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Biomarker detection using electrochemical method with microfluidic chip
Klepáčová, Ivana ; Svoboda, Ondřej (referee) ; Neužil, Pavel (advisor)
The thesis is focused on the development of the electrochemical system with microfluidic platform for the detection of multiple biomarkers. It analyses the use of biomarkers for the early diagnosis of cancer. The theoretical part contains basic information about voltammetric methods and microfluidic systems. The practical part provides solutions to the microfluidic chips, including the description of the used materials, designs, methodologies of preparation and conclusions from the testing of the manufactured microfluidic systems. The thesis describes the lock-in electrochemical system which measures the response of 4 electrochemical cells simultaneously. For the electrochemical system measurements, an electrochemical chip consisting of 64 electrochemical cells was used. The results of the analysis include the processing of the system tests and detected voltammetric curves of the Fe2+/Fe3+ solution and cysteine.
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Thick-film sensors for heavy metals detection
Gajdoš, Libor ; Majzlíková, Petra (referee) ; Prášek, Jan (advisor)
This project describes the possibilities of heavy metals detections in solutions using differential pulse voltammetry with tree-electrode electrochemical thick-film sensors. In the theoretical part, the thick-film technology is described as well as thick-film pastes’ types and compositions, followed by introduction to electrochemistry and electro-analytical methods of measurement. This project also describes the three measured heavy metals – cadmium, lead and copper. In the practical part, heavy metals’ ions detection in solutions using carbon working electrode and determination of the detection limit and sensitivity are described and discussed. Finally the evaluation of obtained results and results comparison to hygienic limits are included.
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Thick-film sensors for heavy metals detection
Polický, Jiří ; Adámek, Martin (referee) ; Prášek, Jan (advisor)
This work covers an area of heavy metals detection using thick-film sensors. Fabrication of screen-printed thick-film sensor and electrochemical analytical methods for detection of chemical elements in aqueous solutions are described in this work. Several commercial and own prepared thick-film pastes were used for carbon based working electrodes. The electrochemical properties of the pastes were examined by cadmium ions detection in potassium chloride solution using differential pulse voltammetry. The best results were achieved on the electrode made of direct grown carbon nanotubes on the electrode layer NM22. A detection limit 20×10-6 mol l-1.was reached with this working electrode material during oxidation process.
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Difference pulse voltametry for detection of metallothionein
Postránecká, Tereza ; Prášek, Jan (referee) ; Provazník, Ivo (advisor)
Metallothionein (MT) is a protein with a characteristic amino acid composition which thanks to its thiol groups can bind metal ions and be involved in the homeostasis of these ions in organism. The protein has its significance in carcinogenesis, could be a suitable marker for certain types of tumors. MT has many specific functions in organisms. It can be studied using several techniques. In common use electroanalysis is used as method for determining the concentration of MT. More specifically, this work is focused on differential pulse voltammetry using Brdička reaction.
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Electrochemical impedance spectroscopy as a nanostructured bioelectrodes characterization method
Vrbová, Eva ; Urbánková, Kateřina (referee) ; Hrdý, Radim (advisor)
Diploma thesis deals of nanostructured surfaces, nanoparticles and electrochemical characterization methods such as cyclic voltammetry, differential pulse voltammetry and electrochemical impedance spectroscopy. The aim of this thesis is a theoretical research issues of production and characterization nanostructured modified electrodes. The practical part is the production of biomodified nanostructured electrodes by anodi- zation W/Al layers with galvanic deposition of gold or deposition of mercury, a modifi- cation of the electrodes by 11-mercaptoundecanoic acid and by bovine serum albumin (BSA). The thesis includes SEM images of nanostructured electrodes contact angle mea- surements of these electrodes and form an electrical circuit with subsequent simulation waveforms.
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Influence of liposomal platinum cytostatics on cancer cells – voltammetric study
Laníková, Petra ; Prášek, Jan (referee) ; Hynek, David (advisor)
Aim of this thesis is voltammetric study influence of liposomal platinum cytostatics on cancer cells. One of the goals is summarize available informations about influence of cisplatine on cancer cells, its encapsulation into liposome and affection of this cytostatic cisplatin encapsulated in liposome on cancer cell lines. In literary recherche is detail description of these issues. Than is there specification of voltammetric methods, which serve to electrochemical detection of cisplatin. Based on literary recherche was chosen the best method for detection and subsequently the method was optimalized and than was applied to measuring itself.
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Study of influence of quantum dots to biological systmes and their components
Koudelková, Zuzana ; Zítka, Ondřej (referee) ; Provazník, Ivo (advisor)
The aim of this thesis is to summarize the available evidence about quantum dots and their effects on living systems. The text describes methods for the preparation of quantum dots with respect to their characteristics (size, fluorescence wavelength) and methods of quantum dots bio-functionalization of biomolecules. In living organisms is a large number of proteins, because these are considered as one of the main components of the interaction of organisms. Therefore, the work also provides basic information about proteins. Finally, there are described various methods by which the quantum dots may be characterized mainly by differential pulse voltammetry measurement zeta potential and fluorescence measurement. The main objective of this work is to propose models of different environments in which will be degradation of quantum dots with regard to the evaluation of acquired kinetic parameters for predicting the stability of individual quantum dots.
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Selected inorganic pollutants in foodstuffs
Kroupová, Kateřina ; Vítová, Eva (referee) ; Vitoulová, Eva (advisor)
This bachelor thesis is focus on occurrence of inorganic pollutants in foodstuffs. The introduction is dedicated to apperance of individual selected elements in foodstuffs. Concentration of these elements is very important factor for examination of toxic effects for the human organism. If we want to avoid the harmful effects to the human organism, we have to define border limits. Work is based on the legislative of Czech republic. Second part of this study is focused on the biological monitoring. The biological monitoring is important for precautionary measures. In the third part of this study are described toxical effects of these elements to the human organism. Before qualitative and quantitative analysis by instrumental techniques is important to properly take the sample. In the fourth and fifth part of this work are mentioned methods used for determination of these elements and metods of taking samples. This bachelor thesis provide complex view on the problems of pollutants in foodstuffs and it should be used as a base for following diploma thesis.
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Voltammetric determination of sulfathiazole on boron doped diamond electrode
Zich, Mikuláš ; Fischer, Jan (advisor) ; Schwarzová, Karolina (referee)
This bachelor thesis is dedicated to study of the electrochemically active substance sulfathiazole. Sulfathiazole is an antibacterial agent added to animal feed. As a result, it contaminates soil, water bodies and food. A boron-doped diamond electrode was chosen as the working electrode for voltammetric determination. First, the optimal pH for the study of sulfathiazole in the range of 2 to 12 by the technique differential pulse voltammetry was determined and the optimal pretreatment of the electrode before measurements. Subsequently, the calibration dependence was measured. Sulfathiazole was successfully dissolved in water at a concentration of c = 1·10-3 mol l-1 and Britton-Robinson buffer was used as the electrolyte. As the optimal pH was determined pH 6,0. At this pH, a relative standard deviation of sr = 5% was achieved. Standart deviation of 5 % has been achieved when the working electrode was polished before each measurement. Under these conditions, was calibration dependence measured in concentration range from 0,1 to 100 μmol l-1 . Linear dynamic range was calculated between 0,1 - 20 μmol l-1 . Limit of quantitation was found to be 97 nmol l-1 .
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The Use of Silver Rotating Disk Electrode to Suppress Passivation During Voltammetric Determination of 4-Nitrophenol
Pitřinec, Jakub ; Fischer, Jan (advisor) ; Vyskočil, Vlastimil (referee)
In this bachelor's thesis results of the optimization of the measurement of 4-nitrophenol (1·10-4 mol·l-1 ) in the Britton-Robinson (BR) buffer medium on the silver rotating disk electrode are presented with the aim of suppressing the passivation of the electrode surface. The parameters of the differential pulse voltammetry (DPV) technique were optimized for the analytical use of the rotating disk electrode. In BR buffer pH 4,0 and at the electrode rotation speed of 250 rpm calibration dependences of 4-nitrophenol was obtained in the range of (1-10) ·10-5 mol·l-1 under selected optimal conditions and different methods of electrode surface pretreatment. The limit of quantification (LOQ) achieved with polishing before each measurement was 1,7·10-6 mol·l-1 and with polishing only before the concentration change was 8,8·10-6 mol·l-1 .
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