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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Caracteriza??o t?rmica e desenvolvimento de m?todo anal?tico para determina??o simult?nea das guanilhidrazonas WE005, WE015 e WE016

Dantas, Monique Gomes 06 February 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-10-26T20:21:40Z No. of bitstreams: 1 MoniqueGomesDantas_DISSERT.pdf: 3471537 bytes, checksum: a73f34ecbaa2b638849e2cfdb0b85408 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-12-20T18:08:05Z (GMT) No. of bitstreams: 1 MoniqueGomesDantas_DISSERT.pdf: 3471537 bytes, checksum: a73f34ecbaa2b638849e2cfdb0b85408 (MD5) / Made available in DSpace on 2016-12-20T18:08:05Z (GMT). No. of bitstreams: 1 MoniqueGomesDantas_DISSERT.pdf: 3471537 bytes, checksum: a73f34ecbaa2b638849e2cfdb0b85408 (MD5) Previous issue date: 2015-02-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Guanilhidrazonas s?o uma classe de subst?ncias amplamente estudadas por apresentar grande potencial biol?gico. A an?lise de f?rmacos e medicamentos ? ferramenta importante para garantir qualidade, seguran?a e efic?cia aos novos medicamentos. Nesse estudo foram avaliadas as guanilhidrazonas sint?ticas WE005 (3,4-dimetoxibenzalde?doguanilhidrazona), WE015 (benzalde?doguanilhidrazona) e WE016 (metil-4-formilbenzoatoguanilhidrazona) com o objetivo de caracterizar, desenvolver e validar m?todo anal?tico utilizando t?cnicas t?rmicas (DSC e TG), espectrosc?pica (FTIR), microsc?pica (MEV) e cromatogr?fica (CLUE/DAD). Na caracteriza??o por DSC e TG foram utilizadas as seguintes raz?es de aquecimento: 2,5; 5,0; 10 e 20 ?C/min em atmosfera de nitrog?nio (50 mL/min) at? 500?C (DSC) e 900?C (TG). A an?lise na regi?o do infravermelho m?dio das mol?culas foi realizada a temperatura ambiente e na faixa de fus?o. Os espectros foram comparados atrav?s da correla??o de Pearson utilizando o algoritmo ad hoc. O estudo cin?tico foi feito atrav?s do m?todo de Ozawa. O planejamento fatorial investigou a influ?ncia do comprimento da coluna, fluxo e propor??o de fase m?vel sobre o tempo de reten??o, fator de cauda, resolu??o e n?mero de pratos te?ricos. As t?cnicas t?rmicas foram capazes de caracterizar as mol?culas atrav?s de suas transi??es de fase e etapas na curva termogravim?trica, informando ainda sobre a estabilidade t?rmica, com temperatura inicial de decomposi??o em torno de 240 ?C. O estudo cin?tico mostrou que todas as mol?culas apresentam ordem zero e que a amostra WE016 apresentou maior energia de ativa??o. Os espectros de infravermelho de acordo com a correla??o de Pearson apresentaram mudan?as significativas entre a temperatura ambiente e o espectro da faixa de fus?o. O planejamento fatorial atrav?s dos gr?ficos de superf?cie-resposta e Pareto revelou que a vari?vel de maior influ?ncia sobre todas as vari?veis dependentes foi o comprimento da coluna. O melhor m?todo para a separa??o das guanilhidrazonas deste estudo foi: coluna C18 (50 mm x 2 mm t.p. 2.2 ?m), fase m?vel MeOH:H2O:TEA 40:60:0,1, pH 3,5 ajustado com ?cido ac?tico; fluxo de 0,2 mL/min, temperatura do forno 30 ?C. A concentra??o final das guanilhidrazonas foi de 30 ?g/mL e foram detectadas simultaneamente atrav?s do comprimento de onda de 290 nm. Um m?todo r?pido foi desenvolvido para separar as guanilhidrazonas WE005, WE015 E WE016 por CLUE/DAD. Planejamento fatorial foi uma ferramenta ?til para o desenvolvimento racional do m?todo. / Guanilhidrazonas substances are widely studied for presenting great biological potential, especially antitumor activity, antimicrobial, antimalarial, antifungal and anti-hypertensive. This study assessed the synthetic guanylhydrazones WE005 ((2-[(3,4-dimethoxyphenyl)methylene]-hydrazinecarboximidamide),WE015 (2(phenylmethylene)-hydrazinecarboximidamide) and WE016 (4-[[2-(aminoiminomethyl) hydrazinylidene]methyl]-benzoic acid methyl ester) in order to characterize and develop analytical method using thermal techniques (DSC and TGA), spectroscopic (FTIR ) and microscopic (SEM) and chromatographic (UHPLC / DAD). The characterization by DSC and TG were used the following heating rates: 2.5; 5.0; 10 and 20 ? C / min in a nitrogen atmosphere (50 ml / min) to 500 ? C (DSC) and 900 ? C (TG). The kinetic study was done by Ozawa method. The analysis in the mid-infrared region of molecules was performed at room temperature and the melting temperature. The spectra were compared using Pearson's correlation using ad hoc algorithm. For the development of the analytical method was used factorial design. Thermal techniques have been able to characterize the molecules through their phase transitions and steps in the thermogravimetric curve, and telling about the thermal stability, with an initial decomposition temperature of about 240 ? C. The kinetic study showed that the speed of the thermal decomposition of molecules has zero order and that the WE016 sample showed higher activation energy. Infrared spectra according to the Pearson correlation showed significant changes between the room temperature and the melting range of the spectrum. The factorial design through surface-response graphs and Pareto showed that the most influential variable on all dependent variables was the length of the column. The best method for the separation of guanylhydrazones this study was: C18 column (50 mm x 2 mm tp 2.2 microns), mobile phase MeOH: H2 O: TEA 40: 60: 0.1, pH 3.5 adjusted with acetic acid; flow rate of 0.2 ml / min, oven temperature 30 ? C. The final concentration of guanylhydrazones was 30 mg / mL and were detected simultaneously by a wavelength of 290 nm. A rapid method was developed to separate guanylhydrazones WE005, WE015 and WE016 by CLUE / DAD. Factorial design was a useful tool for the rational development of the method.
2

Desenvolvimento e valida??o de m?todo anal?tico para determina??o de diferentes guanilhidrazonas

Brito, Wanessa Azevedo de 26 March 2014 (has links)
Made available in DSpace on 2014-12-17T14:16:37Z (GMT). No. of bitstreams: 1 WanessaAB_DISSERT.pdf: 3799185 bytes, checksum: ce77744774059676a04175b60c73d121 (MD5) Previous issue date: 2014-03-26 / The synthetic guanylhydrazones WE010 (3,5-di-tert-butil-4-hidroxibenzaldehyde-guanylhydrazone), WE014 (4-bifenilcarboxialdehydeguanylhydrazone) and WE017 (3,4-diclorobenzaldehydeguanylhydrazone) showed high cytotoxic activity in terms of percentage inhibition of cancer cells growth. However, further progress in the development of these drug candidates requires precise and convenient methods for their qualitative and quantitative analyses. The aim of this study was to develop and validate High Performance Liquid Chromatography with diode-array detection (HPLC-DAD) and Ultra Fast Liquid Chromatography with diode-array detection (UFLC-DAD) methods suitable for as simultaneous as isolated determination of studied guanylhydrazones, based on the optimization of chromatographic parameters and obtaining reduced detection times. The chromatographic analyses of analytes by HPLC were performed on C18 ACE analytical column (150 mm x 4.6 mm), with a particle size of 5.0 ?m. Among all the conditions assayed, the best results of separation were obtained with a mixture of methanol:water (60:40, v/v) as the mobile phase at a flow rate 1.5mL/min and pH of 3.5 adjusted at acetic acid. The UFLC method was developed by experimetal desing techniques in order to find optimal chromatographic analytical conditions, which were achieved on XR-ODS analytical column (50 mm x 3.0 mm), with a particle size of 2,2 ?m, maintained at 25 ?C. The mobile phase was consisted of methanol:water (65:35, v/v) with 0.1% triethylamine (TEA) and pH of 3.5 adjusted at acetic acid, at a flow rate 0.5 mL/min. The procedure were validated following evaluating parameters such as specificity, linearity, limits of detection (LD) and quantification (LQ), precision, accuracy and robustness, giving results within the acceptable range. Although the UFLC method shows better sensitivity (lower values of LD and LQ), robustness (lower rates of relative standard deviation) and minimize spending time and solvent, both developed methods were adequately applied to the analysis of guanylhydrazones molecules, may be used in routine of quality control laboratories. Keywords: guanylhydrazones, HPLC/DAD, UFLC/DAD, validation of analitical method / As guanilhidrazonas sint?ticas WE010 (3,5-di-tert-butil-4-hidroxibenzalde?do-guanilhidrazona), WE014 (4-bifenilcarboxialde?doguanilhidrazona) e WE017 (3,4-diclorobenzalde?doguanilhidrazona) apresentaram alta atividade citot?xica em rela??o a inibi??o do crescimento de c?lulas cancer?genas. Contudo, o avan?o no desenvolvimento desses candidatos a f?rmacos necessitam de m?todos precisos para suas adequadas an?lises quantitativas e qualitativas. O objetivo desse estudo foi desenvolver e validar m?todos por Cromatografia L?quida de Alta Efici?cia com Detector de Arranjo Diodo (CLAE-DAD) e Cromatografia L?quida de Ultra Efici?cia com Detector de Arranjo Diodo (CLUE-DAD) adequados para a determina??o simult?nea, bem como isolada das guanilhidrazonas em estudo, baseado na otimiza??o de par?metros cromatogr?ficos e obten??o de tempos reduzidos de detec??o. As an?lises cromatogr?ficas por CLAE foram realizadas numa coluna anal?tica C18 ACE (150 mm x 4,6 mm), com tamanho de part?cula de 5,0 ?m. Dentre as condi??es analisadas, os melhores resultados de separa??o foram obtidos com uma fase m?vel composta por metanol:?gua (60:40), em um fluxo de 1,5 mL/min. e um pH de 3,5 ajustado com ?cido ac?tico. O m?todo por CLUE foi desenvolvido a partir de t?cnicas de planejamento fatorial, com o objetivo de se encontrar as melhores condi??es anal?ticas, que foram obtidas a partir de an?lise em uma coluna XR-ODS (50 mm x 3,0 mm), com tamanho de part?cula de 2,2 ?m, mantida a 25 ?C. A fase m?vel foi constitu?da por metanol:?gua (65:35) com 0,1% de Trietilamina (TEA) e pH de 3,5 ajustado com ?cido ac?tico. Os procedimentos foram validados a partir da avalia??o de par?metros de especificidade, linearidade, limites de detec??o (LD) e quantifica??o (LQ), precis?o exatid?o e robustez, obtendo-se resultados dentro do intervalo aceit?vel. Embora o m?todo por CLUE tenha mostrado melhor sensibilidade (menores valores de LD e LQ), robustez (menores ?ndices de desvio padr?o relativo) e minimizado gastos de tempo e solvente, ambos os m?todos desenvolvidos foram adequadamente aptos para as an?lises das mol?culas de guanilhidrazonas, podendo ser utilizados na rotina de laborat?rios de controle de qualidade

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