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The use of electrochemical oxidation in abacavir degradation studies
Pražáková, Lucie ; Kubíčková, Anna (advisor) ; Kozlík, Petr (referee)
The focus of this bachelor's thesis is the electrochemical degradation of abacavir. Abacavir is the active pharmaceutical ingredient of the medicine for human immunodeficiency virus (HIV). It was developed an electrochemical method for the oxidation of abacavir, including its excipients found in Ziagen tablets given to patients. Abacavir at a concentration of 0,15 mg·cm-3 was oxidized electrochemically at a constant potential (1,15V) on a specially assembled three-electrode apparatus. Subsequently, the quantity and type of the resulting products were analysed by a previously optimized chromatography method. The oxidation was relatively fast. After 7 minutes about 20 % of abacavir was oxidized. Two oxidation products were formed and their structures were confirmed by mass spectrometry.
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Development of an UHPLC method for stability study of venetoclax
Máchalová, Jitka ; Křížek, Tomáš (advisor) ; Kozlík, Petr (referee)
Tato práce se zabývá vývojem chromatografické metody pro stanovení venetoclaxu a kontrolu jeho čistoty pomocí techniky UHPLC. Venetoclax je nízkomolekulární inhi- bitor antiapoptického proteinu Bcl-2, který hraje důležitou roli při regulaci apoptózy a při vzniku hematologické malignace. Venetoclax se tedy používá pro léčbu chronické lymfocytární leukemie. Kvůli problematické rozpustnosti analytu byl jako rozpouště- dlo vzorku zvolen 10mM vodný roztok H3PO4 : ACN s 40% objemovým zastoupením acetonitrilu. Dále byla nalezena optimální kombinace stacionární a mobilní fáze. Optimalizace byla prováděna především s ohledem na faktor chvostování píku vene- toclaxu a jeho rozlišení od nečistoty eluující v jeho těsné blízkosti. V optimalizované metodě byla použita kolona Acquity UPLC BEH Phenyl (100 × 2,10 mm; 1,7 µm) a jako mobilní fáze směs pufru (10mM H3PO4/NH3 o pH 2,5) s přídavkem 0,5% trifluoroctové kyseliny a ACN. Součástí validace metody bylo testování přesnosti, opa- kovatelnosti, meze detekce a kvantifikace, linearity a lineárního dynamického rozsahu, robustnosti metody a testování stability vzorku. Opakovatelnost retenčního času byla 0,07 % a opakovatelnost plochy píku byla 0,45 %. Hodnota meze detekce metody byla 1,6 · 10−5 mg mm−1 a hodnota meze kvantifikace byla 5,4 · 10−5 mg mm−1 . Linearita...
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Liquid Chromatography Methods for Analysis of Actinomycete Secondary Metabolites - Potential Antibiotics
Kameník, Zdeněk ; Nesměrák, Karel (advisor) ; Cvačka, Josef (referee) ; Bosáková, Zuzana (referee)
(EN) This dissertation thesis contains scientific results achieved in the field of analytical chemistry, particularly liquid chromatography. The major part of the results has been published in prestigious international journals in five papers. In addition to that, relevant yet unpublished results have been included as well. In general terms, the work presented here contributed to the concerted efforts to tackle the current lack of novel antibiotics. Specifically, high-performance liquid chromatography (HPLC) and ultra high-performance liquid chromatography (UHPLC) techniques coupled to a variety of detection systems have been employed for analysis of antibiotics and actinomycete secondary metabolites. The first thematic part describes the development of liquid chromatography methods for analysis of lincomycin precursors, lincomycin precursor analogues, and lincomycin derivatives. The methods have been applied to study lincomycin biosynthetic pathway and obtain improved lincomycin derivatives by mutasynthesis. The second thematic part aims at investigating alternative approaches for analysis of antibiotics. Firstly, the core-shell particle and the sub-2 μm particle chromatographic columns were compared. The core-shell particle columns compatible with HPLC proved to be a convenient alternative to the...
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Antioxidanty v čajích
Polanský, Petr
This thesis discusses about antioxidants in teas. In the first part I deal with description of a tea tree and a tea. I closely describe processing of tea leaves, their quality, their composition and impact of the tea on human health. In the second part I describe polyphenols and their laboratory determination. In the next part I deal with practical measurements in total of 12 teas, two mate and two rooibos. I determine total content of polyphenols by a method FCM and by a method UHPLC and the antioxidant capacity by a method TAA. The highest content of polyphenols and the highest antioxidant capacity were measured in the oolongs and the green tea Sencha HBO. The lowest results appeared in both puerh, except the results from the method UHPLC, where they belonged among the best ones. Mate and rooibos with their total content of polyphenols and antioxidant capacity approached for example white or black tea.
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Distribution of pharmaceuticals in wastewater treatment plants
Šilhánková, Lenka ; Čáslavský, Josef (referee) ; Vávrová, Milada (advisor)
This bachelor’s thesis deals with a trending topic – wastewater distribution of pharmaceuticals proven to be toxic to non-target organisms – specifically, the occurrence of beta-blockers, plentifully used in treating hypertension and other cardiovascular diseases, is discussed. Members of this group, Atenolol, Acebutolol and Bisoprolol were chosen for closer study. The elimination of these chemicals was observed in three wastewater treatment plants (WWTP) with different treatment technologies and various number of population equivalents. For said analytes, UHPLC with UV/VIS detection using diode array detector (DAD) method was optimalised. A part of this thesis also deals with optimalization of isolation and concentrating the analytes. Unfortunately, the described method was not suitable for real sample analysis, because in most samples, the limit of quantification or even the limit of detection was not exceeded. It would be best for an analytical method with higher sensitivity, e. g. mass detector, to be used. The data gained in this experiment do not hold any informational value about the effectiveness of WWTP, as the exact amount of Acebutolol in effluent was measured only in one case. Based on the to-date executed analysis, it is impossible to conclude whether the quality of the treated water, concerning the content of aforementioned pharmaceuticals, is in any way ideal.
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Determination of NSAIDs in wastewater
Krůzová, Sabina ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
The thesis focuses on non-steroidal anti-inflammatory drugs in wastewater. It characterizes drugs and defines specific methods of determination naproxen and ibuprofen in wastewater. Besides their characteristics there are pre-analytics and final analytic methods described here which are used for determination of drugs in wastewater. To analyse we used wastewater from Veterinary and Pharmaceutical University in Brno. Samples were filtered and concentrated by solid phase extraction (SPE) and after that they were analysed by UHPLC with diode array detector. Thanks to these practices and methods, there were found, that concentration of naproxen in wastewater from VFU Brno was below the limit of quantification and ibuprofen wasn´t detected in most of cases.
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Preparation of hyaluronan oligosaccharides with N-acetylglucosamine at both ends of the chain using enzymatic catalysis
Gadová, Martina ; Hermannová,, Martina (referee) ; Šílová, Tereza (advisor)
This bachelor thesis deals with preparation of odd-numbered hyaluronan oligosaccharides with N-acetylglucosamine at both ends of the chain using enzymatic catalysis by -Glucuronidase. The theoretical part focuses on present knowledge of hyaluronic acid and it fragments. It focuses on properties, enzymatic hydrolysis, application in different branches of science, but also analysis of oligosaccharides. One chapter is devoted to properties of enzyme -Glucuronidase. The experimental part deals with preparation of oligosaccharides type HANN. The reaction conditions for preparation of HA oligosacharides were optimized (pH, temperature) and the progress of enzymatic hydrolysis and the mixture composition after digestion were monitored by method UHPLC.. After optimization the mixture of oligosaccharides HANN was prepared and consenquently it was analysed by methods UHPLC and LC-MS. All the data were acquired in company Contipro Pharma, a.s., Dolní Dobrouč, Czech republic.
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Assessment of drugs in settlings with waste water treatment
Hájek, Radek ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
This bachelor thesis is focused on asessment of pharmaceuticals in wastewater treatment plant sludge. Two macrolide antibiotics (erythromycin and clarithromycin) and three non-steroidal anti-inflammatory drugs (ibuprofen, naproxen and diclofenac) were assessed. Sample of sludge was taken in municipal wastewater treatment plant in Brno-Modřice. Analytes were obtained using pressurized solvent extraction (PSE) or ultrasonic solvent extraction (USE). Clean-up was performed by solid phase extraction (SPE). Ultra high performance liquid chromatography followed by UV-VIS diode array detection was used for quantitative determination of the analytes.
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