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Application of immunochemical and LC/MS/MS techniques in the detectionof sulfonamide residues in livestockWong, Chun-kit, Jack., 蔣蔚宜. January 2006 (has links)
published_or_final_version / Medical Sciences / Master / Master of Medical Sciences
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Aspects of the metabolism of aromatic amines particularly sulphanomide drugsBridges, James Wilfrid January 1963 (has links)
The work described in this thesis is in three parts:. Part I deals with the metabolism of 5-p-aminobenzene-sulphonamide- 3-methylisothiazole (sulphasomizole), 5-amino-3--methylisothiazole, sulphanilamide, and some of the acetyl derivatives. A marked species difference has been found in the metabolism of sulphasomizole.
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Procarbazone-sodium effect on rotational crops and its dissipationAl-Sayagh, Khalid Faraj 14 December 1998 (has links)
Graduation date: 1999
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Reductive cleavage of N-substituted benzenesulfonamides and p-sulfamylbenzoic acidDavenport, Robert E. 01 January 1975 (has links)
The objective of the present work was to study further the effect of varying substituents on the nitrogen atom and on the ring of sulfonamides in the Birch reduction of aromatic sulfonamides, especially with respect to the amount of thiol formed, in the hope that information concerning the initial cleavage step might be discerned.
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Validação de metodologias para determinação de antimicrobianos em pescado por cromatografia líquida de alta eficiênciaSANTOS, Paloma do Nascimento dos 16 March 2009 (has links)
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Previous issue date: 2009-03-16 / Antimicrobials are widely used in veterinary medicine and these residues may remain in food of animal origin, above values considered safe, creating risks to human health and the environment. This work was validate methodologies for determination of sulfonamides in shrimp and florfenicol in shrimp and tilapia using High Performance Liquid Chromatography as analytical technique. The determination of sulphonamides in shrimp was accomplished using a C18 column and mobile phase composed of ACN:water (25:75) in gradient method. The sample was extracted using acetonitrile and filtrade on anhydrous sodium sulphate. After evaporation, was a clean up in ion exchange cartridges (500 mg/6mL) followed by evaporation of the solvent to dryness and subsequent ressuspension in acetic acid 0.5% for filtration and analysis by HPLC. The determination of florfenicol in shrimp and tilapia was also used a C18 column and isocratic method. The extraction was performed with ethyl acetate, followed by centrifugation and extraction of fat phase with hexane. After a second centrifugation, the upper phase was discarded and the aqueous phase filtered and taken for analysis by HPLC. The methodology for determination of sulfonamides was shown to be selective and linear for a range of work from 100 to 1000μg L-1. The LOD and LOQ (μg L-1) was 6.35 and 20.19 to sulfathiazole, 2.44 and 7.76 for sulfamethazine, 0.58 and 1.83 for sulfamethoxazole, 1.49 and 4.75 for sulfadimethoxine and 3.41 and 10.85 for sulfaquinoxaline. The methodology for determining florfenicol shown to be selective and linear for a range of work from 0.1 to 3.0 mg L-1 and the LOD and LOQ (mg L-1) to matrix shrimp were 2.97 and 15.01 mg kg-1 respectively. For tilapia matrix the lowest concentrations detected and quantified by method, were 3.64 and 18.54 mg kg-1 respectively. All results are in accordance with applicable law for the determination of antimicrobial by HPLC. / Antimicrobianos são largamente empregados na medicina veterinária e resíduos destes podem permanecer nos alimentos de origem animal, acima de valores considerados seguros, gerando riscos para a saúde humana e para o meio ambiente. O objetivo deste trabalho foi validar metodologias para determinação de sulfonamidas em camarão e florfenicol em camarão e tilápia utilizando a Cromatografia Líquida de Alta Eficiência como técnica analítica. A determinação de sulfonamidas em camarão foi realizada usando uma coluna C18 e fase móvel composta por ACN;Água (25:75) em método gradiente. A amostra foi extraída utilizando acetonitrila e filtrada em sulfato de sódio anidro. Após a evaporação, foi feito um clean up em cartuchos de troca iônica (500 mg/6mL) seguida de evaporação do solvente até secura e posterior ressuspensão ácido acético 0,5% para filtração e análise por CLAE. Para a determinação de lorfenicol em camarão e tilápia também foi utilizada uma coluna C18 e méodo isocrático. A extração foi realizada com acetato de etila, seguido de centrifugação e extração da gordura com hexano. Após uma segunda centrifugação, a fase superior foi descartada e a fase aquosa filtrada e levada para análise por CLAE. A metodologia para determinação de sulfonamidas mostrou-se seletivo e linear para uma faixa de trabalho de 100 a 1000μg L-1 a apresentou limites de detecção e quantificação para a sulfatiazol de 6,35 e 20,19, para a sulfametazina 2,44 e 7,76, para a sulfametoxazol 0,58 e 1,83, para a sulfadimetoxina 1,49 e 4,75 e para a ulfaquinoxalina 3,41 e 10,85 μg kg-1 respectivamente. A metodologia para determinação de florfenicol mostrou-se seletivo e linear para uma faixa de trabalho de 0,1 a 3,0 mg L-1 e o limite de detecção e quantificação do método para a matriz camarão foram 2,97 e 15,01 μg kg-1 respectivamente. Para a matriz tilápia as menores concentrações detectadas e quantificadas pelo método foram de 3,64 e 18,54 μg kg-1 respectivamente. Os métodos validados mostraram-se adequados para a determinação dos antimicrobianos citados e todos os resultados encontram-se em conformidade com a legislação vigente.
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Synthetic, spectroscopic and computational studies of aromatic compounds : structure, fragmentation and novel dimerisation of indoles under electrospray conditions, and innovative nitrogen to carbon rearrangement of orthogonally protected sulphonamides and related compoundsSaidykhan, A. January 2015 (has links)
The complementary value of vibrational spectroscopy and mass spectrometry in obtaining structural information on a range of tricyclic indoles with various ring patterns has been investigated, focusing particularly on whether these heterocycles with a functional group containing oxygen in the third ring should be described as ketoindoles or hydroxindolenines. Parallels between certain fragmentations of ionised indoles and electrophilic substitution in solution have been identified. A mechanistically interesting and analytically useful interesting dimerisation, leading to the formation of [2M-H]+ ions, has been discovered in the positive ion electrospray mass spectra of 3-alkylindoles. This dimerisation, which occurs in the nebuliser of the instrument, offers a potential new route to bisindoles under milder conditions than those employed in classical solution chemistry. Facile formation of C=N bonds by condensation of C=O and H2N has been shown to provide a means of preparing protonated imines and protonated quinoxalines from mixtures of the requisite (di)carbonyl compounds and (di)amines, thus further illustrating how organic synthesis is possible in the droplets in the nebuliser of the instrument. Possible metal catalysed coupling reaction routes to bisindoles have been explored. Acyl transfer reactions from nitrogen to carbon have been investigated in 1-acyl-2-methylindoles and orthogonally protected sulphonamides. These processes have been shown to be intermolecular and intramolecular, respectively. The latter rearrangement, which may be prevented when necessary by choosing the nitrophenylsulphonamide protecting group, offers a route to acyl, carboalkoxy and carboaryloxy aromatic compounds, some of which are difficult to prepare.
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Problematika stanovení reziduí léčiv v odpadních vodách / Problems of Drug Residues Determination in Waste WatersLisá, Hana January 2011 (has links)
The PhD thesis deals with determination of sulfonamides and tetracyclines in waste waters. Sulphonamides and tetracyclines are widely used in human and veterinary medicine. They are biologically active compounds and block biological processes in waste water treatment plants. These substances can influence microorganisms in the environment. Sulphonamides and tetracyclines induce resistance in low concentrations. These substances penetrate into the environment from industrial production, use in households, hospitals, veterinary clinics and fish farms. Tetracyclines and sulphonamides were determined in waste water from waste water treatment plants in Brno. Optimalization of extraction of these compounds was performed by solid phase extraction. Sulphonamides and tetracyclines were determined by liquid chromatography coupled with diode array detector or coupled with mass spectrometry. Optimalized method was used for determination tetracyclines and sulphonamides in waste water from waste water treatment plants in Brno in years 2007 – 2010.
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Synthetic, Spectroscopic and Computational Studies of Aromatic Compounds. Structure, Fragmentation and Novel Dimerisation of Indoles under Electrospray Conditions, and Innovative Nitrogen to Carbon Rearrangement of Orthogonally Protected Sulphonamides and Related CompoundsSaidykhan, Amie January 2015 (has links)
The complementary value of vibrational spectroscopy and mass spectrometry in obtaining structural information on a range of tricyclic indoles with various ring patterns has been investigated, focusing particularly on whether these heterocycles with a functional group containing oxygen in the third ring should be described as ketoindoles or hydroxindolenines. Parallels between certain fragmentations of ionised indoles and electrophilic substitution in solution have been identified.
A mechanistically interesting and analytically useful interesting dimerisation, leading to the formation of [2M-H]+ ions, has been discovered in the positive ion electrospray mass spectra of 3-alkylindoles. This dimerisation, which occurs in the nebuliser of the instrument, offers a potential new route to bisindoles under milder conditions than those employed in classical solution chemistry. Facile formation of C=N bonds by condensation of C=O and H2N has been shown to provide a means of preparing protonated imines and protonated quinoxalines from mixtures of the requisite (di)carbonyl compounds and (di)amines, thus further illustrating how organic synthesis is possible in the droplets in the nebuliser of the instrument.
Possible metal catalysed coupling reaction routes to bisindoles have been explored. Acyl transfer reactions from nitrogen to carbon have been investigated in 1-acyl-2-methylindoles and orthogonally protected sulphonamides. These processes have been shown to be intermolecular and intramolecular, respectively. The latter rearrangement, which may be prevented when necessary by choosing the nitrophenylsulphonamide protecting group, offers a route to acyl, carboalkoxy and carboaryloxy aromatic compounds, some of which are difficult to prepare.
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Estudio de la presencia y comportamiento de las sulfamidas en el medio ambienteGarcía Galán, María Jesús 31 January 2013 (has links)
Durante la última década se han publicado un gran número de estudios de investigación sobre la ubicuidad de diferentes contaminantes orgánicos en todo tipo de matrices ambientales, principalmente en agua. Entre éstos, la presencia medioambiental de fármacos y en concreto de antibióticos ha sido investigada con especial interés, debido a sus altas tasas de consumo y elevada actividad biológica (promoción de resistencia bacteriana). A este deterioro de la calidad de los recursos hídricos se une además el problema de su escasez, sobre todo en las cuencas mediterráneas, de modo que la reutilización del agua se hace imprescindible. Sin embargo, la falta de eficacia de los sistemas convencionales de tratamiento de aguas residuales para eliminar estos contaminantes orgánicos pone de manifiesto su entrada continuada en las aguas superficiales receptoras mediante los efluentes de las depuradoras, y el riesgo que supondría esta reutilización. Así pues, queda patente la necesidad de disponer de información nueva y valiosa sobre la presencia medioambiental de las sulfamidas, familia de antibióticos de alto consumo y cuya presencia medioambiental tiene origen en un uso principalmente veterinario y agrícola, (sulfametazina, sulfadimetoxina), pero también humano (sulfametoxazol, sulfapiridina). Para ello, es necesario el desarrollo de diversas herramientas analíticas avanzadas que nos permitieran la determinación de esta familia de antibióticos en diferentes matrices de agua ambiental, así como en fango de depuradora y suelo agrícola. Con las diferentes metodologías analíticas se pretende evaluar la presencia y persistencia de estos antibióticos y de sus metabolitos mayoritarios en los diferentes ecosistemas acuáticos, evaluando la eficacia de las técnicas de tratamiento de aguas residuales convencionales aplicadas en la actualidad en diferentes EDARs, y también de varias alternativas como los bioreactores de membrana o los bioreactores de lecho fijo (MBR o FBBR, respectivamente). Asimismo, estudiando su biodegradabilidad y persistencia medioambiental, es posible conocer en mayor profundidad la naturaleza y comportamiento de estos compuestos.
Considerando todo lo anterior, durante el desarrollo de esta Tesis nos hemos marcado como principal objetivo el desarrollo y aplicación de nuevas metodologías analíticas basadas en la cromatografía de líquidos acoplada a la espectrometría de masas para la determinación de sulfamidas y sus metabolitos acetilados en aguas (residuales, superficiales, subterráneas) y matrices sólidas (fangos de depuradora y suelos agrícolas). Durante el análisis de aguas residuales, se evaluó también la eliminación de estos compuestos durante el tratamiento en las diferentes depuradoras, comparando la eficacia de diferentes tipos de tratamiento y su impacto en las zonas de vertido, comprendiendo así el destino de estos antibióticos en todo el ciclo del agua. Posteriormente, estudiamos la biodegradabilidad de diferentes sulfamidas mediante el tratamiento con hongos en medio líquido y sólido, y se llevó a cabo la identificación de los productos de transformación derivados mediante cromatografía de líquidos de ultra-alta resolución-espectrometría de masas en tándem con un sistema híbrido cuadrupolo tiempo de vuelo (UHPLC-QqTOF-MS/MS). También realizamos un estudio de destino de las sulfamidas, evaluando la fotodegradación de algunas de ellas y sus metabolitos acetilados en diferentes matrices acuosas, considerando también la aparición e identificación de los productos de fototransformación que se generan durante su fotólisis mediante UHPLC-QqTOF-MS/MS. Por último, mencionar que con los datos de presencia medioambiental obtenidos se llevó a cabo la evaluación del impacto medioambiental de las sulfamidas detectadas en los diferentes tipos de agua estudiados, estimando los coeficientes de riesgo asociados siguiendo las directrices marcadas por la Agencia Europea del Medicamento (EMEA). / Sulfonamides (SAs) are one of the most widely used antibiotics in human and especially in animal husbandry. So far, concern regarding the environmental presence of sulfonamides and other species of antibiotics has focused mainly on the potential spread of antimicrobial resistance. However, their biological activity and high resistance to biodegradation may lead to long residence times in both water and soil matrices. Long-term ecological risks and unpredicted effects can result from unintentional exposure of different organisms and even human health could be negatively affected. In this context, this PhD thesis aimed to study the environmental occurrence of the most relevant sulfonamides in all types of waters, sewage sludge and agricultural soils. In order to fully understand the fate and effects of this family of antimicrobials in the environment, further research on their resiliance and biodegradability has been carried out. The need of developing new advanced analytical methodologies, fast, robust and with high sensitivity for the analysis of sulfonamides and their acetylated metabolites at environmental levels was the first and one of the main objectives of this PhD Thesis. These analytical methodologies were succesfully applied for the analysis of real samples in different monitoring studies in wastewater treatment plants, rivers and aquifers. Sulfonamides and their acetylated metabolites were ubiquitous in all the water samples studied, with levels ranging from the low pg L-1 to μg L-1 (mainly in wastewater influents, but also in some surface water samples from the Llobregat River). Maximum levels detected in sewage sludge were up to 139.2 ng g-1 (sulfamethazine). The last part of the PhD focused on the biodegradability and behaviour of the sulfonamides in the environment. The efficiency of conventional wastewater treatments, usually based on activated sludge (CAS), was evaluated and removal rates were estimated for the different sulfonamides studied. The ability of white rot fungi Trametes versicolor to degrade sulfamethazine was also studied, as well as the photodegration kynetics of sulfapyridine, sulfamethazine and their respective acetylated metabolites in wastewater effluents and HPLC water under simulated irradiation.
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