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Biodegradable bones implants based on Fe
Tkáčová, Tereza ; Míka, Martin (referee) ; Sedlaříková, Marie (advisor)
This thesis writes about biodegradable bone implants based on iron. The currently used metal-based implants have disadvantage in an often need of secondary surgery intervention to remove the implant. Therefore, there is a big research of biodegradable bone implants nowadays. In this work, iron-based materials with the addition of zinc and magnesium are being investigated. The produced samples have been immersed in a solution of NaCl and simulated body fluid, SBL. Subsequently there were regularly analysed changes of corrosion potential, pH, conductivity and also weight loss was watched.
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Structure and mechanical properties of magnesium materials processed by HPT
Poloprudský, Jakub ; Němec, Karel (referee) ; Doležal, Pavel (advisor)
This thesis is focused on processing of pure magnesium by high pressure torsion method (HPT). This process belongs to the group of intensive plastic deformation methods (SPD). SPD methods are in the centre of scientific interest for several decades. Theoretical part of this thesis puts an effort to summarize basic knowledge and principles of SPD methods with extra focus on method HPT. As theoretical part continues magnesium as technical material is presented. Influence of SPD on use and properties of pure magnesium is then presented. This trend is further developed in effort to describe the effect of individual HPT process variables on the properties of pure magnesium and its alloys. Focus of practical part of this thesis is in influence of number of revolutions. Samples were processed at 1/8, 1/4, 1/2, 1, 4 and 8 turns at room temperature. Speed of process was 1rpm and applied pressure was 6 GPa. The structure of commercially pure magnesium prepared by casting and moulding were observed with focus on differences caused by input material. The structure was observed by both light microscopy and back scattered electron diffraction (EBSD), focusing on structure development, grain size and grain orientation. Compared to other works on similar topic, the emphasis here is on observing the microhardness on the vertical edge of the sample. The hardness shows a steep increase right after 1/8 of a turn. With increasing number of turns gradual homogenization of microhardness is presented accompanied by slight decrease in microhardness. No trend in microhardness relative to the distance from anvil has occurred. Structure observed with EBSD shows a bimodal character with larger grains oriented in the same direction. The three-point bending test didn’t end up as expected, and the approach to evaluation of magnesium-based HPT needs to be re-evaluated for future work. A three-point bending test was designed for the initial assessment of the basic mechanical properties of the material.
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Formulation of nanoparticles with terbinafine
Mrázková, Nikola ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Student: Nikola Mrázková Supervisor of Diploma thesis: Doc. RNDr. Milan Dittrich CSc. Title of Diploma thesis: Formulation of nanoparticles with terbinafine In the theoretical part of this diploma thesis is presented review concerning basic applications of nanotechnology in health service, characteristic of nanoparticles, their dividing and use in pharmacotherapy, especially in targeted drug transport. The focus of the thesis presented here is in experimental part. Particles of submicrom size were fabricated by the using of emusion solvent distribution method in the emulsion of o/w type. Star-like terpolymer of DL- lactic acid and glycolic acid branched on tripentaerytritole as core was used as potential drug carrier. The aim was to prepare the smallest particles as possible. The size and the size distribution were measured by the PCS method by the using of the device Zeta Sizer ZS. The impact of two from the chemical point of view different emulsifiers and two emulsion concentrations on the granulometric parameters of the prepared particles was evaluated. The stability of parameters during storage at lowered temperature and in the frozen state during the one day period after preparation was...
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Biodegradable bones implants based on Fe
Tkáčová, Tereza ; Míka, Martin (referee) ; Sedlaříková, Marie (advisor)
This thesis writes about biodegradable bone implants based on iron. The currently used metal-based implants have disadvantage in an often need of secondary surgery intervention to remove the implant. Therefore, there is a big research of biodegradable bone implants nowadays. In this work, iron-based materials with the addition of zinc and magnesium are being investigated. The produced samples have been immersed in a solution of NaCl and simulated body fluid, SBL. Subsequently there were regularly analysed changes of corrosion potential, pH, conductivity and also weight loss was watched.
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Structure and mechanical properties of magnesium materials processed by HPT
Poloprudský, Jakub ; Němec, Karel (referee) ; Doležal, Pavel (advisor)
This thesis is focused on processing of pure magnesium by high pressure torsion method (HPT). This process belongs to the group of intensive plastic deformation methods (SPD). SPD methods are in the centre of scientific interest for several decades. Theoretical part of this thesis puts an effort to summarize basic knowledge and principles of SPD methods with extra focus on method HPT. As theoretical part continues magnesium as technical material is presented. Influence of SPD on use and properties of pure magnesium is then presented. This trend is further developed in effort to describe the effect of individual HPT process variables on the properties of pure magnesium and its alloys. Focus of practical part of this thesis is in influence of number of revolutions. Samples were processed at 1/8, 1/4, 1/2, 1, 4 and 8 turns at room temperature. Speed of process was 1rpm and applied pressure was 6 GPa. The structure of commercially pure magnesium prepared by casting and moulding were observed with focus on differences caused by input material. The structure was observed by both light microscopy and back scattered electron diffraction (EBSD), focusing on structure development, grain size and grain orientation. Compared to other works on similar topic, the emphasis here is on observing the microhardness on the vertical edge of the sample. The hardness shows a steep increase right after 1/8 of a turn. With increasing number of turns gradual homogenization of microhardness is presented accompanied by slight decrease in microhardness. No trend in microhardness relative to the distance from anvil has occurred. Structure observed with EBSD shows a bimodal character with larger grains oriented in the same direction. The three-point bending test didn’t end up as expected, and the approach to evaluation of magnesium-based HPT needs to be re-evaluated for future work. A three-point bending test was designed for the initial assessment of the basic mechanical properties of the material.
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Influence of solvent on the size of polyester nanoparticles
Königová, Eliška ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
Univerzita Karlova v Praze Farmaceutická fakulta v Hradci Králové Katedra farmaceutické technologie Studentka: Eliška Königová Vedoucí diplomové práce: Doc. RNDr. Milan Dittrich CSc. Název práce: Influence of solvent on the size of polyester nanoparticles In the theoretical part of this thesis the methods of fabrication of nanoparticles and their evaluation are described. It further explores the biodegradable polymer of glycolic acid and lactic acid and in particular the nanoparticles prepared from this polymer. The main objective were the results of an experiment which explored some of the technological parameters of formulation of biodegradable particles made from terpolymer of DL-lactic acid, glycolic acid and tripentaerythritole by o/w emulsion method. The aim was to create the smallest possible nanoparticles using the standard procedure. The study sought the optimal concentration of emulsifier cetrimide. It evaluated the influence of the concentration of emulsion and the concentration of the polyester carrier and terbinafine as a model drug for the assessment of granulometric parameters of prepared particles. For an intended use of the method the storage of samples at low temperature after the addition of mannitol was granulometrically evaluated.
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Formulation of nanoparticles with terbinafine
Mrázková, Nikola ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Student: Nikola Mrázková Supervisor of Diploma thesis: Doc. RNDr. Milan Dittrich CSc. Title of Diploma thesis: Formulation of nanoparticles with terbinafine In the theoretical part of this diploma thesis is presented review concerning basic applications of nanotechnology in health service, characteristic of nanoparticles, their dividing and use in pharmacotherapy, especially in targeted drug transport. The focus of the thesis presented here is in experimental part. Particles of submicrom size were fabricated by the using of emusion solvent distribution method in the emulsion of o/w type. Star-like terpolymer of DL- lactic acid and glycolic acid branched on tripentaerytritole as core was used as potential drug carrier. The aim was to prepare the smallest particles as possible. The size and the size distribution were measured by the PCS method by the using of the device Zeta Sizer ZS. The impact of two from the chemical point of view different emulsifiers and two emulsion concentrations on the granulometric parameters of the prepared particles was evaluated. The stability of parameters during storage at lowered temperature and in the frozen state during the one day period after preparation was...
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Polymeric nanoparticles with biodegradable core and chelating polymers for medical purposes
Škodová, Michaela ; Štěpánek, Petr (advisor) ; Štěpánek, Miroslav (referee) ; Holger, Stephan (referee)
$EVWUDFW Application of radionuclides due to their unique nature is still attracting the interest of professionals from different branches of science. In this thesis, the unifying topic is the utilization of various radioactive labels on polymeric carriers for biomedicinal purposes. In the introductory part, the area of use of the investigated substances - in terms of their possible application in nuclear medicine, is presented to the reader. The experimental work is divided into three main sections dealing with synthesis and studying properties of appropriate selected polymers, their metal chelates and radiolabeling. First part of the study describes development of new strategies for labeling of polymeric carriers with radiometal cations and radioiodine, whereas in the following sections of the study synthesis and investigation of biocompatible polymer materials is discussed. New possible approaches in the diagnostics and therapy of cancer by using polymeric chelates as carriers are presented as well as the use of macroporous metal chelating polymer beads as potential therapeutics intended for radioembolization of liver malignancies and for the therapy of Wilson's disease. Investigated polymers have been shown to be non-toxic, to have good in vitro stability and to have the ability to be radiolabeled in...
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Evaluation of eight biodegradable algicides
Jančula, Daniel ; Maršálek, Blahoslav
The aim of this study was to compare the efficiency of biodegradable algicides towards laboratory cultures of algae and cyanobacteria. Toxicological effects of algicides were aslo studied on green alga Cladophora glomerata. Acording to our findings, it is necessary to regulate laboratory conditions to conditions in real ecosystem were treatment atgainst green algae should be done.
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