The development of a capillary electrophoresis (CE) method for the determination of inorganic and organo mercury species as their dithizone sulphonate (DzS) complexes using coated capillary columns is described. The complexes were pre-formed before injection and detection was by direct measurement of the visible absorbance of the complexes. Dithizone sulphonate was used in place of cysteine to separate methyl mercury in the final stage of a simplified Westoo extraction procedure. The method was than applied to the analysis of methyl mercury in a crab and several fish meat samples. Good quantitative performance is demonstrated by spiking experiments and analysis of DORM-1 certified reference material. The method was found to be very sensitive and a detection limit of 2 µg Kgˉ¹ could be achieved for a l0g sample of fish flesh. A CE method for the determination of uranium (VI) as the arsenazo III complex was developed and the effect of interfering metal ions was studied. The calibration was found to be linear from 10 µg 1ˉ¹ -10 mg 1ˉ¹ using gravity injections and a detection limit of less than 1 µg 1ˉ¹ was achieved with electrokinetic injection. A study was made of injection techniques and their applicability to the enhancement of sensitivity in synthetic standards and environmental samples. The effect of capillary surface chemistry on the peak shape of the migrating uranyl-arsenazo III was also studied using fused silica capillaries with two different internal coatings and three polymeric capillaries. A study was also carried out on the construction and investigation of a post-capillary reactor for the determination of trace metals by UV-Vis absorption after formation of intensely absorbing coloured complexes. The main principle of operation was based on the infusion of the colorimetric reagent into a small 50µm gap between the separation capillary and the reaction capillary. The gap was enclosed by a permeable membrane and the flow of reagent was achieved by the application of a slight pressure to the post-capillary reactor cell. Two reagents were studied, namely, xylenol orange (XO) and 4 (2-pyridylazo) resorcinol (PAR), for the separation and detection of copper (U), cadmium (II), cobalt (II), nickel (II), zinc (II), and manganese (II). Lead (II) was also included in the XO system.

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Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Lucia Hanuščinová Supervisor: Assoc. Prof. Přemysl Mladěnka, PharmDr., PhD. Title of diploma thesis: Ability of copper chelators to interact with iron and zinc Copper plays in the human organism a role of an element with indispensable significance, whose biological influence and effects depend on its quantity. With elevated concentrations in the human body, copper becomes toxic, resulting in pathological conditions. The most well-known diseases is the Wilson's disease, whose treatment consists of oral administration of chelators, i.e. chemical compounds, which are capable of binding copper ions in various proportions and eliminating them from the organism. Chelation therapy is currently the first choice after confirmation of the diagnosis. Chelation toxicity results from several factors, e.g. inhibition of copper dependent enzymes or low selectivity to metals. And precisely the selectivity of chelators is being discussed in this diploma thesis. An ideal chelator should not interact with any of the other physiological ions, that are necessary for the proper functioning of the organism. Five of the most frequently therapeutically or experimentally used substances /trientine, D-penicillamine,...