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Application of thin layer chromatography (TLC) for fractionation of humic substances.
Hegrová, Nela ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
The main aim of this Bachelor thesis was to suggest and optimize a method of fractionation of organic matter of humic substances using thin-layer chromatography (TLC). HS Pahokee Peat standards have been characterized by thermochemical and spectrometric techniques such as thermogravimetry, elemental analysis, UV-Vis and Fourier-transform infrared spectrometry. Molecular absorption spectrometry in the ultraviolet and visible range of electromagnetic radiation and steady-state fluorescence spectrometry were used for physicochemical characterization of organic fractions. Using fluorescence spectrometry, humic substances were found to be composed of fluorophores of humic and non-humic (protein) character. Organic fractions corresponding to the humic fluorphores were characterized by a higher aromaticity, average molecular weight and higher content of oxygen substituents on the aromatic nucleus. In contrast, the organic fractions corresponding to the protein constitutional units were distinguished by low values of the humification index. These tell us about microbial origin of these organic substances during the genesis of HS Pahokee Peat.
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Effect of catalystic system on the structure of E/P copolymers
Kolomazník, Vít ; Kratochvíla,, Jan (referee) ; CSc, Zdeněk Buráň, (advisor)
Thesis is focused on structural study of ethylene-propylene copolymers (E/P copolymers) produced by gas phase polymerization. Goal of work was to determine the effect of used catalysts on the distribution of ethylene units in the resulting material. Three E/P copolymers were prepared on commercial Ziegler Natta catalysts with diether or phthalate based internal donors. The copolymers were fractionated according crystallization ability and molar mass. Next, the mass content and the distribution of the ethylene units in the copolymer were determined in each fraction by nuclear magnetic resonance (NMR). Together with other structural analytical methods, phthalate internal donor has been found to produce ethylene blocks under certain conditions, while the diether ID lacks this ability.
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Formulation and testing of rifampicin-loaded branched polyesters nanoparticles
Balciarová, Andrea ; 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: Andrea Balciarová Title of Thesis: Formulation and testing of rifampicin-loaded branched polyesters nanoparticles In presented thesis, the main attention in theoretical part is focused on nanoparticles for targeted drug delivery, their types, structure and carriers used for their preparation. Moreover, in this part there is an overview of physicochemical characteristics and preparation methods of polymeric nanoparticles applicable in formulation of pharmaceutical products. The experimental part is concerned on studying the influence of the concentration of biodegradable polymers, the presence of cationic surfactants and rifampicin as model drug substance on nanoparticles΄ size and zeta-potential. The main attention is given to nanoparticles decoration with anionic biopolymers, hyaluronic acid and xanthan gum. The simple method of preparation which is usable in nanosystems formulation that influence biological functions purposefully was tried and tested in different contexts.
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Formulation and testing of rifampicin-loaded branched polyesters nanoparticles
Balciarová, Andrea ; 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: Andrea Balciarová Title of Thesis: Formulation and testing of rifampicin-loaded branched polyesters nanoparticles In presented thesis, the main attention in theoretical part is focused on nanoparticles for targeted drug delivery, their types, structure and carriers used for their preparation. Moreover, in this part there is an overview of physicochemical characteristics and preparation methods of polymeric nanoparticles applicable in formulation of pharmaceutical products. The experimental part is concerned on studying the influence of the concentration of biodegradable polymers, the presence of cationic surfactants and rifampicin as model drug substance on nanoparticles΄ size and zeta-potential. The main attention is given to nanoparticles decoration with anionic biopolymers, hyaluronic acid and xanthan gum. The simple method of preparation which is usable in nanosystems formulation that influence biological functions purposefully was tried and tested in different contexts.
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Assessment of phosphorus associated with Fe and Al (hydr)oxides in sediments and soils
JAN, Jiří
The established fractionation scheme of Psenner and Pucsko with consecutive BD and NaOH steps was shown to be ineffective in distinguishing between the stable crystalline (hydr)oxides and their more active amorphous and poorly crystalline forms. These forms highly vary in their ability to sorb P and thus in their ecological significance. Dissolution kinetics of the Fe and Al minerals were performed using both the BD and NaOH extraction solutions. The results were applied to modify the original fractionation scheme for better quantification of P associated with active Al and Fe (hydr)oxides, and better estimation of the amounts of these Fe and Al forms in soils and sediments.
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Fractionation and molecular organization of humic acids
Chytilová, Aneta ; Enev, Vojtěch (referee) ; Klučáková, Martina (advisor)
Humic acids are part of the natural organic matter occurring all around us. The aim of this thesis is to study the molecular organization, conformation of humic acids in aqueous solutions, that always raise a number of questions. For a long time, the scientists all over the world argue, if humic acid are polymers, micelles or supramolecules. Over time, thanks to new technologies, their opinions are moving away from a polymer model and tend rather to supramolecular arrangement of humic acids. Studying humic complex systems is not easy, because they are polydisperse and heterogeneous, which significantly complicates any characterization. Moreover, its molecular organization is affected by many factors such as e.g. pH, ionic strength and etc. For the study of the conformation of humic acids, concentration series of IHSS (International humic substances asociation) Leonardite humic acids stamdards in four different mediums were prepared: 0,1 M NaOH, humic acids in water with pH modified to 12 (basic medium), 0,1 M NaOH + 0,1 M HCl, 0,1 M NaCl (neutral environment). Furthermore it has been performed the fractionation of humic acids for the purpose of simplifying the complicated structure. Prepared concentration series were characterized with several analytical methods such as ultraviolet and visible spectroscopy, dynamic light scattering, electrophoretic light scattering, microrheology, gel permeation chromatography, potentiometric pH determination and direct conductometry. Diploma thesis is built on the previous bachelor thesis in which different sample of humic acids was studied. The measured results indicate that the studied systems show supramolecular behavior and in some cases are subject to aggregation into larger units (micelles).
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Utilization of Diffusive Techniques in Study on Reactivity of Biocolloids
Kalina, Michal ; Maršálek, Roman (referee) ; Mráček, Aleš (referee) ; Klučáková, Martina (advisor)
The main aim of this thesis is the utilization of simple diffusion techniques for the study on transport properties of copper ions in the systems containing humic acids with respect to the other parameters, which can affect the process (the structure of diffusion environment, the interactions between transported specie and diffusion matrices, selective blocking of binding sites of humic acids). The first part of experimental works was focused on characterization of studied materials (humic acids, humic sol and humic hydrogel). The main part of the thesis was dealing with the optimization of simple diffusion techniques, which were suitable for the study on transport of copper ions in matrices containing humic acids, taking into account the mutual interactions between studied components in the system. The obtained diffusion characteristics were compared to the data determined using sorption experiments. Consequently, the minor goal of the experimental works of this thesis was also the assessment of the influence of basic physico-chemical parameters of studied materials on transport phenomenon.
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The radio therapy process planning
Slavíček, Tomáš ; Kolářová, Jana (referee) ; Hrozek, Jan (advisor)
This thesis aims to bring reader to the problems of radiotherapy, to give him an overview of basic principles and methods used to treat patients with cancer by ionizing radiation. The first part is devoted to the physical description of radiation and means of quantification. Interactions of radiation with matter are discussed next following with characterization of radiation effects on living cells and tissues. In the next part there is a description of the devices used in the treatment by ionizing radiation and an explanation of the various acts of patient's preparation from the target localization to irradiation. The final chapter describes created program with a graphical environment, which includes the key elements of commercial planning systems for the creation of the irradiation plan. This program uses real CT images and provides the user a basic idea of creating radiotherapeutic plan. The user has several functions for creating and optimizing the plan. The output of the program is a graphical representation of the spatial distribution of dose in the patient's body.
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