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Analysis of the degradation products of the active substances in historical pharmaceutical relicts from 18th and 20th century.
Čambal, Peter ; Nesměrák, Karel (advisor) ; Kubíčková, Anna (referee)
Historical pharmaceutical preparations analyzed in this thesis were a senna extract more than 200 years old, an ointment "Naso-Merfen" 75 years old, and an ointment "Sulfathiazol" 42 years old. The active substances in the analyzed samples were sennosides A and B (senna extract), ephedrine and menthol (the ointment "Naso-Merfen"), and sulfathiazole (the ointment "Sulfathiazol"). The senna extract was analyzed by RP-HPLC and HPLC-MS. Separation conditions were optimized, especially for separation of the sennoside A and B enantiomers. The active substances were not detected in the sample. One degradation product and substances characteristic for senna were identified. Their presence in the historical and contemporary sample was compared. Detailed ESI− -MSn fragmentation mechanisms of sennoside A and B have been proposed. The sample of the ointment "Naso-Merfen" was analyzed by HILIC-UV, HPLC-MS, GC-MS, and AAS. Separation conditions were optimized. The active substances were quantified. Degradation products of the active substances were not detected in the sample. The sample of the ointment "Sulfathiazol" was analyzed by RP-HPLC and HPLC-MS. Separation conditions were optimized. The active substance was quantified. Degradation products of the active substance were not detected. The authenticity of...
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Analysis of the composition and degradation of pharmaceutical substances and pharmaceutical preparations from the 18th and 20th centuries
Kudláček, Karel
The dissertation focused on the analysis of twenty historical remains of pharmaceutical substances and pharmaceutical preparations dating to the 18th and 20th century by liquid and gas chromatography with UV-spectrometric or mass spectrometric detection. The analytical approach was chosen with regards to the age and pharmaceutical forms of the analyzed historical remain. The authenticity of the sample was verified by identifying the active ingredients, their possible degradation products and other excipients by tandem mass spectrometry. The fragmentation of some analytes was also studied by tandem mass spectrometry. The stability of historical pharmaceutical preparations from the 20th century was assessed on the basis of a decrease in the concentration of active substances compared to the content declared by the manufacturer or, in case of historical pharmaceutical remains from the 18th century, on the basis of active substance concentrations determined in the historical residue and current reference material. A multi-analytical approach combining five analytical methods, the results of which complement each other, was used to analyze the historical remains of ointments. While the active substances identified in ipecacuanha were found to be partially degraded, they were completely degraded in senna...
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Pathology and physiology of de novo purine synthesis.
Krijt, Matyáš ; Zikánová, Marie (advisor) ; Šebesta, Ivan (referee) ; Čajka, Tomáš (referee)
Purines are organic compounds with miscellaneous functions that are found in all living organisms in complex molecules such as nucleotides, nucleosides or as purine bases. The natural balance of purine levels is maintained by their synthesis, recycling and degradation. Excess purines are excreted in the urine as uric acid. Purine nucleotides may be recycled by salvage pathways catalysing the reaction of purine base with phosphoribosyl pyrophosphate. A completely new central molecule of purine metabolism, inosine monophosphate, can be synthesized from precursors during the de novo purine synthesis (DNPS). DNPS involves ten steps catalysed by six enzymes that form a multienzymatic complex, the purinosome, enabling substrate channelling through the pathway. DNPS is activated under conditions involving a high purine demand such as organism development. Currently, three DNPS-disrupting disorders have been described: ADSL deficiency, AICA-ribosiduria and PAICS deficiency. All three disorders are caused by genetic mutations leading to the impaired function of particular enzyme causing insufficient activity of respective DNPS step, manifested biochemically by accumulation of substrate of deficient enzyme, biologically by disruption of purinosome formation and clinically by unspecific neurological features,...
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Analysis of the composition and degradation of pharmaceutical substances and pharmaceutical preparations from the 18th and 20th centuries
Kudláček, Karel ; Nesměrák, Karel (advisor) ; Bosáková, Zuzana (referee) ; Gabriel, Jiří (referee)
The dissertation focused on the analysis of twenty historical remains of pharmaceutical substances and pharmaceutical preparations dating to the 18th and 20th century by liquid and gas chromatography with UV-spectrometric or mass spectrometric detection. The analytical approach was chosen with regards to the age and pharmaceutical forms of the analyzed historical remain. The authenticity of the sample was verified by identifying the active ingredients, their possible degradation products and other excipients by tandem mass spectrometry. The fragmentation of some analytes was also studied by tandem mass spectrometry. The stability of historical pharmaceutical preparations from the 20th century was assessed on the basis of a decrease in the concentration of active substances compared to the content declared by the manufacturer or, in case of historical pharmaceutical remains from the 18th century, on the basis of active substance concentrations determined in the historical residue and current reference material. A multi-analytical approach combining five analytical methods, the results of which complement each other, was used to analyze the historical remains of ointments. While the active substances identified in ipecacuanha were found to be partially degraded, they were completely degraded in senna...
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Monitoring kyseliny askorbové v ovocných nápojích
Chytilová, Barbora
The thesis deals with monitoring of ascorbic acid and other substances in selected fruit drinks. The theoretical part begins with a summary of knowledge about the occurrence and importance of ascorbic acid and their physiological effects. Furthermore, the content of vitamin C in individual fruits is compared. The following part deals with the division of soft drinks and raw materials, used for the production of soft fruit drinks. Part of the thesis is focused on the technology of fruit juice production obtained by direct pressing of fruit material and technology of fruit drinks production from fruit concentrates. The practical part is focused on determination of vitamin C concentration as well as vitamins of group B (B1, B2, B3, B5, B6) and organic acids (citramic acid, citric acid, malic acid, pyruvic acid and succinic acid) in samples of direct fruit juices and juice from concentrate. Mass spectrometer-coupled high-performance liquid chromatography (HPLC-MS) was used to detect vitamin C and other substances.
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Monitoring biologicky aktivních látek v kávě
Rokosová, Kateřina
The topic of this Master thesis is The Monitoring of Biologically Active Substances of Coffee. The technological production of coffee beans from harvesting the crops to the final packaging is described in the theoretical part, together with the chemical composition of both green and roasted coffee beans. The next part sums up the current knowledge of biologically active substances that can be found in coffee and their effect on human health. The main focus has been put on phenolic compounds and their antioxidant properties. The last chapter of the theoretical part tells of modern ways which are used to define phenolic compounds. The practical part of the thesis identifies phenolic compounds in coffee beans of two kinds, Coffea arabica and Coffea canephora, roasted at different temperatures and in the range from very raw beans to over-roasted ones. A highly efficient High Performance Liquid Chromatography in connection with Mass Spectrometry has been used to detect the most significant phenolic compounds.
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Stability of selected mycotoxins in beer
Štáblová, Taťána ; Benešová, Karolína (referee) ; Běláková, Sylvie (advisor)
Mycotoxins are secondary metabolites of moulds, which attack cereals, for example barley, from which mycotoxins then get to beer. This submitted work is focused on ochratoxin A, deoxynivalenol and zearalenone, which can occur in beer. The first part of this master’s thesis consists of literary research, which describes mycotoxins in general, points out their occurrence, prevention of their formation and delivers information about their physical and chemical properties and toxicity. Furthermore, the research contains basis of malt and beer technology, the occurrence of mycotoxins in beer and raw materials for its production. The research describes changes in concentration of mycotoxins across malt and beer production. The next part deals with possibilities of determination of mycotoxins in barley, malt and beer, compares individual methods of their determination and points out many difficulties of some analyses. The experimental part of this work pursues determination of ochratoxin A, deoxynivalenol and zearalenone in different types of beer with the help of UPLC-FLR, HPLC-MS and ELISA. Instrumental techniques are validated and gathered results are compared with the results in literature. The goal of this master’s thesis is to assess the stability of ochratoxin A and deoxynivalenol in beer over time. The gained results show that there are changes in the concentration of ochratoxin A over time, nevertheless those changes show no pattern. Overall, there was a decrease in concentration in 47 % of the samples and an increase in 28 % of them. In the rest of the samples the concentration did not change. The concentration of deoxynivalenol does not change over time. One of the other goals of this thesis is monitoring of selected mycotoxins in beer. The average concentration of ochratoxin A in the samples was 39 ng/l and deoxynivalenol 9,9 g/l. Zearalenone did not occur in any of the samples when determined by liquid chromatography. All results agree with literature. Next, the thesis compares different analytical methods for determination of ochratoxin A, deoxynivalenol and zearalenone. The screening method ELISA is compared to UPLC-FLR and HPLC-MS. The determination of ochratoxin A by ELISA has shown to be time consuming, nevertheless the results responded to instrumental technique. ELISA overestimated the results of determination of deoxynivalenol in beer by 363–697 % and with zearalenone there were found false positive results.
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The Preparation and the Characterization of the Cationic Liposomes Carrying New Immunoadjuvant.
Houšť, Jiří ; Nesměrák, Karel (advisor) ; Kozlík, Petr (referee)
The aim of this diploma thesis was preparation, characterization and determination of encapsulation efficiency of the cationic liposomes composed of dimethyldioctadecylammonium bromide (DDAB) and cholesterol carrying new drug MT05 with an immunoadjuvant effect. The influence of the temperature of sonication bath and the influence of the volume of liposomal suspension on the average size of liposomes and their polydispersity index was monitored. The most effective liposome preparation by sonication bath was at temperature of 60 řC. The volume of liposomes undergoing sonication did not influence the resulting values of the average size of liposomes and their polydispersity index. The time of sonication time was 6 hours and could be shortened by using sonication bath with higher output. The determination of encapsulation efficiency was carried out in three separated experiments by HPLC-MS/MS. The encapsulation efficiency of the cationic liposomes was 30.1 ± 8.5 % in the first experiment, 43 ± 25 % in the second, and 32 ± 25 % in the third. The amount of DDAB was determined only in the liposomes prepared in the third experiment. The amount of DDAB in the purified liposomes was 78.9 ± 3.7 % in the first replicate, 65.4 ± 1.8 % in the second and 53.8 ± 1.4 % in the third. The actual molar ratio of MT05...
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Determination of niacin and its metabolites by HPLC-MS
Pultarová, Kamila ; Čabala, Radomír (advisor) ; Staňková, Barbora (referee)
Nicotinic acid (NA) is a hypolipidemic agent with pleiotropic effects on plasma lipoproteins. Its medicamentous form with delayed secretion leads to pyrimidine metabolites, which make increased risk of hepatotoxicity and should be monitored. The aim of the presented study was to introduce HPLC-MS method for the determination of NA, nicotinamide (NAM), nicotinuric acid (NUA), 1-methyl-nicotiamide (MNA), nicotinamid-N-oxide (NNO), 1-methyl-2-pyridon-5-carboxamide (2-Pyr) and 1-methyl- 4-pyridon-5-carboxamide (4-Pyr) in blood plasma useful for the monitoring of hypolipidemic therapy. We have compared calibration dependences of individual metabolites using two columns - Hypercarb (grapfite carbon) and Hypersil Silica (silicagel). Both columns revealed linear calibration dependences for all mentioned analytes except MNA in the concentration range 10-2000 ng/ml for chemical standards; calibration dependence in human blood plasma measured with the column Hypersil Silica was linear in the range 20-4000 ng/ml for all tested analytes. Correlation coefficient varied between the value 0,9400 and 0,9997. Analysis time was 15 min with the column Hypercarb and 27 min with Hypersil Silica. Biological samples were extracted using solid phase with sulphonyl group. Reproducibility of the results of biological samples...
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