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Humic Substances Characterization Employing High Resolution Ultrasonic Spectroscopy
Drastík, Martin ; Franců, Juraj (referee) ; Janoš, Pavel (referee) ; Pekař, Miloslav (advisor)
Předkládaná dizertační práce se zabývá využitím techniky vysoce rozlišovací ultrazvukové spektroskopie (HRUS) při analýze huminových látek, za účelem získání hlubšího vhledu do problematiky vztahu mezi jejich primárními charakteristikami (elementární složení a rozložení uhlíku ve funkčních skupinách) a agregačními vlastnostmi. V literární rešerši jsou shrnuty nejnovější poznatky z oblasti studia huminových látek a představeny základní principy HRUS. Dále jsou uvedeny základní informace z oblasti fraktální analýzy a její aplikace na data získaná pomocí různých metod při studiu huminových látek. První úkol experimentální části je zaměřen na výhodné využití HRUS pro výzkum huminových látek, zde reprezentovaných standardy Mezinárodní společnosti pro huminové látky (IHSS) a to sodnými solemi huminových a fulvinových kyselin. Fulvinové kyseliny v jejich protonované formě byly taktéž zkoumány a to z důvodu objasnění vlivu sodného kationu. Pro popis chování vzorků byla použita mocninná funkce, jejíž empirické parametry byly korelovány s primárními charakteristikami. Byla vytvořena metoda fraktální analýzy a následně byla aplikována na data získána ultrazvukovou spektroskopií. Data získaná pomocí ultrazvukové spektroskopie byla zpracována i alternativní metodou. Ta spočívala v globálním pohledu na závislost ultrazvukové rychlosti na koncentraci a využití lineární regrese. Druhým z cílů práce je získání informací o vlivu teploty na stabilitu agregátů HS (IHSS standardy). Byl zkoumán vliv teplotních gradientů na chování agregátů při čtyřech různých koncentracích. V třetí části práce pak byly zkoumány koncentrační závislosti u vzorků pocházejících především z lokalit příliš nezasažených lidskou činností. HRUS data byla proložena mocninnou funkcí a zkoumána pomocí fraktální analýzy. Takto získané parametry byly korelovány s primárními vlastnostmi. Ze znalosti hustoty při dané koncentraci mohly být stanoveny velikosti hydratačních obálek. Jak se v současné době ukazuje, informace o agregačním chování huminových biomolekul mohou být v budoucnu velmi důležité pro navrhování průmyslových aplikací huminových látek, zejména v zemědělství a v ochraně životního prostředí, ale také například v medicíně.
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Determination of Albendazole and Its Metabolites for Study of Anthelmintic Resistance
Belešová, Monika ; Kubíček, Vladimír (advisor) ; Drastík, Martin (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Monika Belešová Consultant: Ing. Vladimír Kubíček, CSc. Title of Thesis: Determination of Albendazole and Its Metabolites for Study of Anthelmintic Resistance An HPLC method suited for analysis of albendazole and two metabolites, i. e. albendazole sulfoxide and albendazole sulfone, in biological samples is described in this rigorous thesis. The aim of this work was to develop a new isocratic method for separation and determination of these substances using a core shell Kinetex PFP column equipped with pentafluorophenyl stationary phase. Based on preliminary experiments a mobile phase of acetonitrile+phosphate buffer (pH = 7.0) was used. Oxibendazole was exploited in the role of internal standard. The analytes and the internal standard were detected by means of a fluorescence detector. In the frame of the work the composition of the mobile phase was optimised and validation of the developed method was carried out. The validation results show the method to be applicable for the analyses of biological samples during intestinal parasite resistance against albendazole. The method was successfully applied to analyse real biological samples.
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SPE Utilization in Analysis of Benzimidazoles I
Janoušek, Jiří ; Kubíček, Vladimír (advisor) ; Drastík, Martin (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Jiří Janoušek Supervisor: Ing. Vladimír Kubíček, CSc. Title of diploma thesis: Use of SPE in analysis of benzimidazoles I Anthelmintic resistance in parasitic worms is an up-to-date topic. In order to combat this resistance we need to find proper analytic methods of its monitoring. The goal of this thesis is to find a suitable method of benzimidazole extraction, using a solid-phase extraction. During the experiments I used SPE tubes Supelco DSC-C8 (1ml, 100mg). In my thesis I tested the influence of pH and composition of elution agents on recovery of extraction. I performed the extraction in acid, neutral and basic environment. Elution agents consisted of a mixture of acetonitrile and polar phase, with four different mixing ratios. The best results were obtained during extraction in basic environment. For SPE tubes DSC-C8 the most suitable elution agent consisted of 4 parts of acetonitrile and 6 parts of 10% ammonia solution. Keywords: benzimidazoles, flubendazole, mebendazole, solid-phase extraction, resistance, anthelmintics
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Physico-chemical Properties of Newly Synthetized Drugs
Krčilová, Šarlota ; Kubíček, Vladimír (advisor) ; Drastík, Martin (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Šarlota Krčilová Consultant: Ing. Vladimír Kubíček, CSc. Title of Thesis: Physico-chemical Properties of Newly Synthetized Drugs Dissociation constants of some newly synthetized drugs based on pyrazine-2- carboxylic acid were measured in this diploma thesis. Three methods, having a sufficient instrumental background in the Department of Biophysics and Physical Chemistry, were proposed for the measurement, i. e. potentiometric method, spectrophotometry in UV-VIS region method and extraction spectrophotometry method. pK values of all studied substances were successfully determined by the potentiometric method, whilst each of the optic methods gave just one pK result. Hence a comparison of the three methods is not possible. Accuracy of the potentometric method results is documented by a very good agreement of the measured and literary pK values of pyrazine-2-carboxylic acid.
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The impact of deionized water drinking on human health
Mejtská, Jana ; Drastík, Martin (advisor) ; Kuchařová, Monika (referee)
CHARLES UNIVERSITY IN PRAGUE FAKULTY OF PHARMACY IN HRADEC KRÁLOVÉ DEPARTMENT OF BIOPHYSICS AND PHYSICAL CHEMISTRY BACHELOR THESIS THE IMPACT OF DEIONIZED WATER DRINKING ON HUMAN HEALTH Supervizor: Ing. MARTIN DRASTÍK, Ph.D. HRADEC KRÁLOVÉ, 2015 JANA MEJTSKÁ Abstrakt EN This bachelor thesis deals with suitability of drinking of deionized water, water deprived of minerals. The first part describes what basically water is and how it is important for each cell. Water helps transport oxygen to cells, transports waste matter and protects joints and organs. Afterwards the division of water into several groups is discussed. Drinking water is indispensable for human body. For that reason this issue is elaborated in the second part. The third part deals with distilled water, its composition and production. The fourth and the fifth parts, are dedicated to the possibilities of elemental analysis in water samples. The impact of deionized water on human health is fleshed out in the sixth part. The reasons why people drink deionized water as a part of their water intake are mentioned in this part, together with description of several studies performed on laboratory animals and volunteers. The seventh part is devoted to essential mineral substances and their crucial role for human body. The consequences of essential...
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Using of core-shell columns for miconazole determination
Hloušková, Martina ; Drastík, Martin (advisor) ; Kubíček, Vladimír (referee)
BSc. Martina Hloušková Supervisor: Ing. Martin Drastík, Ph.D. The aim of this diploma thesis was the optimization and validation of a HPLC method for miconazole determination in samples supplied by the Department of Pharmaceutical Technology. A gradual miconazole release dependent on the composition of the copolymere of glycolic and lactic acid was studied. HPLC analysis was performed using a modern core-shell Column Ascentis Express RP- Amide, 10 cm x 3.0 mm; 2.7 μm. Optimized analytical conditions were: mobile phase methanol:water 70:30, flow rate 0.8 ml/min, temperature 45 řC, injection 5 l and UV detection at 220 nm. Miconazole retention time was 5.65 min. The entire analysis was carried out in 7 minutes. When the optimal conditions of analysis were determined, the method could be validated. The following parameters were monitored during validation: linearity, selectivity, efficiency, LOD, LOQ, repeatability and tailing factor. All of the monitored parameters met the requirements of the Czech Pharmacopoeia.
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Simplification of terbinafine HPLC analysis of samples based on biodegradable polyesters
Malovaná, Andrea ; Drastík, Martin (advisor) ; Kubíček, Vladimír (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Andrea Malovaná Supervisor: Ing. Martin Drastík, Ph. D. Diploma thesis: Simplification of terbinafine HPLC analysis of samples based on biodegradable polyesters A HPLC method for determination of terbinafine in samples consisting of copolymers of lactic and glycolic acid was optimized and validated. The development of the method was based on the finding of suitable chromatographic conditions for separation of terbinafine. The separation was performed on the Ascentis Express ES-CN, 15 cm × 4.6 mm; 2.7 μm core- shell column. The mixture of the citrate phosphate buffer pH 4 and acetonitrile in ratio 40:60 (v/v) was chosen as the mobile phase. The mobile phase flow rate was set to 1.4 ml/min and the temperature to 30 řC. The injection volume of samples containing terbinafine was 5 µl. The UV detection at 226 nm was employed. The retention time of terbinafine was 3.3 min. The whole analysis was completed within 4 min. The method was validated, following parameters were tested: column efficiency, factor of symmetry, LOD, LOQ, linearity, repeatability and robustness. Keywords: terbinafine, HPLC, core-shell column, PLGA
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Multicomponent Analysis
Kovářová, Lucie ; Kubíček, Vladimír (advisor) ; Drastík, Martin (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Lucie Kovářová Supervisor: Ing. Vladimír Kubíček, CSc. Title of Diploma Thesis: Multicomponent analysis This diploma thesis deals with the determination of concentrations of individual dyes in mixtures by multicomponent spectrophotometric analysis. The method was tested on selected dyes which were divided into two groups. The first group contains methyl orange, methyl red, orange II and phenol red. The second group consists of methylene blue, bromocresol green and thymol blue. Within each group mixtures were prepared containing combinations of two, three and four dyes in various ratio. Spectra of prepared mixtures were measured by diode array UV/VIS spectrophotometer. Absorbance values were read at wavelengths of absorption maxima of the individual dyes. Using the pseudoinverse matrix, concentration ratios of components were calculated from the absorbance values. The determination in determined and over determined systems was performed. On the basis of the results obtained by the method of analysis it is possible to determine the individual concentration of the multi-component dyes mixtures without prior separation. Keywords: spectrophotometry, multicomponent analysis,...
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Using of core-shell columns for fluconazole determination
Brokešová, Kateřina ; Drastík, Martin (advisor) ; Kubíček, Vladimír (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Kateřina Brokešová Supervisor: Ing. Martin Drastík, Ph. D. Thesis title: The use of core-shell columns for fluconazole determination A novel HPLC method for determination of fluconazole in dissolution test samples was developed and partly validated. A matrix formed by lactic and glycolic acid copolymer branched by different compounds was used as a drug carrier. Fluconazol was incorporated as the model drug. The concentration profile of fluconazole was studied by developed HPLC method during the dissolution test. A modern core-shell column Ascentis Express RP-Amide, 10 cm × 3.0 mm; 2.7 μm was employed. A mixture of acetate buffer pH 5.0:methanol (80:20) served as the mobile phase. The flow rate was 0.70 ml/min and the detection wavelength was 260 nm. The temperature of analysis was 50 řC. The retention time of fluconazole was 3.3 min and the whole analysis took just 4 min. Keywords: fluconazole, core-shell column, HPLC, PLGA
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