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Detached house on a sloped site
Schwarzová, Klára ; Jelínek, Petr (referee) ; Šuhajdová, Eva (advisor)
Bachelor thesis deals with the design of the house on a slope and the development of its project documentation. The building stands on a plot number 2375/48 in the administrative area of Rožnov pod Radhoštěm in the street Dubkova. It is a building with two floors and a basement. House is suitably designed for a young family with two children with the range of two children's rooms, bedrooms for parents, living room connected with kitchen and exit to the terrace. Furthermore, we can find a bathroom, toilet, HVAC and utility room, cloakroom, pantry and garage for one car. The cellars are accessible only from the outside and will be used for storage of garden tools. The house is based on concrete strip footings. Vertical structures are formed with calcium silicate blocks SENDWIX. The gable roof has a slope of 31 °.
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Mountain pension with a restaurant
Schwarzová, Klára ; Sobotka, Jindřich (referee) ; Šuhajdová, Eva (advisor)
It is a mountain inn with restaurant, situated in the village Pstruží. The building has a footprint L. partial basement and has two floors. The object is divided into a public part and the operating part, which is the operation of the restaurant. The roof is pitched with a slope of 35 °. On the second floor are offices leadership pension. In the basement there is a technical background.
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Development of electroanalytical methods for detection of cholesterol, 7-dehydrocholesterol and cholecalciferol
Benešová, Lenka ; Schwarzová, Karolina (advisor) ; Navrátil, Tomáš (referee) ; Šelešovská, Renáta (referee)
Steroidival substances are an integral part of the human organism, such as bile acids, steroid hormones, vitamins. The most important sterol in whole organism is cholesterol, which is cornerstone of the all cell membranes. It is involved in important processes in the body, but its storage in blood vessels in the formo f low-density lipoprotein (LDL) is crucial of reason serious health diseases as atherosclerosis, myocardial infarction and others. 7-dehydrocholesterol is a precursor of cholesterol and another sterol compound studied by me, cholekalciferol, also known as a vitamin D3. Deficiency of 7-dehydrocholesterol reductase is the main indicatior of the possible genesis of Smith-Lemli-Opitz syndrome. One of the goals of this thesis was developed a suitable electrochemical method to facilitate the diagnosis of this syndrome from plasma and amniotic fluid in the prenatal and postnatal phases of pregnancy. Within the framework of this thesis were developer electrochemical methods in a batch and flow arrangement for detection of the above-mentioned sterols, namely cholesterol, 7-dehydrocholesterol and cholekalciferol. It was wokered in the medium contain perchloric acid or its salt sodium perchlorate in acetonitrile as supporting electrolyte. It was worked in the wide range of working disc...
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Electrochemical behaviour of {110}-oriented single crystal boron-doped diamond electrode for electroanalysis
Poláková, Jana ; Schwarzová, Karolina (advisor) ; Fischer, Jan (referee)
This bachelor thesis deals with the study of the electrochemical behavior of the neurotransmitter dopamine on mechanically polished single crystal boron-doped diamond electrodes with crystal orientation {110} and the boron-to-carbon (B/C) ratio in the gas phase during the chemical vapor deposition process at 250, 500, 1000 and 2000 ppm. Measurements were carried out on mechanically polished, O-terminated and H-terminated electrodes. The redox inner-sphere markers [Fe(CN)6]3−/4− and dopamine/dopamine-o-quinone and the outer- sphere marker [Ru(NH3)6]3+/2+ were used for electrochemical characterization of the polished electrode surface by cyclic voltammetry. As the B/C ratio increases for inner-sphere redox systems, ΔEp values decrease due to the acceleration of heterogeneous electron transfer kinetics. The high values of potential differences indicated that DA behaves quasi-reversibly at BDD electrodes. The ΔEp values for [Ru(NH3)6]3+/2+ showed no trend, confirming the independence of this marker at the doping level. Repeatability was further investigated when several measurements are performed in succession, with the DA solution being stirred before each measurement. It was found that when the solution is stirred, the current response does fluctuate (sr = 9.20), but the potential shows very low...
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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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Voltammetric detection of 7α-hydroxycholesterol on boron doped diamond electrode
Serbanová, Lucie ; Schwarzová, Karolina (advisor) ; Nesměrák, Karel (referee)
This bachelor's thesis is dedicated to the electrochemical determination of 7α-hydroxycholesterol (7α-OHC) using boron-doped diamond electrode (BDDE). The work includes the optimization of experimental conditions and the measurement of the concentration dependence of 7α-OHC. The influence of various factors, such as water content in the solution and scan rate, on the electrochemical response of 7α-OHC was investigated. Various electrochemical methods, including cyclic voltammetry and differential pulse voltammetry, were used in the experiments. The electrochemical behavior of 7α-OHC in a solution of chloric acid and acetonitrile were analyzed. Important factors such as electrode passivation and response stability were carefully evaluated. The measurement of concentration dependence of 7α-OHC exhibited a linear response within the concentration range from 2∙10−5 mol l−1 to 1∙10−4 mol l−1 . Limits of detection (LOD) and quantification (LOQ) of 1,33 µmol l−1 and 4,43 µmol l−1 were determined. Comparison with other methods revealed that the electrochemical determination of 7α-OHC on BDDE achieves comparable sensitivity. The results of this work provide crucial insights into the electrochemical behavior of 7α-OHC, highlighting the advantages of BDDE for sensitive and reliable determination of...
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Electrochemical study of the DNA desorption from the surface of carbon electrodes
Průcha, Jakub ; Dejmková, Hana (advisor) ; Schwarzová, Karolina (referee)
This bachelor's thesis deals with the possibility of DNA desorption from the surface of carbon electrodes. Measurements were performed using linear scan voltammetry in a three- electrode configuration, with single-stranded DNA (ssDNA) of 31 nucleotides as the sample. The working electrodes were a boron-doped diamond electrode and an electrode made of highly oriented pyrolytic graphite. The efficiency of desorption was assessed by comparing the heights of oxidation signals of adsorbed nucleic bases, which were measured before and after the application of the desorption procedure. The first approach involved desorption through mixing or rinsing in solutions with different properties, specifically in organic solvents: methanol, acetone, toluene, and DMSO; in acids and bases: HCl, HNO3, NaOH; and subsequently in surfactants and detergents: Triton X-100, TWEEN 80, CTAB, and Tergazyme. Among the tested substances, a 0.1 mol·l-1 solution of NaOH and a 1 % solution of Tergazyme proved to be effective. Subsequently, the time and temperature dependence of the rinsing strength of these two solutions on ssDNA desorption were examined. From the conducted experiments, it was determined that time and temperature of the solution do not increase the efficiency of the desorption by NaOH solution. For rinsing with a...
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Study of redox and adsorption features of bile acids on hanging mercury drop electrode
Yershova, Polina ; Schwarzová, Karolina (advisor) ; Gajdár, Július (referee)
Bile acids are the end products of cholesterol metabolism and are important biological surfactants. The curved shape of their chains allows the cyclization of molecules, and the formation of a supramolecular structure. The goal of this thesis was to study the electrochemical and adsorption behavior of selected bile acids: lithocholic, deoxycholic and cholic acids. The measurements were carried out in the medium Brittonův-Robinson buffer:methanol in the ratio 9:1 using cyclic voltammetry and AC voltammetry methods and measuring the dependence of the differential capacitance Cd on the applied potential E. A hanging mercury drop electrode was used as a working electrode. The measurements showed that bile acids are adsorbed on the surface of the electrode and organizing themselves in self assembled monolayers (SAM). In our case we have observed formation of 2D condensed layers as specific form of SAM. Transfer techniques were used to demonstrate bile acid adsorption. A study of the behavior of lithocholic acid as a function of different pH values showed that only at pH 10.0 to 12.0 2D 2D condensation occurs, i. e. that at pH values in the range of 2.0 to 9.0 it is another type of adsorption. On AC voltammograms, there are a maximum of two areas in which peaks occur: the first is around -0.2 V and the...
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A new approach to the electroanalysis of primary bile acids and related steroids
Klouda, Jan ; Schwarzová, Karolina (advisor) ; Skopalová, Jana (referee) ; Vyskočil, Vlastimil (referee)
In this doctoral thesis, a novel method for the determination of primary bile acids cholic acid and chenodeoxycholic acid is presented. Bile acids play various vital roles in the mammalian body. Moreover, their determination is extremely helpful in liver and biliary disease diagnosis and management. These saturated organic compounds lack strong chromophores and fluorophores in their structure, and thus are usually hard to detect in spectroscopy. For this reason, either instrumentally advanced but expensive methods, such as mass spectrometry, or less reliable enzymatic methods are commonly employed in bile acids quantitation. Hence, the demand for simple and reliable methods for their determination is strong. Bile acids are also known to be virtually inert for direct electrochemical oxidation. Herein, a simple method for their chemical activation for electrochemical oxidation on bare electrode materials was developed, optimized and applied to cholic acid and chenodeoxycholic acid determination. The activation is based on a dehydration reaction of a primary bile acid with 0.1 mol L-1 HClO4 in acetonitrile (water content 0.55%) that introduces double bond(s) into the originally fully saturated steroid core. This naturally increases the electron density in the structure, and thus allows electrochemical...
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Development of voltammetric methods for detection of phytosterols on carbon-based electrodes
Zelenský, Michal ; Schwarzová, Karolina (advisor) ; Fischer, Jan (referee)
The aim of this diploma thesis was to develop an electrochemical method for three phytosterols, namely stigmasterol β-sitosterol and ergosterol using voltammetry techniques on glassy carbon electrode and boron doped diamond electrode. The work builds on previous results, where it was shown that the electrochemical oxidation of phytosterols requires perchloric acid in acetonitrile. When this acid is used, a dehydration reaction occurs. Calibration dependences were measured here for all phytosterols in an environment with a water content of 0.43%. The stability of the signal with increasing distilled water content was further investigated. Then the calibration dependences in the increased water content were measured again. If we want to use HPLC-type separation techniques, we must first find out how the phytosterols will behave in this environment, and therefore the signal stability on the buffer content was investigated. The buffers used were phosphate and acetate buffer. Subsequently, the concentration dependence was measured in an environment with a higher content of phosphate buffer. Furthermore, the possibility of detecting two phytosterols at once was investigated. Key words: dehydration, glassy carbon electrode, boron doped diamond electrode, oxidation, phytosterols, voltammetry
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