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Modification of electrochemical sensors working electrodes for biological substances detection
Weiss, Vojtěch ; Prášek, Jan (referee) ; Majzlíková, Petra (advisor)
The aim of this work is modification of working electrode surface of screen-printed electrochemical sensors using carbon nanotubes. General knowledge about sensors, their categorization, thick-film technology, properties, preparation and utilization of carbon nanotubes and selected electrochemical methods are reported in theoretical part. Three different methods of working electrodes modification with carbon nanotubes are described in the experimental part of the thesis. Furthermore characterization of modified and unmodified electrodes using cyclic voltammetry, electrochemical impedance spectroscopy and scanning electron microscopy is presented. All results are summarized and discussed in the conclusion of this work.
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Mercury Film Screen-Printed Electrodes
Josypčuk, Bohdan ; Šestáková, Ivana ; Tvorynska, Sofiia
Mercury film screen-printed electrodes (MF-SPEs) were designed, prepared and tested for the first time as perspective representatives among SPEs that allow measuring at high negative potentials. For this purpose, the precise electrochemical (coulometric) preparation procedure for mercury deposition at the working electrode surface of the commercial silver-SPE was developed and a universal method of preparing MF-electrodes from different metal-SPEs was described. An optimal electrolyzer construction for the mercury deposition, electrolyte composition, electrolysis potential, and an activation of electrode surfaces were proposed. Determination of the zinc content in food supplement tablets was used for the MF-SPEs practical testing.
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Preparation, Testing and Application of Amalgam Screen-Printed Electrodes
Josypčuk, Bohdan ; Langmaier, Jan ; Tvorynska, Sofiia
Silver amalgam screen-printed electrodes (AgA-SPEs) were designed, prepared, and tested for\nthe first time as perspective representatives among SPEs for measuring at high negative\npotentials. The precise coulometric preparation procedure for mercury deposition at the\nworking electrode surface of the commercial silver-SPE was developed. An optimal\nelectrolyzer construction for the mercury deposition, electrolyte composition, and electrolysis\nconditions were proposed. The maximum value of hydrogen overvoltage (-1979 ± 4 mV) was\nfound on AgA-SPE with 50% (w/w) of Hg content in 0.1 mol L-1 NaOH, which is more negative\nthan with the original silver-SPE for 387 mV (-1592 ± 12 mV).
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Modification of electrochemical sensors working electrodes for biological substances detection
Weiss, Vojtěch ; Prášek, Jan (referee) ; Majzlíková, Petra (advisor)
The aim of this work is modification of working electrode surface of screen-printed electrochemical sensors using carbon nanotubes. General knowledge about sensors, their categorization, thick-film technology, properties, preparation and utilization of carbon nanotubes and selected electrochemical methods are reported in theoretical part. Three different methods of working electrodes modification with carbon nanotubes are described in the experimental part of the thesis. Furthermore characterization of modified and unmodified electrodes using cyclic voltammetry, electrochemical impedance spectroscopy and scanning electron microscopy is presented. All results are summarized and discussed in the conclusion of this work.
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