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Analysis of substances released from composite dental material
Fučík, Jan ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This master's thesis deals with a present problem of alternative dental fillings, which should replace amalgam fillings. Although there are health concerns about these alternative materials, especially resin composite fillings raise concerns, because they release potentionally harmful substances into the oral cavity. Accordingly even this medical device subjects various tests before releasing to the commercial market and one of these tests was carried out according to ČSN EN ISO 10993 and available scientific literature in the experimental part of this thesis. The amalgam controversy, substances used for manufacturing of resin dental fillings and analytical methods are described in the theoretical part of the thesis. In the experimental part of the thesis, 30 days long cumulative extraction experiments were carried out into various extraction mediums in order to assess suitability of new dental resin filling from ADM, a.s. by comparison with commercially available dental material from company GC EUROPE N.V. These samples were analysed by LC-MS and the amount of eluted substances from dental composites to extraction medium was quantified.
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Study of the occurrence of colistin in soil
Veldamonová, Aneta ; Zlámalová Gargošová, Helena (referee) ; Mravcová, Ludmila (advisor)
Colistin is a polypeptide antibiotic used as a "last resort" effective against Gram-negative bacteria. However, increase in its consumption in veterinary medicine in the last 30 years has led to the development of bacterial resistance even to colistin. The application of slurry to soil containing unmetabolized colistin and resistant bacteria poses a risk, because the resistance of bacteria to colistin can be further developed and spread to other components of the environment. Therefore, this work was focused on the creation and optimization of extraction and analytical methods for soil samples containing colistin. Colistin was detected by liquid chromatography in connection with mass spectrometry (HPLC/MS and UPLC/MS/MS). Many extraction solutions have been tested in connection with ultrasonic extraction and purification on various SPE columns, yet colistin has not been successfully extracted from the soil. Colistin was successfully detected only in the slurry extract. The reason why colistin was not detected in soil extracts could be the sorption of colistin on soil organic matter or the formation of complexes of colistin with humic substances.
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Analysis of fluoroquinolone antibiotics in the soil
Vdolečková, Monika ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
The thesis dealt with the global problem of the occurrence of pharmaceuticals in the environment, specifically fluoroquinol antibiotics (ciprofloxacin and enrofloxacin), which are among other critically important antibiotics. These drugs enter the soil environment through the application of already contaminated animal waste (e.g. manure) or through wastewater used in irrigation or through the application of treated sewage sludge, which may contain drug residues. Increasing concentrations of these antimicrobial drugs in the environment provide an environment for the emergence and spread of microbial resistance. The accumulation of these drugs then leads to the emergence of resistance to these antibiotics. The experimental part of the thesis focused on the optimization of a method for the extraction and subsequent determination of fluoroquinolones in soil and litter. For this purpose, parameters related to the extraction yield of fluoroquinolones from the soil matrix were optimized, such as sample weighting, selection of a suitable extraction medium, SPE performance, elution method from the SPE, etc. Extraction recoveries of 70 to 140 % were achieved as part of the optimization. Finally, the optimised method for extraction of fluoroquinolones from poultry litter and soil samples provided by the ÚKZÚZ was used. The experimental results confirm the long-term persistence of these drugs in the environment.
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Optimization of the coagulation procedure for wastewater treatment
Švábová, Martina ; Mravcová, Ludmila (referee) ; Repková, Martina (advisor)
This bachelor thesis deals with the optimization of the determination of the chemical oxygen demand in the test tubes and the optimization of the coagulation process for the external company. COD is one of the basic analysis for all types of water, although there are numerous environmentally-unfriendly agents in case of using a standard version produced. Therefore, an alternative method of using the test tubes was used, the procedure of which has been modified from ČSN ISO 15705 and is now available to the public. The aim was also to optimize the coagulation process in the treatment of wastewater from an industrial paintshop. The minimum dose of coagulating agent occurring in the instructions for usage was disproved and the pH value at which aluminium sulfate as a coagulating agent was proposed.
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Determination of hyaluronan by electromigration methods
Bártová, Adéla ; Mravcová, Ludmila (referee) ; Řezáčová, Veronika (advisor)
This thesis is focused on description hyaluronic acid, characterization of its behaviour in water solutions, its chemical-physical properties and its using in different industrial sectors. The next part deals with possibilities of its analysis. The following section of the thesis is focused on electromigration techniques with special attention dedicated to capillary electrophoretic methods, especially capillary zone electrophoresis. The aim of this thesis is optimization of the method of determination of hyaluronic acid in water solutions by capillary zone electrophoresis.
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Determination of nonylphenol and its isomers in waters
Sedláček, Jaroslav ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
This diploma thesis is focused on the issue of nonylphenol, degradation product of surfactants. Nonylphenol however most often arises in wastewater treatment plants predominantly during the microbial degradation of nonylphenol ethoxylates used in industry. It is a substance highly bioaccumulative, toxic predominantly to aquatic organisms. Furthermore, it belongs among hormone disruptors. The detailed research was prepared, on the basis which experimental part of diploma thesis was solved. Nonylphenol was determined in samples of the wastewater. The solid phase extraction (SPE) was used for the isolation of the analyte and purification of the extract. The final determination was performed on the gas chromatography with tandem mass spectrometry with time of flight analyzer (TOF). All steps of the preanalytical and the analytical procedure were optimized.
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Removal efficiency of selected drugs by various sorptive materials from water
Štofko, Jakub ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
This thesis deals with sorption of selected drugs from model water by various sorption materials. Contamination of water resources by the pharmaceutical industry is a major problem today. Wastewater treatment plants, whose technological processes are unable to completely remove them, have a significant share in the penetration of these substances into the environment. At present, attention is paid to alternative materials that are capable of eliminating these substances. One of the potential sorption materials is biochar as one of the main pyrolysis products. This work focused on the assessment of the sorption properties of the different types of biochar and commercially used active charcoal. The sorption properties of the individual materials were compared with respect to the non-steroidal anti-inflammatory substance ibuprofen and the sulphonamide antibiotic sulfamethoxazole. The results of vial experiments were analysed on a liquid chromatograph with mass detection.
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Determination of PLA microplastics in soil by using pyrolysis methods
Románeková, Ivana ; Mravcová, Ludmila (referee) ; Kučerík, Jiří (advisor)
Nowadays, plastic waste poses one of the greatest risks to the environment. Plastics affect the environment at all stages of their life cycle. Bioplastics have become widely used as a substitute for conventional plastics, without detailed examination of their behavior in real environmental conditions. As a result, it is assumed that they can accumulate in the environment and the question arose as to how to identify them. The main goal of this thesis is to develop a method based on sample pyrolysis that is suitable for the identification and determination of the amount of PLA microplastics in soil and other solid matrices. Three types of soils and sludge were used for analysis. These matrices were spiked to obtain concentration ranges 0,2% - 5,0%. The pyrolysis resulted in evolution of gases with the signals m/z 29, 43 and 44, witch originated from PLA and are suitable for qualitative and quantitative analysis. Analysis of PLA in sludge was more complicated due to similarity of gases evolved from pure matrices. We tested three approaches based on analysis of signal´s peak areas, intensities and temperatures of gas evolution. While the first approach failed, the last two approaches appeared to be promising for qualitative and quantitative analysis of PLA in the sludge. Several methods suitable for qualitative and quantitative analysis of even very small amounts of PLA in soils and sludge have also been designed/developed. These methods were based on analysis of the composition and dynamics of the released gases and the characterisctic degradation temperatures.
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The study of metallocene anticancer therapeutics-cells interaction
Bilavčíková, Kristýna ; Mravcová, Ludmila (referee) ; Vašinová Galiová, Michaela (advisor)
There were almost 600 thousand patients in Czech Republic until 2017 and the number keeps rising. Chemotherapeutics used today have lots of undesirable side effects, so scientists around the world are trying hard to find more specific and less cytotoxic drugs. In this bachelor’s thesis, potential drugs based on metallocene with a central atom of Ru, Hf or Zr were studied, always in three different drugs for each element. The permeability and distribution of these drugs into lung cancer cell lines were investigated. These drugs were detected by analysis of solutions and laser ablation with an ICP mass spectrometer. Based on the experiment, the greatest potential was found for the ruthenium-based drug 133, which had the highest permeability and was able to get into the cells in the highest volume.
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Determination of organic compounds in biochar produced by microwave torrefaction of biomass
Meindl, Jiří ; Vávrová, Milada (referee) ; Mravcová, Ludmila (advisor)
The thesis is focused on a determination of polycyclic aromatic hydrocarbons (PAHs) contained in dried pelletized sewage sludge and pelletized biochar. Biochars were made in mild conditions by microwave torrefaction of prepared sewage sludge. There were analyzed and quantified the 34 of standardized PAHs compounds in two series. The first serie, also called “Sada 1”, has been aimed at comparison of extraction methods for the chosen sample of sewage sludge and the sample of biochar. In serie “Sada 1”, there were compared efficiencies of chosen type of solvent or solvent mixture by comparison of yields for 34 standardized analytes in a sample of biochar and a sample of sewage sludge. There were compared also to total yields of PAHs and to number of quantified compounds in analyzed samples. The most reliable extraction method has been used for the next analyses of samples in the second serie called “Sada 2”. In Sada 2, there were compared different samples of the same type (e.g. biochar, sludge). The origin of sewage sludge (small or big sewage treatment plant expressed as PE) and used additives (cellulose, chaff, hay) as modificators for torrefaction process were variables for different type of sample. The results of analysis were identification of the most suitable sewage sludge and additive to be used as modificator for microwave torrefaction process. The main goal of correctly chosen sludge and additive was to minimize production of PAH’s during torrefaction and in samples of biochar.
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