described there. Subsequently, some examples of PLGA utilization in pharmacy and medicine are mentioned. The theoretical part deals also with the method of diffusion used for nanoparticles preparation, which was used in the experimental part, and the principles of size and surface charge measurements of these nanoparticles. The crucial part of this master thesis is based upon an experiment. It is focused on various approaches to the formulation of nanoparticles out of aliphatic polyester carriers with variable molecular constitution. Polymer PLGA with linear molecule and polymers containing PLGA branched on tripentaerythritol and polyacrylic acid were used. Using the diffusion method, nanoparticles were prepared out of these carriers. The outer water-based phase was modified by use of cetrimide of different...
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Modification of parameters of nanoparticles prepared from aliphatic hydroxyacids polyesters.
Křivková, Marie ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: doc. RNDr. Milan Dittrich, CSc. Student: Marie Křivková Title of Thesis: Modification of parameters of nanoparticles prepared from aliphatic hydroxyacids polyesters Polyesters of aliphatic α-hydroxyacids are mentioned in the theoretical part. A significant part of it is mostly devoted to the polyester PLGA. Physicochemical properties, the process of biodegradation and biodistribution are described there. Subsequently, some examples of PLGA utilization in pharmacy and medicine are mentioned. The theoretical part deals also with the method of diffusion used for nanoparticles preparation, which was used in the experimental part, and the principles of size and surface charge measurements of these nanoparticles. The crucial part of this master thesis is based upon an experiment. It is focused on various approaches to the formulation of nanoparticles out of aliphatic polyester carriers with variable molecular constitution. Polymer PLGA with linear molecule and polymers containing PLGA branched on tripentaerythritol and polyacrylic acid were used. Using the diffusion method, nanoparticles were prepared out of these carriers. The outer water-based phase was modified by use of cetrimide of different...
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Bone implants based on Fe
Bachmayer, Marek ; Vondrák, Jiří (referee) ; Sedlaříková, Marie (advisor)
This thesis deals with usage of metal materials in bone implats creation process. This work also includes information about structure and attributes of bones, body fluids and content of iron in human organism. Following part of the paper deals with osteosynthesis, therefore commonly used methods of treating bone defects. Next part of this bachelor’s thesis is discussing the issue of biomaterials, biocompatibility and biodegradability of metal materials. Sample preparion procedure and description of samples, electrochemical corrosion and microscopic observation is included altogether with a pictorial documentation at the last chapters of this paper.
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Assessment of the effect of formaldehyde resin monomers on the environment
Kalčíková, Gabriela ; Doležalová Weissmannová, Helena (referee) ; Zlámalová Gargošová, Helena (advisor)
Thousand of new substances with unknown environmental effect are produced and used daily. Many of them are deliberately or by negligence released and deposited into the environment where they could undergo different transport and degradation mechanisms. They are able to affect different types of organisms, as well as humans. For this reason, the awareness of the problems, associated with pollution of all environmental compartments is growing. The environmental impact of monomer formaldehyde resins, which are produced for commercial use, on the environment were studied in this research. For the purposes of ecotoxicological evaluation samples of melamine-formaldehyde and urea-formaldehyde resin were chosen and three toxicity tests were run: acute test with measurement of inhibition of the mobility of Daphnia magna, the acute test with luminescent bacteria Vibrio fischeri and acute test with measurement of inhibition of oxygen consumption by activated sludge. For more comprehensive assessment of the impact of these substances on the environment, biodegradability was also determined. Both tested substances showed minor hazardous impact to testing organisms and it can be concluded, that these substances should not present a significant risk to the environment.
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Properties of biocomposites based on flax fibers
Pelánová, Markéta ; Obruča, Stanislav (referee) ; Přikryl, Radek (advisor)
This thesis is focused on composites, which are composed of degradable components. The theoretical part deals with composite materials, treatment of fibers and properties of composites. The purpose of this study is to create a composite consisting of polyhydroxybutyrate, which is reinforced with flax fibers with various modifications. The thesis also evaluates the effect of reinforcing fibers in the composite material on the tensile properties and hydrolytic stability and degradability of the composite in compost in laboratory conditions.
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Biodegradability of dissolved organic matter in soils of spruce swamp forests
ŽAMPACH, Ondřej
The aim of this thesis was to assess the biodegradability of dissolved organic matter in spruce swamp forest in habitats differing in dominant vegetation and water table. Sampling was conducted on three study sites located in Šumava National Park in the Czech Republic. Main hypothesis was that the presence of different dominants can modify the overall DOM quality and biodegradability.
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