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Influence of content of organic matter and calcium on immobilization of pharmaceuticals in soil
Kotradyová, Viktória ; Sedláček, Petr (referee) ; Klučáková, Martina (advisor)
This thesis aimed to highlight the problem of antibiotics and their presence in nature, particularly tetracycline. High global consumption, limited metabolism in the body and incomplete degradation in wastewater treatment plants represent the reasons why pharmaceuticals have been found in the environment. Their presence might have a negative impact on the natural ecosystem, including humans. Therefore, addressing their behaviour and finding solutions for their removal from nature seems important. The soil itself has a self-cleaning capacity, which may immobilise these pollutants into organic structures to prevent their subsequent migration. The presence of inorganic cations in soil plays an essential role in the sorption process of antibiotics. Calcium ions from the soil with whom the tetracycline forms chelate complexes, should be also taken into account. Regarding the practical part, tetracycline interactions with soil systems were studied in both sorption and desorption experiments. Four soils with different amounts of organic matter and calcium have been examined. Tetracycline was extensively adsorbed to all four soils. Desorption processes showed low efficiency and refer to stable adsorption onto soil. The experimental data were fitted by Freundlich and Langmuir isotherms, where the second mentioned is suitable for three of the four soils. Subsequently, sorption and desorption experiments were conducted in four different pH buffers (3, 5, 7 and 10). The effect of pH on sorption was not significant, however during desorption at lower pH higher desorbed levels of tetracycline were observed. Photodegradation of tetracycline in solution was investigated to determine the rate of degradation of tetracycline on light, where the results indicated that the concentration decreased by 22 % after 29 days compared to the applied concentration. Quantitative analysis was carried out using UV-VIS spectroscopy and liquid chromatography. In addition, the soil spectra of the FTIR were measured to obtain information on the sorption mechanism
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Migration of pharmaceuticals in soil systems
Janebová, Denisa ; Pekař, Miloslav (referee) ; Klučáková, Martina (advisor)
The increasing use of drugs leads to their frequent occurrence in the environment, which poses a risk not only because it can lead to the proliferation of antibiotic-resistant bacterial strains, but also because it can threaten human health. Therefore, this work focuses on the issue of the occurrence and behaviour of two antibiotics in soil, specifically tetracycline and sulfamethoxazole. Due to the presence of soil organic matter, it is believed that the soil can partially prevent the spread of drugs that enter the environment. The diploma thesis involved conducting diffusion experiments in soil columns under real conditions to determine the effective diffusion coefficients of tetracycline and sulfamethoxazole in three extraction agents. Sorption and desorption processes were also conducted in the individual layers of the soil column. The concentrations of the leachates were measured using UVVis spectrometry and liquid chromatography, while FTIR spectrometry was used to confirm the presence of the bound drug in the soil column.
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Interactions of pharmaceuticals with humic substances in model hydrogels
Fleischhackerová, Claudia ; Krouská, Jitka (referee) ; Klučáková, Martina (advisor)
This bachelor's thesis is focused on the study of drug diffusion in humic acid hydrogels. The instantaneous surface source diffusion method was used for this study. This method was based on the observation of emerging diffusion profiles of drugs which diffused in the humic gel at certain time intervals. Then, this method was used to determine the diffusion coefficients of the drugs used in the gels. The main aim of the experimental part was to study the influence of the interaction of drugs with humic acids that diffused through the humic gel. Two drugs were used as a diffusing medium, i.e. ibuprofen and tetracycline. They are pharmaceuticals, the consumption has been increasing in humans and animals in recent years, that's why they are often detected in the environment. The concentration profile of these drugs in humic acid hydrogels was determined by UV–VIS spectrometry.
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Development of a method for determination of antibiotics in milk using high performance liquid chromatography
Juglová, Zuzana ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This diploma thesis focuses on optimization and validation of the method for a mixture of tetracycline antibiotics (oxytetracycline, tetracycline) determination using high performance liquid chromatography with a diode array detector (HPLC–DAD). The aim of this thesis was to determine suitability of the system for the determination of these antibiotics in milk. The theoretical part is focused on individual groups of antibiotics and their mechanism of action, resistances and possibilities of use. Next point of this thesis is legislation, which describes permitted amounts of antibiotics in milk. In this study, the HPLC method and validation parameter is described in detail. The experimental part deals with creation and optimization of the method and its validation. Following validation parameters were verified: system suitability, linearity, method accuracy, limit of detection and quantification, robustness. The results obtained indicate mostly suitable ratio of mobile phase of 0,01 M trifluoracetic acid:methanol:acetonitrile = 80:10:10. The wavelength 355 nm was found as the most feasible for this method after evaluating the result. Determination of robustness showed that the method is robust, and the only significant effect on the robustness was observed in column changes.
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Interactions of pharmaceuticals with humic substances in model hydrogels
Fleischhackerová, Claudia ; Krouská, Jitka (referee) ; Klučáková, Martina (advisor)
This bachelor's thesis is focused on the study of drug diffusion in humic acid hydrogels. The instantaneous surface source diffusion method was used for this study. This method was based on the observation of emerging diffusion profiles of drugs which diffused in the humic gel at certain time intervals. Then, this method was used to determine the diffusion coefficients of the drugs used in the gels. The main aim of the experimental part was to study the influence of the interaction of drugs with humic acids that diffused through the humic gel. Two drugs were used as a diffusing medium, i.e. ibuprofen and tetracycline. They are pharmaceuticals, the consumption has been increasing in humans and animals in recent years, that's why they are often detected in the environment. The concentration profile of these drugs in humic acid hydrogels was determined by UV–VIS spectrometry.
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Development of a method for determination of antibiotics in milk using high performance liquid chromatography
Juglová, Zuzana ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This diploma thesis focuses on optimization and validation of the method for a mixture of tetracycline antibiotics (oxytetracycline, tetracycline) determination using high performance liquid chromatography with a diode array detector (HPLC–DAD). The aim of this thesis was to determine suitability of the system for the determination of these antibiotics in milk. The theoretical part is focused on individual groups of antibiotics and their mechanism of action, resistances and possibilities of use. Next point of this thesis is legislation, which describes permitted amounts of antibiotics in milk. In this study, the HPLC method and validation parameter is described in detail. The experimental part deals with creation and optimization of the method and its validation. Following validation parameters were verified: system suitability, linearity, method accuracy, limit of detection and quantification, robustness. The results obtained indicate mostly suitable ratio of mobile phase of 0,01 M trifluoracetic acid:methanol:acetonitrile = 80:10:10. The wavelength 355 nm was found as the most feasible for this method after evaluating the result. Determination of robustness showed that the method is robust, and the only significant effect on the robustness was observed in column changes.
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