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Analysis of biologically active compounds using high performance separation methods
Adamusová, Hana ; Bosáková, Zuzana (advisor) ; Jelínek, Ivan (referee) ; Tůma, Petr (referee)
In the first part of this doctoral thesis, a new analytical HPLC-MS/MS method for monitoring of concentration changes of 17β-estradiol (βE2) during in vitro mouse sperm capacitation was developed. Capacitation was performed for three initial concentrations of βE2 (200, 20 and 2 μg/L). For all the concentrations a similar trend for the total unbound βE2 was observed. In general, the βE2 concentration decreased to reach its minimum and then increased again. The position of the minimum differed for the individual tested βE2 concentrations. Experimentally obtained results were subjected to the kinetic analysis. The curves fitted through the experimentally determined points displayed an autocatalytic character. For the agreement between the curves obtained by fitting through the experimental points and the theoretical calculated curves, it is necessary to assume that the first step is adsorption of βE2 onto the surface of the sperm controlled by Langmuir isotherm. The kinetic study was also used to study the effects of fluorides and aluminium fluoride complexes on the capacitation of mouse sperm. The experimental points were in very good agreement with the shape of the theoretical curves and this fact verifies the mechanism of the mouse sperm capacitation kinetics. In the second part of this work, two...
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Multidisciplinary characterization of interactions between oestrogen hormones and their receptors during sperm capacitation.
Bosáková, Tereza ; Komrsková, Kateřina (advisor) ; Smrček, Stanislav (referee) ; Postlerová, Pavla (referee)
This doctoral thesis was focused on the multidisciplinary characterizatrion of interactions between hormones and their receptors during sperm capacitation, which is the final step in sperm maturation in mammals and the key event to achieve egg fertilization. Three oestrogenic hormones (17β-estradiol (E2), 17α-estradiol (αE2), 17α-ethynylestradiol (EE2)), which are part of environmental pollution, were selected for the study. These hormones are called endocrine disruptors as they can cause disorders of the hormonal system in animals, thereby adversely affecting physiological processes, including reproduction. A new analytical HPLC-MS/MS method was developed for monitoring of concentration changes of oestrogens (E2, αE2 and EE2) during time-dependent capacitation of mouse and rat sperm in vitro. For individual oestrogens, the concentration dependences of free, unbound hormone on the capacitation time were measured for three concentrations of individual hormones (200, 20 and 2 μg/L). The obtained concentration data were converted into values of relative concentrations, which were subjected to kinetic analysis. Kinetic models were proposed for the interaction of individual hormones with sperm, which were described by a system of differential equations with optimization of rate constants and molar...
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Determination of creatinine using pulsed amperometry
Giampaglia, Dominika ; Dejmková, Hana (advisor) ; Schwarzová, Karolina (referee)
This diploma thesis deals with the determination of creatinine using a combination of flow injection analysis (FIA) or high-performance liquid chromatography (HPLC) with pulse amperometry, an electrochemical technique based on the application of potential pulses on a gold working electrode. The determination was performed in a basic environment of borate buffer with creatinine concentration of 1∙10-4 mol∙l-1 . The lenght of the cleaning and activation pulse was optimized as well as the pH of the running buffer. A cleaning pulse of +1.8 V was first applied to the electrode for 100 ms, then an activation potential of -0.5 V was applied for 150 ms and then a measuring potential of +0.2 V for 300 ms. The optimal pH was selected as pH=9,4. Methanol and acetonitrile were added to the borate buffer to test whether creatinine could be determined in presence of these organic solvents and whether flow injection analysis could be transformed into HPLC. Methanol in the system caused peak deformation, acetonitrile did not cause the peak deformation in the system, at higher contents the baseline was destabilized. Furthermore, the calibration dependence in the range of concentrations from 2.5∙10-4 mol∙l-1 to 5∙10-6 mol ∙ l-1 was measured using PAD in combination with FIA. At higher concentrations, peaks splitted....
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Comprehensive analysis of warning and defense compounds of true bugs by high-performance separation methods
Krajíček, Jan
Insects have developed many strategies of defence against predators in the course of evolution. The evolutionarily oldest and most widely used type of defence is chemical defence, followed by acoustic or optical defence. However, many species of insects use simultaneously multiple types of warning signals, which affect different sensory receptors of the given predator. Such a complex method of warning signals is called multimodal method. It may consist of a combination of simultaneous chemical and optical signals, or a combination of acoustic and optical signalling. The combination of chemical and optical signalling used against a predator is probably the most common form of multimodal signalling. The presented work deals with the analysis of biologically active substances, which participate in the defence mechanisms of a widespread species of insects - true bugs (Heteroptera). Pterin derivatives represent a large group of natural compounds derived from pteridin, bicyclic heterocycle, and they are found in virtually all living organisms from bacteria to vertebrates. In insects, they primarily serve as pigments, resulting for example in striking coloration of cuticles of Heteroptera. The first part of the dissertation was focused on identification and quantification of pterin derivatives in cuticles...
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Determination of acrylamide in coffee by high performance liquid chromatography
Vajdíková, Tereza ; Vítová, Eva (referee) ; Diviš, Pavel (advisor)
The bachelor's thesis aimed to optimize the method of determining acrylamide in coffee using high-efficiency liquid chromatography with a diode-array detector. In the theoretical part of the bachelor's thesis, attention was paid to the taxonomic distribution of coffee, it's processing and chemical composition. Part of the theoretical frequency of the work involved describing the formation of acrylamide in coffee and possible methods of determining it. The practical part looked at validating the method, which was used in the analysis of coffee samples. The individual samples of coffee varied in the type of coffee and the societies where the coffee was obtained. Determination of the acrylamide content has been carried out on commercial, franchised, and selective coffees of the arabica species. Finally, the determination of acrylamide was made in the coffee of various types, in robusta and arabica.
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Use of plasma for degradation of ibuprofen in water
Bača, Ondřej ; Landová, Pavlína (referee) ; Mravcová, Ludmila (advisor)
This Bachelor’s thesis deals with the current problem of increasing concentrations of nonsteroidal anti-inflammatory drugs in water. The concentration increase of these drugs is due to rised anti-inflammatory drugs intake in modern era. Wastewater treatment plants are not capable of sufficient elimination of these drugs in wastewater. That leads to contamination of groundwater and surface water. The long-term impacts of these drugs on human health is not fully understood, so it is necessary to develop new methods, which will lead to complete degradation of nonsteroidal anti-inflammatory drugs and other pollutants. Theoretical part of the Bachelor’s thesis focuses on description and properties of nonsteroidal anti-inflammatory drugs and their consumption in the Czech Republic. Furthermore, the paper deals with advanced oxidation processes especially with plasma. This part of the paper also deals with determination of nonsteroidal anti-inflammatory drugs in water. For degradation of ibuprofen was used plasma. During the plasma treatment, samples were taken in regular time intervals, which were afterwards determined by an appropriate analytical method LC-ESI-MS. The results were compared with scientific studies dealing with this topic.
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Voltammetric and Amperometric Determination of Nitrophenols Using Boron-Doped Diamond Film Electrode
Karaová, Jana ; Barek, Jiří (advisor) ; Šelešovská, Renáta (referee) ; Jaklová Dytrtová, Jana (referee)
Presented Ph.D. Thesis is focused on the use of the boron-doped diamond (BDD) electrodes for voltammetric and amperometric determination of selected nitrophenols: 2-nitrophenol (2NP), 4-nitrophenol (4NP), and 2,4-dinitrophenol (2,4DNP). These compounds are listed as "priority pollutants" by United States Environmental Protection Agency (US EPA) due to their negative impact on living organisms and are mainly used in agriculture as plant growth stimulators. BDD electrodes are used for determination of wide range of electrochemically both reducible and oxidisable organic compounds and have become a popular electrode material thanks to its commercial availability and excellent mechanical and electrochemical properties. A differential pulse voltammetric method was developed for the determination of 2NP, 4NP and 2,4DNP at a BDD film electrode using electrochemical reduction and of 4NP and 2,4DNP using electrochemical oxidation. The method was successfully applied for the direct determination of these compounds in drinking and river water in the concentration range from 4×10-7 to 2×10-5 mol.L-1 . To improve the limit of quantification, a preconcentration by solid phase extraction from 100 mL (drinking and river water) and 1000 mL (drinking water) of water samples was used with limit of determination...
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Biomarkers of early renal injury
Fořtová, Magdaléna ; Průša, Richard (advisor) ; Kalousová, Marta (referee) ; Ryšavá, Romana (referee)
Aims: The thesis deals with the biomarkers of early renal injury, namely albuminuria and neutrophil gelatinase-associated lipocalin (NGAL). The aims in the case of albuminuria were the implementation of HPLC method, comparing HPLC with immunoturbidimetric (IT) method and monitoring the relationship to the diagnosis of diabetes mellitus. The aim of urinary NGAL (and eventually other markers) examination was to verify its reliability in the prediction of acute kidney injury (AKI). Methods: We investigated albuminuria in fresh urine samples in the groups of 636 diabetics and 456 nondiabetics using the HPLC method (Agilent 1200, Agilent Technologies, USA) and immunoturbidimetrically (Cobas Integra 400, Roche Diagnostics); we studied the correlations and relationships between albuminuria and glycated hemoglobin HbA1c. We investigated urinary NGAL by chemiluminescent microparticle immunoassay (Architect i4000, Abbott) in children's groups: 1) after renal transplantation (N = 15), 2) with acute or chronic kidney disease (N = 28); and in adult patient's groups: 1) after cardiac surgery (N = 10) and 2) post angiography (N = 41). Results: Albuminuria determined by HPLC was statistically significantly higher than albuminuria determined by IT. We excluded nonspecificity of the HPLC method. Results indicate...
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Chromatograhic characterization of chiral and achiral separation systems
Kučerová, Gabriela ; Tesařová, Eva (advisor) ; Čabala, Radomír (referee) ; Ševčík, Juraj (referee)
Dissertation thesis is a 5-publications' collection concerning characterization and application potential of cyclodextrins, polysaccharides and macrocyclic antibiotics based chiral stationary phases. The effects of stationary phase and mobile phase are studied. This approach ensures the complex insight into separation systems studied. Systems with different nature of chiral selector were studied by HPLC. Namely, macrocyclic antibiotics and derivatized polysaccharides were used for experiments. Former ones provided better results for enantioseparation of non-coded amino acids than latter ones. Dynamic coating procedure was used for preparation of a new chiral stationary phase. Characterization of new cationic cyclodextrin based chiral stationary phase was performed. Linear free energy relationship method was used for characterization of two different separation systems, i.e. newly prepared stationary phase and commercially available stationary phase. Based on results obtained, newly prepared stationary phase showed better results for separation of different achiral groups of analysts. New stationary phase prepared by dynamic coating was compared with chromatographic system, in which the chiral selector was used as a mobile phase additive. The chiral selector used for the two different approaches was...
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Analysis of biologically active compounds using high performance separation methods
Adamusová, Hana ; Bosáková, Zuzana (advisor) ; Jelínek, Ivan (referee) ; Tůma, Petr (referee)
In the first part of this doctoral thesis, a new analytical HPLC-MS/MS method for monitoring of concentration changes of 17β-estradiol (βE2) during in vitro mouse sperm capacitation was developed. Capacitation was performed for three initial concentrations of βE2 (200, 20 and 2 μg/L). For all the concentrations a similar trend for the total unbound βE2 was observed. In general, the βE2 concentration decreased to reach its minimum and then increased again. The position of the minimum differed for the individual tested βE2 concentrations. Experimentally obtained results were subjected to the kinetic analysis. The curves fitted through the experimentally determined points displayed an autocatalytic character. For the agreement between the curves obtained by fitting through the experimental points and the theoretical calculated curves, it is necessary to assume that the first step is adsorption of βE2 onto the surface of the sperm controlled by Langmuir isotherm. The kinetic study was also used to study the effects of fluorides and aluminium fluoride complexes on the capacitation of mouse sperm. The experimental points were in very good agreement with the shape of the theoretical curves and this fact verifies the mechanism of the mouse sperm capacitation kinetics. In the second part of this work, two...
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