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Study of the interaction of selected pharmaceuticals with microplastics
Ioani, Aldina ; Řezáčová, Veronika (referee) ; Doležalová Weissmannová, Helena (advisor)
The bachelor thesis aims to study the interaction of selected pharmaceuticals from the group of analgesics and antibiotics with microplastics. The analysis was conducted in the mid-infrared region, which is used to identify chemical structure of the substances. Fourier transform infrared spectroscopy was used as an analytical method. The samples were subjected to technique attenuated total reflection. Ibuprofen and trimethoprim were chosen as analytes due to their common usage in the population. Sorption of pharmaceuticals was undergoing on polyhydroxybutyrate, which is a kind of biodegradable plastics and polyethene terephthalate, which is synthetic. Measured results showed that for the study of interaction with pharmaceuticals, it is more suitable to use biodegradable plastic polyhydroxybutyrate than polyethene terephthalate because of its better results. Infrared spectra output is very influenced by a selection of a solvent.
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Use of liquid chromatography to analyze caffeine solutions exposed to plasma
Brabcová, Kristýna ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This thesis deals with the current problem of increasing concentration of caffeine in water that is connected with caffeine consumption among people. This problem is not that urgent becusase the concentration is not high and for human is not so harmful. The bigger populaton is, the more caffeine people consume and the amount of caffeine in wastewater rises. This fact could be considered as a future problem. An appropriate method effective for elimination of harmful substances are advanced oxidation processes (AOP). Theoretical part describes purine alkaloids with detail desctription of caffeine. Plasma was chosen as a method for caffeine degradation and there are some facts described. There is a chapter about appropriate analytical methods. The samples were picked after periodical time intervals. These samples were analyzed by UHPLC. The results were compared with study dealing with this theme.
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Determination of volatile substances of natural extracts intended for cosmetic application
Paskevych, Olha ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
Tato bakalářská práce je soustředěná na zkoumaní přírodních komerčně dostupných extraktů, které se používají do přírodní kosmetiky. Literární rešerše byla zaměřena na téma obsahu těkavých látek v přírodních extraktech používaných v kosmetice, jejich charakterizace a možnosti stanovení, problematika výskytu alergenů v přírodní kosmetice. Na základě tohoto přehledu byla navržena optimální metoda pro analýzu vzorků přírodních extraktů s přihlédnutím k dostupné analytické instrumentaci. Následující výtažky byly studovány se zaměřením na kvalitativní stanovení: mandle, aloe vera, hřebíček, Etiopská káva, zázvor, cibule.
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Risks associated with the use of biochar in the terrestrial ecosystem
Valeeva, Adeliia ; Řezáčová, Veronika (referee) ; Zlámalová Gargošová, Helena (advisor)
The aim of this bachelor thesis was to assess the ecotoxicity of biochar produced from sewage sludge in Ingolstadt. Biochar is one of the carbon storage options and it’s applied to the soil. Biochar has an effect not only on the terrestrial ecosystem in direct contact of organisms with the sample, but also on aquatic in the leaching of substances from biochar into water. Therefore, contact and aquatic tests were chosen to assess the ecotoxicological effect. The representative of the decomposers was the earthworm Eisenia fetida, the primary producer – the plant Lactuca Sativa and the Daphnia magna was chosen from the aquatic organisms. The test results differed slightly, but the lowest negative effect on the test organisms was shown by soil samples with the addition of 5 g/kg and 10 g/kg granular biochar.
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Platinum group elements in waste and surface waters
Novotný, Matěj ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This assignment provides a detailed description of platinum metals, their occurrence in surface and waste water and their determination options. Currently, platinum metals are widely used in the automotive industry as a part of a catalyst, as well as in medicine and jewelery. Release of these metals in pure form and the form of oxides leads to their subsequent accumulation, which directly affects fauna and flora. Due to that, the living conditions and health status of some organisms are petting worse.
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Identification of contamination sources in the PET recycling
Snopková, Martina ; Řezáčová, Veronika (referee) ; Kučerík, Jiří (advisor)
This paper deals with the identification of plastic contaminants in polyethylene terephthalate (PET) flakes obtained by mechanical recycling of PET bottles. The presence of contaminants in recycled material is undesirable and it is necessary to implement and optimize technologies to separate them. For improving the effectiveness of separation, it is crucial to determine the material of the contaminant. Papers that are focusing on the contaminant analysis in PET flakes are sporadic. In practice, there are not enough sources for enhancing the effectiveness of separation based on the material of the contaminant. The goal of this thesis is to provide missing information about the materials of plastic impurities. Obtained findings will contribute to efficiency improvement of contaminant separation and production of better-quality recycled material. For contaminant analysis, Fourier-transform infrared spectroscopy with attenuated total reflection technique (FTIR-ATR) was used. The samples were analyzed using an ALPHA II device with an ALPHA-P module with the diamond crystal. It was found out that the most frequented contaminants are polymers polystyrene (PS) and its modifications, polyethylene terephthalate glycol (PETG), PET mixed with other polymers or additives, polypropylene (PP), polyamide (PA), styrene acrylonitrile (SAN) and polyvinylchloride (PVC). Based on these results, the recommendations for enhancing the efficiency of separation were developed. Some of the results pointed out the actual problems that complicate PET bottle recycling.
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Study of sorption properties of biochar
Kocinger, Oskar ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This diploma thesis deals with sorption properties of biochar produced from wood biomass treated with concentrated hydrochloric acid and activated carbon with respect to the triazine pesticide propazine. Although pesticides are widely used in both agriculture and the private sector worldwide, they pose a significant risk to ecosystems and human health. Propazine belongs to the group of chlorinated triazine herbicides, which pose a risk mainly as endocrine disruptors. The sorption of organic pollutants using pyrogenic carbonaceous materials promises an efficient and economically affordable solution, which has recently received increasing attention from the scientific community. In this work, we used isotherms to describe the equilibria of propazine sorption to given sorbents during vial experiments. Analysis of the propazine content in the model water solutions after reaching equilibrium was performed using high-performance liquid chromatography with mass detection.
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The occurence of Cadmium in environment
Bělohlávková Staffová, Petra ; Řezáčová, Veronika (referee) ; Sommer, Lumír (advisor)
Heavy metals, including cadmium, belong to the contaminants of the environment. With permanently increasing pollution, there is an increase of these metals in the water, in the air and in the soil, which are involved in the food chain and subsequently the food of human. Cadmium has received considerable attention for its toxicological properties. Similarly, monitoring of cadmium in the Czech Republic is relatively large. There is a legislative measure regarding not only the permitted level of cadmium in the air, in the water, in the soil, but also food and is also restricted its use in the industry. Further they developed methods of its determination. In this work was devoted to attention photometric determination and some electroanalytical methods, then spectrometric methods mainly atomic absorption spectrometry and atomic emission spectrometry, which is currently the most widely used.
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Influence of different forms of titanium dioxide nanoparticles on soil organic matter properties
Miklasová, Marta ; Řezáčová, Veronika (referee) ; Kučerík, Jiří (advisor)
Nanoparticles present potential risk for environmental compartments including soil. Previous works have been focused on negative effects of nanoparticles on soil biota, however studies about the influence of nanoparticles on soil properties are still limited. This thesis investigates an impact of 20 nm titanium dioxide nanoparticles on selected water properties in soil organic matter exposed to air with various relative humidity. Indeed, at 43, 70 and 95 % dominate different water types, i.e. water adsorbed on soil organic matter, water in water molecular bridges and phase water, respectively. Differential scanning calorimetry (DSC) was used in the study. An important finding is that nanoparticles reduce the stability of water molecular bridges under 70% relative air humidity and generally reduce evaporation enthalpy of water, which represents the ability of the soil to retain water. In the next part the influence of nanoparticles on total water in soil was observed. Under low relative humidity, rutile and anatase affected soil in different ways due to their various hydrophilicity. Under higher relative humidity this effect disappeared. In the last part, ice melting and water evaporation enthalpies of nanoparticle solutions were measured to confirm the presumed effect of nanoparticles on water. The ice melting enthalpy of the solutions was higher relatively to pure water, while the evaporation enthalpy showed a reverse trend (decrease). This confirmed the effects of nanoparticles both for pure water and soil water.
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Zinc in food suplements
Sauchanka, Katsiaryna ; Suková, Petra (referee) ; Řezáčová, Veronika (advisor)
The aim of this bachelor thesis was to determine zinc in the dietary supplements by the voltammetric method. The general properties of zinc, its occurrence, toxicity and influence on human health are described in the first part. Next the methods, including a detailed description of the voltammetric analysis, are summarized. The experimental part is focused on the process of optimization of the conditions for zinc voltammetric analysis and the application of the optimised method on real samples.
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