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Bisphenol A in water ecosystem
Nohelová, Gabriela ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
This diploma thesis deals with Bisphenol A, especially with its impact on the aquatic ecosystem. Information about its properties, production and current use are summarized here. Its harmful impact on the environment, especially on the aquatic ecosystem and the human body is characterized. Also the methods of its degradation within the aquatic environment have been described. A summary of the options of a determination of Bisphenol A in water samples is incorporated and the method of gas chromatography with mass spectrometry (GC/TOF MS) and comprehensive two-dimensional gas chromatography with mass spectrometry (GCxGC/TOF-MS) is compared in the experimental part. Analytical determination precedes the isolation of the analyte from the water samples by solid phase extraction (SPE) using SupelcleanTM ENVITM - 18 and derivatization using the silylation reagent, N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). The result of this work is the analysis of a series of real samples from wastewater treatment plants Brno Modřice and Luhačovice by a two-dimensional gas chromatography with mass spectrometry (GCxGC/TOF-MS).
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Non-target screening of organic pollutants in waters and sediments
Hamalčíková, Veronika ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
This master thesis deals with the potential influence of the waste dump Hrádek u Pacova and the wastewater treatment plant Brno – Modřice on surroundings using the optimized non-target screening method of organic pollutants in water and sediments. The experimental part is focused on the identification of organic compounds in samples of ground water from monitoring wells, the surface water from stream and pond and in sediment samples collected from streams in the vicinity of municipal waste dump. Organic compounds were also identified in water and sediment samples from the river Svratka near the municipal waste water treatment plant Modřice. The sequential liquid – liquid extraction was used for the isolation of organic compounds in water samples. Organic compounds in sediment samples were isolated by pressurized solvent extraction (PSE) with subsequent fractionation of the extract using column chromatography. Final analysis determination was performed using comprehensive orthogonal two-dimensional gas chromatography with mass spectrometric detection (GCxGC-TOF MS).
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The use of GC/MS for the analysis of drugs
Sýkora, Richard ; Opatřilová, Radka (referee) ; Vávrová, Milada (advisor)
This diploma thesis is based on the current issue of the presence of pharmaceuticals in various components of the environment. Concerning the contamination by residues of pharmaceuticals the most affected environment is the aquatic environment where these substances leaks especially from wastewater treatment plants, which eliminate them during the cleaning process only partially. This work is focused on the selected group of pharmaceuticals, non-steroidal anti-inflammatory drugs (salicylic acid, ibuprofen, caffeine, naproxen, ketoprofen, diclofenac) in waste water. For analysis purposes two types of sampling were used and compared: the conventional spot sampling of wastewater and the sampling using passive samplers POCIS. The sampling took place at the inflow and outflow of the wastewater treatment plant in Brno Modřice. The solid phase extraction (SPE) using Oasis HLB columns was used as the extraction method. Extracted sample was derivatized then. Derivatization agents were: MSTFA (N-methyl-N-(trimethylsilyl)trifluoroacetamid) and BSTFA (N, O-bis(trimethylsilyl) trifluoroacetamid). The final analysis was performed using gas chromatography with mass spectrometric detection Time-of-Flight (GC/TOF-MS).
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Passive sampling of polar organic pollutants from water
Vítková, Libuše ; Mravcová, Ludmila (referee) ; Čáslavský, Josef (advisor)
This thesis deals with the passive sampling of polar compounds from water using passive samplers POCIS (Polar Organic Chemical Integrative Sampler). These devices were exposed for 4 weeks in the waste water at the inflow of municipal waste water treatment plant in Brno – Modřice, and also at the outflow of the treated water. After exposition sequestered compounds were released by extraction with a mixture of methanol, toluene and dichlormethane. Extracts were analysed by liquid chromatography/mass spectrometry with electrospray ionization. Further, methylated and trimethylsilylated extracts were analysed by orthogonal comprehensive two-dimensional gas chromatography with mass spectrometric detection. Separated compounds were identified on the base of their retention and mass spectra.
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Aplication of gas chromatography for determination of drug residuals in waters
Lacina, Petr ; Stoupalová, Michaela (referee) ; Vávrová, Milada (advisor)
Diploma thesis is focused on the choose of methods and optimalisation analysis procedure of selected pharmaceuticals (salicylic acid, ibuprofene, naproxene, ketoprofene and diclofenac) in surface and waste water by using gas chromatography with mass spectrometer (GC-MS). Solid-phase extraction (SPE) with Oasis HLB cartridges was used as an extraction method in this analysis. Extraction is followed by derivatization and their optimalization of selected pharmaceuticals. Derivatization and its optimalization were performed by two silylation reagens N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). Different volumes of derivatization reagents, different temperatures and different times were used during the procedure. The best combination is then used for analysis of real samples. Real samples of waste water were collected in sewage treatment plants in Brno – Modřice and real samples of surface water were collected from several rivers and one pond in region Moravia. This thesis also presents and tests SPE methods for extraction and concentration selected sulfonamide residues (sulfamethazine, sulfamethoxazole, sulfapyridine and sulfathiazole) from the aquatic environment.
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Application of gas chromatography for determination of drug residuals
Sýkora, Richard ; Lisá, Hana (referee) ; Vávrová, Milada (advisor)
Analgesics are nowadays widely used group of drugs in human and also in veterinary medicine. Residuals of these drugs enter surface waters via discharges from the waste water treatment plants as the result of insufficient efficiency of their removal during cleaning process. In this bachelor thesis the possibilities of the analgesics residuals determination in waters using derivatization followed by gas chromatography with mass spectrometric detection were experimentally evaluated. Individual derivatization procedures were compared too. Several derivatization agents were tested and experimental parameters for selected analgesics were optimized (reaction time and temperature, amount of derivatizing agent). Further, several procedures of isolation of target compounds from water based on Solid Phase Extraction were verified. In all cases, gas chromatography with TOF-based mass spectrometric detection acts as final analytical method.
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Analysis of Fatty Acids in Diacylglyceroles and Triacylglyceroles of Body Fluids by Gass Chromatography
SCHNEEDORFEROVÁ, Ivana
Epinephrine is well known a stress hormone of mammals. The adipokinetic hormone (AKH) has the same function in insects. AKH is peptidic hormone; one species of insect possesses one or more types of AKH. Basically AKH is responsible for releasing of diacylglycerols (DGs) from fat body. Our experimental animal is common model organism, locust (Locusta migratoria). Those animal synthesizes three AKH types {--} AKH I, II and III. They differ in amino acid order in peptide, but having very similar influence on the organism. Recently used a routine sulfovaniline method for unsaturated fatty acids (FA) determination estimates only quantitatively the sum of double bounds in fatty acids. Our proposed method, perspective GC FID (Gas Chromatography with Flame Ionization Detector), is very revolutionary being able to determinate particular fatty acid species and also their relative ratio. Aim of this study is to find a proper sample preparation method for GC FID technique and to investigate the influence of particular AKH to the locust organism and to statistically prove the differences in AKH influences. A locust haemolymph was subjected by very usual sample extraction by Folch and a routine SPE (solid phase extraction) method. An easy and rapid derivatization by sodium methanolate was the next sample preparation step followed by GC FID measurement. Acquired data were computed by PCA (principal component analyses). We gained a well-arranged graphical output confirming our thesis that each AKH species has a different influence on FA composition in locust heamolymph; AKH II having the greatest influence.
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Analysis of organic acids by a novel procedure of extractive derivatization in human plasma and serum by GC/MS
JAHODOVÁ, Lucie
The theme of the bachelor{\crq}s thesis was ``The Analysis of Organic Acids by New Extractive Derivatization Process in Blood Plasma and Serum Using the GC/MS Technique{\crqq}. The objective of the thesis was to develop a method for fast determination of organic acids by a new process of extractive derivatization, to identify and determine organic acids in body fluids, to compare their abundance and to evaluate the possibility of implementation of this method in clinical diagnostics. Body fluids contain hundreds of organic acids, which co-create a clinical picture of a patient{\crq}s health condition. The current research focuses on implementation of methods providing for comprehensive, metabolism-based analysis of these metabolites important from the point of view of diagnostics. Nowadays, an analyst can select from a wide range of methods and several effective analytical and separation techniques for separation, determination and identification of organic acids in complex biological matrices. In the introductory, theoretical part of the bachelor{\crq}s thesis, the knowledge of properties of organic acids and possibilities of their determination are summarized. In the practical part, the method of fast determination of organic acids in body fluids by the GC/MS techniques was developed. By means of this technique, it is possible to analyze large quantities of organic acids in minimum volume of body fluid. Derivatization of a set of several tens of organic acids with ethyl chloroformate in aqueous medium was carried out. The reaction proceeds very fast and at laboratory temperature. The applicability of the developed method was verified through analysis of organic acids in biological samples. In samples of blood serum and plasma, tens of organic acids were identified by means of the above-mentioned method, retention data and EI mass spectra. Experiments performed for the purpose of this thesis proved that derivatization with chloroformates in aqueous medium is a relatively simple, fast and promising method for analysis of organic acids. Follow-up experimental research is necessary to make the methodology applicable in clinical diagnostics and to define advantages and limitations of this new methodological procedure.
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Chromatography methods for the determination of stable isotope traced metabolites and their apllication in the clinical research
ŽABOKRTSKÁ, Jana
In medical diagnostics substances labelled with radioactive or stable isotope tracers are used. At present stable isotope-traced substrates 13C or 2H are most commonly used for metabolism evaluation in pathologic situations. A modern approach is a combination of microdialysis method and an application of stable isotopes. In this study analytic methods for the determination of glucose and lactate in microdialysate are described. Due to used substances, labelled with stable isotope-tracers, these substances were determined by the method of gass chromatography with detection by mass spectrometry (GC-MS). The aim of the study was the development, determination of parameters, validation and optimalization of analytic methods oriented on measuring of isotope enrichment of molecules of chosen analytes. The isotope enrichment of glucose was determined after its derivatization by hydroxylamine hydrochloride and acetanhydride. A derivate aldonitril pentacetyl-D-glucose was determined. The method described in the study is the result of optimalization of time and temperature of derivatization of samples of microdialysates and chromatographic conditions. The obtained data were evaluated by the software Chemstation and statistics software SigmaStat. The precision was verified by the method of standard addition and was stated as 1,48%, the precision was determined by repeated measuring of a real sample {--} variation coefficient was 2,51%. Parameters of linear regression for concentrations 0,5 {--} 15 mmol/l were under given conditions with regression coefficient (R2) 0,9997 and the regression equation y = -0,0185 + 0,142x. Glucose for determination by gass chromatography is usually derivatized only by acetanhydride that however using capillary column CP-Sil 8 CB-MS (60 m x 0,32 mm) provides for interference in chromatographic recording {--} a double peak of likely formed anomers of pentacetyl-glucopyranose. For this reason it was necessary to make derivatization of aldehydic group of glucose first by hydroxylamin hydrochloride. The result method shows suitable parameters for using in analysis of microdialysate samples. Lactate was determined by derivatization by dimethoxypropane, propylamine and further by heptafluorobutyranhydride by formation of derivate of L-lactin-n-propylamidheptafluorobutyrate. Following parameters were determined {--} accuracy 3,25%, precision 3,15%, parameters of linear regression for concentrations wihtin 0,5 {--} 10 mmol/l were under given conditions R2 = 0,999 and the regression equation y = 0,215 + 1,039x. This relatively complicated derivatization method was taken over from an associated workshop at the University of Lausanne and its parameters were compared with a simpler method of derivatization by N-(butyl-dimethyl-silyl)-2,2,2-trifluoro-N-methyl-acetamide. The formed derivate di(tert-butyldimethylsilyl) lactate was determinated by the method GC-MS. The precision was 3,02%, accuracy 3,8%, parameters of linear regression R2 = 0,999, the regression equation y = -0,0809 + 0,792x. The presented methods were used in the pilot study of microdialyse of muscle and hepar of rats in various metabolic situations. At present the methods are used in clinical research on patients suffering from diabetes mellitus type I and have extended a spectrum of methods applied by the laboratory of the Clinic of Gerontology and Metabolism of the University Hospital of Hradec Králové.
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Effect of N eutrofication of wetland soils on organic N content and quality
ŠEDA, Martin
This study deals with an effect of fertilization on amount and quality of free amino acids in soil from wet meadows affected by nutrient loading. Free amino acids were analysed in the soil from the field experiment situated at wet meadows, where an increased nutrient input is simulated (fertilizer NPK). The experiment was established on two sites with different types of soil {--} Záblatí with organic soil and Hamr with mineral soil, both areas in the South Bohemia region. The soil was repeatedly sampled for more than two years and year. One part of this study is focused on testing of ninhydrine-method and HPLC-method for measuring free amino acids and efficiency of different extractants.
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