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Use of thin layer chromatography for fractionation and characterization of organic matter isolated from alginite
Solanský, Pavel ; Sovová, Šárka (referee) ; Enev, Vojtěch (advisor)
This diploma thesis is focused on the study of structure and physicochemical properties of organic fractions of humic substances, which were obtained by the method of thin-layer chromatography. Humic substances, which were used in this study, were isolated from a sample of Slovak alginite based on the procedure of the International Humic Substances Society (IHSS). The following analytical techniques were selected for the characterization of isolated humic substances: thermogravimetric and elemental analysis, molecular absorption spectroscopy (UV/Vis), Fourier transform infrared spectroscopy (FTIR) and steady-state fluorescence spectroscopy. Each organic fraction of humic substances were characterized by molecular absorption spectroscopy (UV/Vis) and steady-state fluorescence spectroscopy. Using steady-state fluorescence spectroscopy, humic substances were found to be composed of fluorophores of humic and non-humic (protein) character. Organic fractions corresponding to the humic fluorophores were characterized by a higher content of oxygen substituents on the aromatic nukleus, a higher degree of aromaticity and also a higher molecular weight. The aim of this diploma thesis was to design and optimize the process of organic matter fractionation for the purpose of detailed understanding of the structure and properties of humic substances, which were isolated from the sedimentary rock alginite. Based on this, the practical applicability of the thin layer chromatography method to significantly reduce the molecular heterogenity of the studied humic substances was evaluated.
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Characterization catanionic vesicular system by HRUS
Kopřivová, Hana ; Sovová, Šárka (referee) ; Hurčíková, Andrea (advisor)
This bachelor thesis is about catanionic vesicular systems, which could serve as carriers of drugs or genes in the future. These systems are prepared from the cationic surfactants CTAB and DDAC, the anionic surfactant SDS and cholesterol, which serves as a stabilizer. In the experimental part, these vesicles were characterized by high-resolution ultrasonic spectroscopy. The behavior of systems with different percentages of cholesterol was monitored. As next, the temperature properties of the vesicles were studied using temperature scans between 10 °C and 65 °C. The density of the samples was examined by densitometry at temperatures of 25 °C and at a human body temperature of 37 °C.
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Study of interaction in biopolymer-surfactant system
Sovová, Šárka ; Mondek, Jakub (referee) ; Pilgrová, Tereza (advisor)
Interaction between biopolymer-surfactant and stability of arising complexes were investigated using dynamic light scattering method Stability of the system and interactions between native hyaluronan and cationic surfactant cetyltromethyl-amonium bromide in aqueous solution depending on preparation method were investigated. System was prepared either adding CTAB to hyaluronan causing sequential micelle’s formation, or adding hyaluronan to already formed micelles. It was found out that preparing method influences properties of arisen complexes. Molecular weight of hyaluronan has an inconsiderable effect on interaction against to concentration of hyaluronan, which influences interaction of component significantly.
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Hydrogel fantoms in ultrasonic diagnostic
Chovancová, Aneta ; Sovová, Šárka (referee) ; Hurčíková, Andrea (advisor)
This Bachelor thesis is interested in hydrogel phantoms made from gelatin, agar and agarosa. The effect of food foil on the essential properties of gel matrixes such as drying and moulding has been investigated. These properties were investigated visually and gravimetrically. The speed of prepared gel matrixes was measured using high resolution ultrasonic spectroscopy depending on concentration. In the work, I follow up on the already performed Bachelor thesis [1], where gel matrices were measured in the environment of air and water. My gel matrices are dispensed to the machine's cell in a liquid state. Depending on the material used and the method of use of the food foil, gel matrixes prepared for visual and gravimetric evaluation from agar with a concentration of 3 % and 5 % without foil and with foil on the bottom were found to have a longer shelf life than other samples with the same use of foil. Gel matrixes of all three substances and all concentrations covered with food foil are able to last up to 20 days without massive drying and mould formation. The result of measuring the relative ultrasonic velocity of the hydrogels produced was found to increase the rate of spread of ultrasound for all measured substances as the concentration increased.
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Effect of crowding agents on DNA-surfactant interaction
Sovová, Šárka ; Hurčíková, Andrea (referee) ; Pekař, Miloslav (advisor)
Tato diplomová práce se zabývá vlivem zaplňovacích činidel na interakce v systému DNA-tenzid. DNA o velikosti 4017 párů bází byla připravena polymerázovou řetězovou reakcí, jako templát byl použit plasmid pSB-E1g. Polyetylen glykol (PEG) byl použit jako zaplňovací činidlo a jeho vliv na DNA-tenzid interakce byl zkoumán experimenty založenými na fluorescenci a gelové elektroforéze. Také byl studován vliv iontové síly za použití NaBr na interakce DNA-tenzid za použití zaplňovacího činidla. Data byla vyhodnocena a evaluována v této práci. V úvahu byl brán i možný vliv polyetylen glykolu na kritickou micelarní koncentraci (CMC) tenzidu, bylo provedeno měření CMC pomocí ultrazvuku s vysokým rozlišením, avšak nebyl zjištěn žádný značný vliv zaplňovacího činidla na CMC tenzidu. Část této práce bude zahrnuta v publikaci s anglickým názvem Combined role of macromolecular crowding and cationic surfactant in efficient DNA condensation.
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Study of bulk and hydration water in hydrogel systems suitable for medical applications
Řihák, Marek ; Sovová, Šárka (referee) ; Enev, Vojtěch (advisor)
This bachelor thesis focuses on a preparation of hydrogel systems based on hyaluronan and Septonex and on a design and optimalization of quantitative analysis of hyaluronan and Septonex in a supernatant after gelation. This work compares hydrogels formed from hyaluronan of two different molecular weights. The calibration curves of hyaluronan and Septonex were used to evaluate the experimental data. The thermogravimetric analysis and Fourier-transform infrared spectroscopy were used for the characterization of properties of the samples. The utilisation of the mentioned techniques to study molecular water subpopulations was discussed according to the obtained results.
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Bioactive substances for face cream: Determination of stability of face cream incorporated with goat's milk
Dostálová, Tereza ; Sovová, Šárka (referee) ; Enev, Vojtěch (advisor)
The aim of this bachelor thesis is a stability trial of a skin cream incorporated with goat milk lyophilizates prepared in usual laboratory conditions. Firstly, the goat milk was denatured, to be further analysed via FTIR, elemental analysis and thermogravimetry. To compare the denaturation effect, measurements with native goat milk sample were performed as well. Next, an emulsion was prepared. First stability tests were performed using analytical centrifuge and the cream preparation procedure and component ratio was optimized. Stability trials were carried out at specified time intervals. Rheological properties – especially yield stress values and structure strength, determined by linear viscoelastic region and complex modulus – thermal endurance measured via differential scanning calorimetry and visual validation via optical microscopy and sample observation were tested and performed. Skin cream stability of sample stored at laboratory temperature was demonstrated, showing moderate sings of structure destabilisation. Product suitability for dry skin was proved by sensory analysis. The skin feeling was pleasant, and the cream moisturized the surface area, that it was applied to, according to evaluators. Visually, the emulsion appeared to maintain its properties during the experiment time range, it did not undergo a complete degradation of separation into two original phases, nor it was degraded, for example by mold.
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The preparation of stable nature BB creams and determination of its properties
Marčanová, Milada ; Sovová, Šárka (referee) ; Hurčíková, Andrea (advisor)
The aim of this diploma thesis was create a natural BB cream that, in addition to sufficient hydration, would protect the skin from sunlight, unify its colour tone and at the same time sufficiently cover any imperfections. After proposition a suitable recipe, it was necessary to determine the stability of the prepared BB creams. The stability was evaluated by comparing the results from the dispersion analyser LUMiSizer at various temperatures and current load tests in an oven. The pseudoplastic properties were confirmed by the rheology characterization of the flow properties, which makes the BB cream a continuous layer on the skin after it is spread. In order to protect against sunlight, it was necessary to determine the SPF and measure the colour shades of the prepared BB creams for comparison with commercially available preparations.
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Influence of stirring time on cosmetic stability
Grujić, Ksenija ; Sovová, Šárka (referee) ; Hurčíková, Andrea (advisor)
This bachelor thesis is based on the study of the influence of mixing time and revolutions per minute on the preparation of BB creams. The literature review of the thesis is based on the acquired information about the topic. The basic concepts and problems concerning dispersion systems, emulsions, mixing methods and cosmetics are described in this part of the thesis. The first segment of the experimental part is based on the preparation of BB creams themselves. The influence of agitation time and speed on the stability of prepared samples was tested. The stability of the samples was tested on LUMiSizer. The data were compared and processed.
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Study on the Effect of Biochar Application on Organic Matter in Soil
Kurková, Marie ; Sovová, Šárka (referee) ; Kalina, Michal (advisor)
This bachelor thesis studies the effect of the application of biochar on the composition of organic matter of two different soil samples. Specifically, the total content of organic matter in the soil and the ratio of humic and fulvic acids in these soils before and after the application of biochar were monitored. The composition of the soil mass was also observed thermogravimetrically and by using the certified method of humic and fulvic acids isolation from samples of studied soils. Furthermore, the effect of biochar on the growth of a model plant (maize – Zea mays) was observed. From this point of view, differences in plant growth were possible to observe from the beginning of the experiment, both in comparison with samples with and without biochar and in comparison with samples containing different doses of biochar. The type of soil used for cultivation experiments also influenced on plant growth.
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