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Determination of enantiomers of amino acids by HPLC
Michalčíková, Regina ; Janečková, Lucie (referee) ; Tesařová, Eva (advisor)
This Bachelor's thesis deals with determination of amino acids enantiomers, namely alanine in the experimental part, by high performance liquid chromatography using chiral stationary phases based on teicoplanin. The theoretical part is focused on summarizing the fundamental issue of chirality and chiral amino acids in foods, the characteristics of high-performance liquid chromatography, as one of the most appropriate methods to enantioseparation amino acids, and description of the methods of derivatization, which are used in determination of enantiomers of amino acids. The experimental part deals with the separation of alanine enantiomers, with the choice of the best separation system for the separation and determination of D-and L-alanine in fruit juice.
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Switching of spin vortices in magnetic nanodiscs
Hladík, Lukáš ; Pekárková, Jana (referee) ; Urbánek, Michal (advisor)
The diploma thesis deals with the switching of spin vortices in magnetic nanodisks. First, the basic concepts of (micro)magnetism are defined and existing theoretical and experimental achievements in the field of switching of the two basic characteristics (chirality and polarity) of magnetic vortex are summarized. Then the principle of dynamic switching of magnetic vortex chirality using in-plane magnetic field pulse with a well defined amplitude and duration is presented. There is no need to use a certain shape of nanodisks or asymmetry in magnetic field distribution. Nanostructures were prepared by the multi-step electron beam lithography and ion beam sputtering. Individual steps of sample preparation and optimization for the magnetization dynamics measurements are described. Finally, the experimental measurements of the dynamic switching of chirality on prepared samples obtained by transmission x-ray microscopy at the synchrotron Advanced Light Source at Berkeley, USA are presented and discussed.
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Chiral analysis of drug residuals in waste waters
Svobodová, Dagmar ; Opatřilová, Radka (referee) ; Čáslavský, Josef (advisor)
The theoretical part shortly describes chirality with focus on chiral pharmaceuticals. The processes of their absorption, distribution, metabolism and elimination in human body are discussed. These points are very important to understand possible fate of chiral drugs in the environment as there is only little data concerning their environmental behaviour. The occurrence and enantioselective toxicity of chiral drugs is also discussed here. One of the chapters describes non-steroidal anti-inflammatory drugs, as they are analyzed in the wastewater in the experimental part, and their occurrence in the environment. The experimental part describes optimization of the enantioselective HPLC method using Chiralpak AD as column for ibuprofen and ketoprofen. Reproducible separation of enantiomers wasn’t achieved for naproxen. Optimized methods were then applied for analysis of samples from municipal wastewater treatment plant in Brno-Modřice.
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Chirality and its importance in environmental organic analysis
Svobodová, Dagmar ; Friedl, Zdeněk (referee) ; Čáslavský, Josef (advisor)
This bachelor thesis is elaborated as literature search focused on the characterization of chirality and its importance for the environment. This work also gives review of the analytical methods and procedures aplicable for the chiral analysis of the organic pollutants. Obtained information showed that the importance of the chirality in the environmental chemistry is great. Individual enantiomers exhibit different toxicity and biological activity in the environment and therefore their monitoring by chiral analytical methods is essential.
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