The work is focused on the determination of heavy metals - lead and cadmium in smoked fish products which were bought from stores in the Czech Republic during 2014. These were samples of smoked tuna and marlin (Principesca) in which the above limit values of mercury had been found in a previous study within the SVOČ SPŠCH Brno and a bachelor thesis MENDELU (Ventrubová, 2015) . The theoretical part involves the issue of heavy metals (lead and cadmium), their forms as well as their entry into the environment and accumulation in fish organisms. The experimental part is devoted to the determination of lead and cadmium concentrations in the samples, evaluation and comparison of the results with the relevant hygienic limits. Lead concentrations in the samples did not exceed the allowed hygienic limit, however, cadmium concentrations exceeded the allowed hygienic limit in all samples and this was confirmed by SZPI.

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Sepsis is a worldwide health condition. It is caused by disproportionatly large immunity system response for patogene presence. Fast and accurate diagnosis of sepsis can make difference between life and death. For clinical diagnosis of sepsis is used serum protein procalcitonin (PCT) as biomarker. Procalcitonin concentration level in patient bloodstream increases up to thousand times in short time period. Severity of sepsis can be determined by correlation with its concentration in bloodstream. To determine PCT level in patient bloodstream a broad variety of specialized instrument is used. All methods have same principle of measurement - PCT-antibody interaction. Procalcitonin level is then quantified by calibration curve method. During these measurements non-specific protein-antibody interactions can occur and distort the quantification of PCT level. Mass spectrometry due to its properties comes into consideration as an alternative method, that can be used for PCT determination. Aim of this diploma thesis was in situ enrichment of PCT on surface modified affinity carriers with immobilized antibody against PCT. These carriers are compatible with matrix assisted laser desorption/ionization time of flight mass spectrometry. Mass spectrometry provides mass spectrum, where PCT and other signals...

Stem constitutes approximately from 3 to 5 percent of total weight of a grape. The chemical structure of stem is mainly related to a variety, habitat conditions and ripeness. Stem consists from 35 to 90 percent of water, it also consists of sugar, tartaric acid and malic acid, tannins and vegetable dyes. In the production proccess of making wine, stem is perceived only as a residual part and there is a fact often omitted that stem is not only an integral part of grapes but it is also an indicator to the presence of a disease on the Vitis vinifera. Although stems have a drainage effect, they are improper for the production of wine itself, because the green stems in the stum cause the objectionable taste of grass. The first part of the thesis contains the general informations about stem: its composition, detailed description of the most contained substances and possibilities of the use of stem as well. My thesis also contains of detailed descripted spectrometric and chromatografic analysis and results as a part of the conducted research on substances contained in stem. In the last part of the thesis there are proccesed facts using the search method. They are mainly derived from foreign literature and are divided to several chapters: comparison of the derived results with international studies, new technologies that evaluate the substances contained in stem and also the effects of stem on human health.

The thesis deals with determination of selected nutrients (copper, zinc, iron) in nuts. In total, 33 samples, bought in retail chains in Czech Republic, were analysed. The theoretical part of the thesis is focused on characterisation of individual nuts including other fruits, which are consumed as nuts. In the practical part, contents of copper, zinc and iron were measured by the atomic absorption spektrometry method. From the results, it is clear that the highest amount of copper was found in Brazil nuts. The lowest amount of copper was found in macadam nuts. Overall the highest content of zinc within all types of nuts was found in pine nuts and the lowest amount of zinc was determined in coconut and edible chestnuts. Iron was the most contained in alaburks, cashews and pine nuts. The lowest quantitty of this element was measured in edible chestnuts.

This diploma thesis is focused on an analysis of mercury content in eatable mushrooms. Theoretical part describes transmission of mercury from environment to the soil, next to the mushrooms. Practical part was focused on the determination of total mercury content. Determination of mercury content was provided by atomic absorption spectrometer AMA 254. The samples were obtained from forests in the Czech Republic and Slovakia in 2017 and 2018 and from supermarkets in the Czech Republic. This thesis compares mercury concentration among various types of mushrooms obtained from various collection sites. Moreover, the contents were compared within different collection years, country of origin or size of mushroom. Furthermore, average mercury contents in mushrooms obtained from forests and supermarkets were compared. The highest concentration was found in wild-grown Agaricus bisporus and Macrolepiota procera, which have been grown in areas with higher mercury presence. The highest hazard index was calculated in this samples, too. The highest bioconcentration factor was calculated in Boletus reticulatus.

The aim of this master's thesis was to determine the contents of cadmium, lead and mercury in sea fish. Fresh and frozen fish from 17 FAO localities were bought in Czech markets. The theoretical part of this work describes the determined heavy metals and their relation to the environment. All 30 analyzed fish species are also described here. Atomic absorption spectrometry technique was used for determination of cadmium, lead and mercury concentration in the practical part of the work. Twelve samples exceeded the maximum levels for mercury (0.5 mg/kg or 1 mg/kg for selected fish species) and three fish samples exceeded the maximum level for cadmium (0.05 mg/kg) set by Commission Regulation (EU) No 1881/2006, as amended. The maximum level of lead concentration (0.3 mg/kg) was not exceeded in any fish sample. Results of this work show, that samples of marlin (Tetrapturus albidus) and swordfish (Xiphias gladius) are one of the most contaminated fish which can pose a great risk for human health after regular consumption. Because mercury and cadmium contents in some samples were higher than maximum levels recommended by World health organization WHO and Czech legislation, our research initiated an investigation of CAFIA, which led to withdraw some batches of the fish from the Czech markets.

One of new techniques in the field of analytical chemistry, which has more and more practical use, is mass spectrometry imaging. With its ability to record representation of substances in samples during the tissue analyze arise problem with a lot of output data which needs to be handled programmatically. The goal of this work is to create an software for processing and visualization data of new standard imzML. As a part of the work, the field of mass spectrometry, primarily MALDI TOF mass spectrometry, is briefly introduced. There are also introduced some methods for mass spectrometry data preprocessing. The work also contains a summary of current state of available software for processing and visualization of mass spectrometry data. With requests from cooperating laboratory a novel software is designed and implemented, which besides the visualization itself, can preprocess the data for example data smoothing with Savitzky-Golay method, internal calibration or peak detection with continuous wavelet transformation. The software was successfully tested on real data sets.