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Synthesis of fluorinated heterocyclic compounds and study of their interaction with DNAZeinali, Fatemeh January 2017 (has links)
Over fifty structurally diverse, novel fluorinated heteroarenes, have been successfully synthesised by SNAr reaction of a range of fluorinated arenes including pentafluoropyridine, hexafluorobenzene, and methyl pentafluorobenzoate by introduction of a range of groups such as imidazole, triazole, benzimidazole, benzotriazole, and carbazole. Different water solubilising side chains were introduced to some of the successfully synthesised fluorinated heteroarenes to improve water solubility and potential biological activity. X-ray crystal structures of over 10 compounds were obtained including those of two macrocyclic compounds containing 21- and 24-membered rings. The synthesised compounds have been characterized by elemental analysis, IR, 1H and 19F spectroscopy and high resolution mass spectrometry. These compounds have been screened for their biological activities and possible interaction with DNA by methods including UV-visible spectroscopy, fluorescence spectroscopy, co-crystallization for X-ray diffraction analysis, and antimicrobial activity. A number of the fluoroaryl benzimidazole derivatives have been tested against K-562 and MCF-7 cell lines and G361 and HOS cell lines. From the all tested compounds three tethered fluoroaryl benzimidazole derivatives demonstrated micromolar inhibition against K-562 and MCF-7 cell lines. These compounds, in addition to 1-tetrafluoropyrid-4-yl-2-tetrafluoropyrid-4-ylsulfanyl-1H-benzimidazole, also demonstrated micromolar inhibition against G361 and HOS cell lines. Two of the compounds were found to activate caspases leading to apoptosis.
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Liberação de compostos orgânicos das resinas KaloreTM e FiltekTM Silorane em função da fonte de luz polimerizadora, dos meios de imersão e do pH / Release of organic resins KaloreTM and FiltekTM Silorane according to the source of curing light, the immersion solution and pHKarina Alessandra Michelão Grecca Pieroni 13 June 2013 (has links)
Compostos orgânicos podem ser liberados dos materiais resinosos, mesmo após sua polimerização, como resultado da presença de monômeros residuais e do processo de degradação do próprio material, podendo ocasionar efeitos citotóxicos, genotóxicos e alergênicos. O objetivo do presente estudo, in vitro, foi avaliar a liberação de compostos orgânicos de dois materiais resinosos, recentemente lançados no mercado, que apresentam inovações em suas formulações (resinas Kalore TM - GC FUJI e FiltekTM Silorane - 3M ESPE), variando a fonte de luz polimerizadora (halógena ou LED), a solução de imersão (água ou saliva artificial) e o pH da solução de imersão (7 ou 4,5). Foram confeccionados 56 corpos de prova da resina Kalore TM e 56 da resina FiltekTM Silorane, sendo 28 polimerizados com luz halógena e 28 com luz LED. Após aleatorização, 7 corpos de prova de cada resina foram armazenados em água com pH neutro, 7 em água com pH ácido, 7 em saliva com pH neutro e 7 em saliva com pH ácido. A leitura dos espectros das soluções foi realizada por meio da espectroscopia de fluorescência após 1, 3, 24, 48, 72, 168, 216, 312, 432, 504 e 672 horas. Após 672 horas, ainda verificou-se a liberação de compostos orgânicos das resinas KaloreTM e FiltekTM Silorane em todas as condições avaliadas. A liberação de compostos orgânicos foi menor nos grupos experimentais polimerizados pela luz LED. A quantidade de compostos orgânicos liberados foi menor nas amostras imersas em saliva. A resina KaloreTM liberou uma quantidade maior de compostos orgânicos em pH neutro, independente do meio de imersão. A resina FiltekTMSilorane liberou uma quantidade maior de compostos orgânicos em pH ácido, quando imersas em água, e uma maior quantidade de compostos orgânicos em pH neutro, quando imersas em saliva. A resina FiltekTMSilorane liberou mais de um componente orgânico. A espectrometria de fluorescência permitiu avaliar a liberação de compostos orgânicos das resinas KaloreTM e FiltekTM Silorane. / Organic compounds may be released from the resin materials, even after polymerization, as a result of the presence of residual monomers and degradation of the material itself, which may cause cytotoxic, genotoxic and allergenics effects. The purpose of this study, in vitro, was to evaluate the release of organic compounds from two resin materials, recently launched on the market, that present innovations in their formulations (resins KaloreTM - GC FUJI and FiltekTM Silorane - 3M ESPE), varying the source curing light (LED or halogen), the immersion solution (water or artificial saliva) and the pH of the immersion solution (7 or 4.5). Were prepared 56 specimens resin KaloreTM and 56 resin FiltekTM Silorane, 28 polymerized with halogen light and 28 with LED light. After randomization, 7 samples of each resin were immersed in water at neutral pH, 7 in water at acid pH, 7 in the saliva at a neutral pH, and 7 in the saliva at acid pH. The reading of the spectra of the solutions was performed by fluorescence spectroscopy at 1, 3, 24, 48, 72, 168, 216, 312, 432, 504 and 672 hours. After 672 hours, there was still release of organic resins KaloreTM and FiltekTM Silorane under all conditions evaluated. The release of organic compounds was lower in the experimental groups polymerized by LED light. The amount of organic compounds released was lower in samples immersed in saliva. The resin KaloreTM released more organic compounds at neutral pH in both immersion media. The resin FiltekTMSilorane immersed in water released more organic compounds at acid pH, but when the resin was immersed in saliva the release of organic compounds was higher at neutral pH. The resin FiltekTMSilorane released more that one organic component. The fluorescence spectrometry allowed us to evaluate the release of organic compounds resins KaloreTM and FiltekTMSilorane.
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Fluorescencia de uranio induzida por laser como um metodo analiticoKRUTMAN, IANAI 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:25:21Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:05Z (GMT). No. of bitstreams: 1
02239.pdf: 1159186 bytes, checksum: 267eeba1401f50b43f5e2b8ef689ffbf (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Utilização da espectroscopia de fluorescência para mensuramento de moléculas autofluorescentes em indivíduos diabéticos / Use of fluorescence spectroscopy to measure molecular autofluorescence in diabetic subjectsGOMES, CINTHIA Z. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:21Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:31Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Fluorescencia de uranio induzida por laser como um metodo analiticoKRUTMAN, IANAI 09 October 2014 (has links)
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02239.pdf: 1159186 bytes, checksum: 267eeba1401f50b43f5e2b8ef689ffbf (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Utilização da espectroscopia de fluorescência para mensuramento de moléculas autofluorescentes em indivíduos diabéticos / Use of fluorescence spectroscopy to measure molecular autofluorescence in diabetic subjectsGOMES, CINTHIA Z. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:21Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:31Z (GMT). No. of bitstreams: 0 / Diabetes Mellitus (DM) é uma síndrome metabólica complexa, causada pela secreção diminuída ou ausente de insulina pelas células beta pancreáticas, levando a hiperglicemia. A hiperglicemia promove a glicação de proteínas e, conseqüentemente, o aparecimento de produtos finais da glicação avançada (AGEs). Atualmente, os pacientes diabéticos são monitorados pela determinação dos níveis de glicemia e hemoglobina glicada (HbA1c). As complicações geradas pela hiperglicemia podem ser divididas em micro e macrovasculares, representadas por retinopatias, nefropatias, neuropatias e doenças cardiovasculares. A albumina (HSA) é a proteína sérica mais abundante no organismo humano e está sujeita à glicação. A protoporfirina XI (PpIX) é a molécula precursora da síntese do heme, componente estrutural da hemoglobina. Ensaios in vitro e em animais indicaram que a hiperglicemia promove uma diminuição de sua concentração em eritrócitos. A espectroscopia de fluorescência é uma técnica bastante utilizada na área biomédica. A autofluorescência corresponde à fluorescência intrínseca presente em algumas moléculas, estando esta associada à estrutura das mesmas. O objetivo deste trabalho foi utilizar a técnica de espectroscopia de fluorescência para mensurar os níveis de autofluorescência da PpIX eritrocitária e AGE-HSA em pacientes diabéticos e indivíduos saudáveis e compará-los com os níveis de glicemia e HbA1c. Este estudo foi realizado com 151 indivíduos (58 controles e 93 diabéticos). Os dados epidemiológicos de pacientes e controles foram obtidos nos prontuários médicos. Para os indivíduos controle, os valores de glicemia foram adquiridos dos prontuários médicos e os níveis de Hb1Ac obtidos pela utilização de kits comerciais. A determinação da autofluorescência da PpIX foi realizada com excitação de 405 nm e emissão de 632 nm. Para a determinação do AGE-HSA foi realizada excitação de 370 nm e emissão de 455 nm. Aproximadamente 50% dos diabéticos apresentaram lesões micro ou macrovasculares decorrentes da hiperglicemia. Não foram observadas diferenças significativas nos valores de intensidade de emissão de PpIX entre os grupos estudados (P=0,89). Na análise do AGE-HSA observou-se diferenças significativas dos valores de intensidade de emissão entre os dois grupos, sendo este valor 1,45 vezes maior para o grupo de indivíduos diabéticos (P<0,0001). Os pacientes com complicações diabéticas apresentavam intensidade de emissão de fluorescência 1,19 vezes maior que os indivíduos sem complicações decorrentes da doença (P= 0,01), mesmo não havendo diferenças significativas nos valores de HbA1c entre os dois grupos. Concluímos que a espectroscopia de fluorescência foi uma técnica eficaz na identificação da autofluorescência da PpIX e do AGE-HSA. A PpIX não foi um biomarcador eficiente para o acompanhamento do DM. A determinação dos níveis de autofluorescência do AGE-HSA foi eficiente para a discriminação entre os grupos e para o monitoramento da progressão da doença, podendo ser mais eficiente que a dosagem de HbA1c. A espectroscopia de fluorescência é uma técnica simples, rápida e de baixo custo para o acompanhamento de indivíduos diabéticos. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Aplicação de metodos quimiometricos de calibração de segunda ordem e transferencia de calibração na determinação simultanea de misturas de farmacos utilizando espectroscopia de fluorescencia molecular em fase solida / Aplication of chemometric methods of second order calibration and transfer of calibration for simultaneous determination of pharmaceutical mixture using solid-phase molecular fluorescenceAlves, Julio Cesar Laurentino, 1978- 13 August 2018 (has links)
Orientador: Ronei Jesus Poppi / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-13T00:09:21Z (GMT). No. of bitstreams: 1
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Previous issue date: 2009 / Resumo: Neste trabalho foi desenvolvida uma metodologia para determinação simultânea da mistura farmacêutica de ácido acetilsalicílico (AAS), paracetamol e cafeína, através de fluorescência de excitação-emissão em fase sólida. Esta metodologia é aplicável mesmo na presença de interferentes e com sobreposição espectral dos componentes da mistura, sem prejuízo da boa reprodutibilidade e exatidão, obtendo erros menores que 5%. Para tanto utilizou-se os métodos quimiométricos de calibração de segunda ordem PARAFAC e UPLS, além do método de calibração de primeira ordem PLS2. Vantagens observadas em relação aos métodos de referência como o menor custo, a não necessidade de longo preparo da amostra e análise simples e rápida, além de não haver geração de resíduos, tornam esse método bastante atrativo, permitindo a determinação simultânea dos compostos na mistura estudada. Ainda, a fim de propor uma solução para o problema que foi observado durante o desenvolvimento dos modelos, relativo à mudança da matriz da amostra, utilizou-se transferência de calibração. Nesse estudo, a padronização de espectros através do método da Padronização Direta por Partes (PDS) foi aplicada a modelos UPLS construídos a partir dos espectros de fluorescência de excitação-emissão de amostras de misturas farmacêuticas com excipiente amido/celulose, e amostras utilizando como excipiente a lactose. Excelentes resultados de previsão foram obtidos, com erros relativos abaixo de 5%. Também, comprovou-se que os resultados de previsão obtidos a partir dos dados de transferência de calibração aplicados ao modelo UPLS, não apresentam diferença em relação a previsão de amostras idênticas às usadas no modelo de calibração / Abstract: In this work it was developed a methodology for determination of acetylsalicylic acid (ASA), paracetamol and caffeine in pharmaceutical formulations using solidphase molecular fluorescence and second order calibration methods. This methodology is usefull even in the presence of unknown interferences and with spectral overlap of the components in the mixture. Parallel Factor Analysis (PARAFAC) and Unfolded Partial Least Squares (UPLS) were used for second order calibration models development. Errors below to 5% were obtained for all compounds using an external validation set. Advantages not included in the reference methods such as low cost, no need of sample preparation, simple and fast analysis and no generation of waste, make this method very attractive, allowing to the simultaneous determination of compounds with good reproducibility and accuracy. Also, to propose a solution for the problem observed during the models development, due to change of sample matrix, the transfer of calibration was used. In this study it was used the method of Piecewise Direct Standardization applied to UPLS models constructed from samples of pharmaceutical mixtures of acetilsalicilic acid (ASA), paracetamol and caffeine with starch/cellulose 1:1 as excipient and samples with lactose as excipient, for accomplishment of the calibration transfer procedures. The transfer of calibration through Piecewise Direct Standardization method (PDS) applied to the UPLS calibration models provided excellent prediction results for pharmaceutical mixture in diferent excipient with relative errors less than 5%. From the values of RMSEP obtained for the results of the models of reference and the models of calibration transference, it was evaluated through a F test, that there is no difference, with 99% of significance level, in the results obtained by two models / Mestrado / Quimica Analitica / Mestre em Química
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Fluorescent molecular sensors based on photoresponsive modified β-cyclodextrin and crown ethers for detecting organic molecules and metal ions in waterNcube, Phendukani 09 December 2013 (has links)
D.Phil. (Chemistry) / The problem of maintaining good quality of water for domestic use and for aquatic life remains a challenge. Water sources are often contaminated with pollutants from natural sources such as volcanic eruptions and by human activities such as manufacturing industries, mining, water-purification processes, agricultural activities and a vast number of other activities. Water-purification processes used by municipal authorities are designed to remove most of the pollutants but some trace amounts will always remain and have been detected in drinking water and treated waste water reservoirs. These trace amounts pose a threat to human health and the well-being of aquatic life. The detection of these trace amounts of pollutants is often carried out by laboratory-based techniques that require sophisticated, expensive instruments and often require extensive sample preparation and pre-concentration. Simple, quick and in-field detection methods are necessary especially for remote small communities with limited or no access to laboratories. Optical detection systems offer hope as a solution to this problem. In this work newly developed fluorescence-based molecular sensors for the detection of pollutants in water were developed, characterised and tested for their sensing abilities towards organic and inorganic pollutants. The fluorescent probes for organic pollutants were designed based on the host-guest chemistry of the cyclodextrin molecule. Azo dye-modified β-cyclodextrins were synthesised and linked via ethylene glycol and epichlorohydrin to produce the sensors that were then tested for their sensing response towards chlorophenols and small aliphatic chlorinated alkanes which are often formed during the disinfection of water in the purification process. The sensor molecules were characterised by UV-Vis, FT-IR and 1D and 2D NMR spectroscopy. The amount of cyclodextrin in each sensor molecule was quantified using the anthrone method (67%) as well as by 1H-NMR spectroscopy (72%). To demonstrate the host-guest interaction of the sensor molecules, isothermal titration calorimetry (ITC) was used. ITC measurements showed that modifying β-cyclodextrin and using linkers did not alter its host-guest interaction with guest molecules as demonstrated by the stoichiometry, n, stability (or binding or association) constant (K) and thermodynamic parameters of the interaction. The sensor molecule linked via ethylene glycol showed selectivity towards 4- chlorophenol among the chlorophenols investigated and has the potential to be used in a sensor for the detection of 4-chlorophenol. The sensor molecule linked via epichlorohydrin showed sensitivity towards chloroform, a typical disinfection by-product. These experimental results showed that the sensor molecules could be used for quick on-field detection of chlorinated organic compounds in water. Sensor molecules for inorganic pollutants were based on the complex formation of crown ethers with metal ions. The sensor was formed by modifying a dibenzo-18- crown-6 ether molecule with an azo dye. The sensor was then characterised using UV-Vis spectrophotmetry, FT-IR and NMR spectroscopies as well as mass spectrometry and CHNS elemental analysis. The sensor molecule was then subjected to different metal ions and the fluorescence change of the probe observed. Interestingly, the sensor was highly sensitive and selective to mercury (II) and Cu (II) ions in water. Mercury (II) is one of the most hazardous heavy metals among the heavy-metal ions found in environmental waters and its early detection in water sources is important. The synthesised molecular sensor can therefore be incorporated into a simple hand-held gadget with a light source and be used for on-field detection of mercury (II) ions in remote areas.
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Bepaling van spoorelemente in uraanertse met behulp van X-straalfluoressensie-spektrometrieDe Villiers, Wessel van Zyl 10 April 2014 (has links)
M.Sc. (Chemistry) / The determination of 17 trace elements (As. Ba. Co. Cr. Cu. Mo. Nb. Ni. Pb. Rb. Sr. Th. U. V. Y. Zn and Zr) in uranium ores by X-ray fluorescence spectrometry was investigated in this study. The determination of major elements. however. was also necessary for the calculation of mass absorption coefficients. Major elements were determined on borate melts and trace elements on powder briquettes pressed at 7 t with a binder in liquid form. Initially a method was developed for the determination of the elements of interest in unmineralised rocks The rhodium tube was used for the Group 1 elements (As. Mo. Nb. Pb, Bb, Sr. Th, U. Y and Zr) and the gold tube for the Group 2 elements [Ba, Co. Cr. Cu. Ni. V and Zn). Background and peak overlap corrections were made by means of background and interference factors. Corrections for absorption of radiation by the sample were made by means of mass absorption coefficients. which were calculated from the major element composition or obtained from the relation between the inverse of the mass absorption coefficient and the intensity of the Compton scattering peak. Due to various problems. only the latter method was suitable for uranium ores. The high uranium content in uranium ores mainly affected the Group 1 elements. Because of the high intensity of various UL lines. large overlap corrections were necessary. while only a few completely interference-free background positions were available. Consequently. the Feather and Willis method was used for determining the background intensity at the peak positions as well as for mass absorption coefficients. As a result of the presence of the UL absorption edges both primarx and secondary mass absorption coefficients had to be used for matrix corrections. Furthermore. it was observed that the background intensity in the region of the uranium lines increases with increasing uranium content of the sample instead of the expected decrease due to the increasing mass absorption coefficient. This effect was greater for the LiF(11 0) crystal than for the LiF(100) and was attributed to the scattering of uranium lines in the spectrometer chamber. especially from the crystal. A method was developed to correct the measured intensities for this scattering effect. Calibration lines of the contribution from the scattering of uranium lines to the measured intensity at the different 28 positions versus the uranium peak intensity were plotted by using samples with various uranium concentrations (<2 %) and for which the mass absorption coefficients and concentrations of the various elements were known. The precision of the method was less than 2.5 % at concentrations greater than 50 ppm. With the exception of barium. detection limits varied between 1 and 5 ppm. Accurate results were obtained over large concentration ranges for various unmineralised samples and for uranium ores. The results of the analysis of a number of Karoo uranium ores are given.
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Spectrofluorometric studies on the role of tryptophan in the catalytic mechanism of NADPH-elaterinide... - oxidoreductase from Cucurbita MaximaDirr, Heinrich Wilfred 10 June 2014 (has links)
M.Sc. (Biochemistry) / Please refer to full text to view abstract
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