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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.
11

Óleo essencial de casca-preciosa (Aniba canelilla (H. B. K. ) Mez) : validação de metodologia bioanalítica e estudo de permeação cutânea in vitro / “Precious-bark” essential oil (Aniba canelilla (H. B. K.) Mez) : bioanalytical method validation and in vitro cutaneous permeation study

Kreutz, Tainá January 2017 (has links)
A Aniba canelilla (H.B.K.) Mez é uma planta aromática proveniente da região amazônica cujo óleo essencial apresenta como componentes majoritários o 1-nitro-2-feniletano e o metileugenol. Apesar das atividades antifúngicas e anti-inflamatórias cientificamente comprovadas e do uso popular do óleo para o tratamento de dermatites, acnes e feridas, não existe até o momento um estudo que verse sobre a quantificação desses compostos na pele. O objetivo deste trabalho foi a validação de um método bioanalítico otimizado por microextração em fase sólida no modo headspace em cromatógrafo gasoso com detector de ionização de chama (HS-SPME-GC-FID) para a determinação do 1-nitro-2-feniletano e metileugenol a partir do óleo essencial em diferentes amostras de estudo de permeação cutânea in vitro. Uma metodologia foi desenvolvida e validada por HS-SPME-GC-FID. A faixa da curva de calibração foi de 2,08 - 207,87 μg.mL-1 para o 1-nitro-2-feniletano e de 0,40-40,41 μg.mL-1 para o metileugenol. A presença de matriz e as características intrínsecas da metodologia de HS-SPME requereram uma transformação da curva de calibração. A transformação logarítmica (Log10) foi então aplicada aos dados e os resultados apresentaram homocedasticidade, resíduos dispersos, coeficiente de determinação (r²> 0,99) e recuperação adequados. Estudos de permeação cutânea foram realizados em células de Franz com diferentes quantidades (20, 100 e 200 μL) de óleo essencial de A. canelilla para avaliar o perfil de permeação e retenção em pele de orelha suína e fluido receptor. A análise das amostras nas condições validadas mostrou uma grande permeação e retenção dos compostos na seguinte ordem: fluido receptor >> derme >> epiderme >> estrato córneo. Verificou-se um aumento progressivo e dependência na retenção com base na quantidade aplicada no compartimento doador e grande retenção principalmente no fluido receptor e derme, resultado este compatível com as características físico-químicas de Log P, afinidade ao ambiente hidrofílico e lipofílico, tamanho e peso molecular do 1-nitro-2-feniletano e metileugenol. Em conclusão, o método proposto por HS-SPME-GC-FID para quantificar os compostos majoritários do óleo essencial de A. canelilla em amostras de pele de orelha suína e fluido receptor foi seletivo, preciso, exato e adequado, e pode ser utilizado em análises futuras. / Aniba canelilla (H.B.K.) Mez is an aromatic plant from the Amazon region whose essential oil has 1-nitro-2-phenylethane and methyleugenol as major compounds. Despite of the scientifically proved antifungal and anti-inflammatory activities and the popular use of oil for the treatment of dermatitis, acnes and wounds, there is no study up to date about the quantification of these compounds in skin samples. The aim of this study was the validation of an optimized bioanalytical method by solid phase microextraction on headspace mode in gas chromatograph with flame ionization detector (HS-SPME-GC-FID) for the determination of 1-nitro-2-phenylethane and methyleugenol from the essential oil in different samples of in vitro cutaneous permeation study. A methodology was developed and validated by HS-SPME-GC-FID. The ranges of calibration curves were 2.08 - 207.87 μg.mL-1 for 1-nitro-2-phenylethane and 0.40 - 40.41 μg.mL-1 for methyleugenol. The presence of matrix and the intrinsic characteristics of the HS-SPME methodology required a transformation to the calibration curves. The logarithmic transformation (Log10) was then applied to the data and the results showed homoscedasticity, dispersed residues, and adequate coefficient of determination (r²> 0.99) and recovery. Skin permeation studies were performed on Franz cells with different amounts (20, 100 and 200 μL) of A. canelilla essential oil to evaluate the skin permeation and retention profile in porcine ear skin and receptor fluid. The analysis of the samples under the validated conditions showed a high permeation and retention of the major compounds in the following order: receptor fluid >> dermis >> epidermis >> stratum corneum. A progressive increase and retention dependence were observed based on the amount applied in the donor compartment, and large retention mainly on the receptor fluid and dermis was observed, in accordance with the physicochemical characteristics of Log P, affinity to the hydrophilic and lipophilic environment, size and molecular weight of 1-nitro-2-phenylethane and methyleugenol. In conclusion, the method proposed by HS-SPME-GC-FID to quantify the major compounds of A. canelilla essential oil in porcine ear skin and receptor fluid samples was selective, accurate, precise and adequate, and can be used in future analyzes.
12

The Study of Interfacial Dynamics at Biochemically Modified Surfaces Using Acoustic Wave Physics and Molecular Simulations

Ellis, Jonathan S. 15 July 2009 (has links)
Detection of conformational and structural shifts in biomolecules is of great importance in bioanalytical chemistry and pharmaceutical sciences. Transverse shear mode acoustic wave devices have been used as real-time, label-free detectors of conformational shifts in biomolecules on surfaces. However, material changes in the biochemical monolayer and coupling between the substrate and the surrounding liquid make it difficult to isolate the desired signal, so an understanding of these phenomena is required. In this thesis, interfacial slip, viscoelasticity, and structural changes are used to model acoustic signals due to surface adsorption of the protein neutravidin, immobilisation of HIV-1 TAR RNA, and subsequent interaction of the RNA with tat peptide fragments. Binding of tat peptides induces conformational changes in the TAR. Similar modelling is performed to describe experiments involving the binding of calcium to surface-attached calmodulin, which is also known to result in a conformational shift. The aim of the modelling is to isolate the sensor response due to conformational shifts. The biomolecules are described as hydrated, viscoelastic monolayers and slip is allowed at all interfaces. All models are numerically fit to experimental values using a two-parameter minimisation algorithm. Slip is found on the electrode surface prior to neutravidin adsorption. Neutravidin and TAR are described as distinct viscoelastic monolayers. Binding of tat peptide fragment to the TAR monolayer is modelled using a complex slip parameter and a change in length, corresponding to a straightening of the molecule. Similarly, numerical modelling of calmodulin results reveals a length change in the molecule upon calcium binding. Molecular dynamics (MD) simulations of the TAR-tat fragment system are performed to corroborate the modelling results. Starting structures are computed by molecular docking, and MD simulations of TAR complexed with various length tat fragments are described. The simulations are in general agreement with the modelling results and literature values from similar molecular dynamics experiment. A new parameter is introduced to describe biomolecule-solvent affinity, and is compared to interfacial coupling values obtained from modelling. This research demonstrates that acoustic wave devices can be used to detect conformational shifts in surface-attached biomolecules, provided molecular details about the shifts are known.
13

The Study of Interfacial Dynamics at Biochemically Modified Surfaces Using Acoustic Wave Physics and Molecular Simulations

Ellis, Jonathan S. 15 July 2009 (has links)
Detection of conformational and structural shifts in biomolecules is of great importance in bioanalytical chemistry and pharmaceutical sciences. Transverse shear mode acoustic wave devices have been used as real-time, label-free detectors of conformational shifts in biomolecules on surfaces. However, material changes in the biochemical monolayer and coupling between the substrate and the surrounding liquid make it difficult to isolate the desired signal, so an understanding of these phenomena is required. In this thesis, interfacial slip, viscoelasticity, and structural changes are used to model acoustic signals due to surface adsorption of the protein neutravidin, immobilisation of HIV-1 TAR RNA, and subsequent interaction of the RNA with tat peptide fragments. Binding of tat peptides induces conformational changes in the TAR. Similar modelling is performed to describe experiments involving the binding of calcium to surface-attached calmodulin, which is also known to result in a conformational shift. The aim of the modelling is to isolate the sensor response due to conformational shifts. The biomolecules are described as hydrated, viscoelastic monolayers and slip is allowed at all interfaces. All models are numerically fit to experimental values using a two-parameter minimisation algorithm. Slip is found on the electrode surface prior to neutravidin adsorption. Neutravidin and TAR are described as distinct viscoelastic monolayers. Binding of tat peptide fragment to the TAR monolayer is modelled using a complex slip parameter and a change in length, corresponding to a straightening of the molecule. Similarly, numerical modelling of calmodulin results reveals a length change in the molecule upon calcium binding. Molecular dynamics (MD) simulations of the TAR-tat fragment system are performed to corroborate the modelling results. Starting structures are computed by molecular docking, and MD simulations of TAR complexed with various length tat fragments are described. The simulations are in general agreement with the modelling results and literature values from similar molecular dynamics experiment. A new parameter is introduced to describe biomolecule-solvent affinity, and is compared to interfacial coupling values obtained from modelling. This research demonstrates that acoustic wave devices can be used to detect conformational shifts in surface-attached biomolecules, provided molecular details about the shifts are known.
14

Extraction of therapeutic proteins from dried blood spots and their analysis on Gyrolab

Garbergs, Hanna January 2011 (has links)
A method for extraction of therapeutic proteins from dried blood spots (DBS) followed by quantification on Gyrolab(TM) has been developed. The method makes it possible to measure the concentration of the analyte in the range 100-6000 ng/mL. The procedure can generate full analytical information from 15 μL blood originally sampled from a subject. The modest sample requirements allows for sampling a full pre-clinical pharmacokinetic profile from a single mouse. This may allow for reduced usage of animals during preclinical development of new therapeutic proteins in accordance with the 3R’s, replace, refine and reduce.
15

Óleo essencial de casca-preciosa (Aniba canelilla (H. B. K. ) Mez) : validação de metodologia bioanalítica e estudo de permeação cutânea in vitro / “Precious-bark” essential oil (Aniba canelilla (H. B. K.) Mez) : bioanalytical method validation and in vitro cutaneous permeation study

Kreutz, Tainá January 2017 (has links)
A Aniba canelilla (H.B.K.) Mez é uma planta aromática proveniente da região amazônica cujo óleo essencial apresenta como componentes majoritários o 1-nitro-2-feniletano e o metileugenol. Apesar das atividades antifúngicas e anti-inflamatórias cientificamente comprovadas e do uso popular do óleo para o tratamento de dermatites, acnes e feridas, não existe até o momento um estudo que verse sobre a quantificação desses compostos na pele. O objetivo deste trabalho foi a validação de um método bioanalítico otimizado por microextração em fase sólida no modo headspace em cromatógrafo gasoso com detector de ionização de chama (HS-SPME-GC-FID) para a determinação do 1-nitro-2-feniletano e metileugenol a partir do óleo essencial em diferentes amostras de estudo de permeação cutânea in vitro. Uma metodologia foi desenvolvida e validada por HS-SPME-GC-FID. A faixa da curva de calibração foi de 2,08 - 207,87 μg.mL-1 para o 1-nitro-2-feniletano e de 0,40-40,41 μg.mL-1 para o metileugenol. A presença de matriz e as características intrínsecas da metodologia de HS-SPME requereram uma transformação da curva de calibração. A transformação logarítmica (Log10) foi então aplicada aos dados e os resultados apresentaram homocedasticidade, resíduos dispersos, coeficiente de determinação (r²> 0,99) e recuperação adequados. Estudos de permeação cutânea foram realizados em células de Franz com diferentes quantidades (20, 100 e 200 μL) de óleo essencial de A. canelilla para avaliar o perfil de permeação e retenção em pele de orelha suína e fluido receptor. A análise das amostras nas condições validadas mostrou uma grande permeação e retenção dos compostos na seguinte ordem: fluido receptor >> derme >> epiderme >> estrato córneo. Verificou-se um aumento progressivo e dependência na retenção com base na quantidade aplicada no compartimento doador e grande retenção principalmente no fluido receptor e derme, resultado este compatível com as características físico-químicas de Log P, afinidade ao ambiente hidrofílico e lipofílico, tamanho e peso molecular do 1-nitro-2-feniletano e metileugenol. Em conclusão, o método proposto por HS-SPME-GC-FID para quantificar os compostos majoritários do óleo essencial de A. canelilla em amostras de pele de orelha suína e fluido receptor foi seletivo, preciso, exato e adequado, e pode ser utilizado em análises futuras. / Aniba canelilla (H.B.K.) Mez is an aromatic plant from the Amazon region whose essential oil has 1-nitro-2-phenylethane and methyleugenol as major compounds. Despite of the scientifically proved antifungal and anti-inflammatory activities and the popular use of oil for the treatment of dermatitis, acnes and wounds, there is no study up to date about the quantification of these compounds in skin samples. The aim of this study was the validation of an optimized bioanalytical method by solid phase microextraction on headspace mode in gas chromatograph with flame ionization detector (HS-SPME-GC-FID) for the determination of 1-nitro-2-phenylethane and methyleugenol from the essential oil in different samples of in vitro cutaneous permeation study. A methodology was developed and validated by HS-SPME-GC-FID. The ranges of calibration curves were 2.08 - 207.87 μg.mL-1 for 1-nitro-2-phenylethane and 0.40 - 40.41 μg.mL-1 for methyleugenol. The presence of matrix and the intrinsic characteristics of the HS-SPME methodology required a transformation to the calibration curves. The logarithmic transformation (Log10) was then applied to the data and the results showed homoscedasticity, dispersed residues, and adequate coefficient of determination (r²> 0.99) and recovery. Skin permeation studies were performed on Franz cells with different amounts (20, 100 and 200 μL) of A. canelilla essential oil to evaluate the skin permeation and retention profile in porcine ear skin and receptor fluid. The analysis of the samples under the validated conditions showed a high permeation and retention of the major compounds in the following order: receptor fluid >> dermis >> epidermis >> stratum corneum. A progressive increase and retention dependence were observed based on the amount applied in the donor compartment, and large retention mainly on the receptor fluid and dermis was observed, in accordance with the physicochemical characteristics of Log P, affinity to the hydrophilic and lipophilic environment, size and molecular weight of 1-nitro-2-phenylethane and methyleugenol. In conclusion, the method proposed by HS-SPME-GC-FID to quantify the major compounds of A. canelilla essential oil in porcine ear skin and receptor fluid samples was selective, accurate, precise and adequate, and can be used in future analyzes.
16

Ultrafine Dielectrophoresis-based Technique for Virus and Biofluid Manipulation

January 2017 (has links)
abstract: Microfluidics has shown great potential in rapid isolation, sorting, and concentration of bioparticles upon its discovery. Over the past decades, significant improvements have been made in device fabrication techniques and microfluidic methodologies. As a result, considerable microfluidic-based isolation and concentration techniques have been developed, particularly for rapid pathogen detection. Among all microfluidic techniques, dielectrophoresis (DEP) is one of the most effective and efficient techniques to quickly isolate and separate polarizable particles under inhomogeneous electric field. To date, extensive studies have demonstrated that DEP devices are able to precisely manipulate cells ranging from over 10 μm (mammalian cells) down to about 1 μm (small bacteria). However, very limited DEP studies on manipulating submicron bioparticles, such as viruses, have been reported. In this dissertation, rapid capture and concentration of two different and representative types of virus particles (Sindbis virus and bacteriophage M13) with gradient insulator-based DEP (g-iDEP) has been demonstrated. Sindbis virus has a near-spherical shape with a diameter ~68 nm, while bacteriophage M13 has a filamentous shape with a length ~900 nm and a diameter ~6 nm. Under specific g-iDEP experimental conditions, the concentration of Sindbis virus can be increased two to six times within only a few seconds, using easily accessible voltages as low as 70 V. A similar phenomenon is also observed with bacteriophage M13. Meanwhile, their different DEP behavior predicts the potential of separating viruses with carefully designed microchannels and choices of experimental condition. DEP-based microfluidics also shows great potential in manipulating blood samples, specifically rapid separations of blood cells and proteins. To investigate the ability of g-iDEP device in blood sample manipulation, some proofs of principle work was accomplished including separating two cardiac disease-related proteins (myoglobin and heart-type fatty acid binding protein) and red blood cells (RBCs). Consistent separation was observed, showing retention of RBCs and passage of the two spiked protein biomarkers. The numerical concentration of RBCs was reduced (~70 percent after one minute) with the purified proteins available for detection or further processing. This study explores and extends the use of the device from differentiating similar particles to acting as a sample pretreatment step. / Dissertation/Thesis / Doctoral Dissertation Chemistry 2017
17

Óleo essencial de casca-preciosa (Aniba canelilla (H. B. K. ) Mez) : validação de metodologia bioanalítica e estudo de permeação cutânea in vitro / “Precious-bark” essential oil (Aniba canelilla (H. B. K.) Mez) : bioanalytical method validation and in vitro cutaneous permeation study

Kreutz, Tainá January 2017 (has links)
A Aniba canelilla (H.B.K.) Mez é uma planta aromática proveniente da região amazônica cujo óleo essencial apresenta como componentes majoritários o 1-nitro-2-feniletano e o metileugenol. Apesar das atividades antifúngicas e anti-inflamatórias cientificamente comprovadas e do uso popular do óleo para o tratamento de dermatites, acnes e feridas, não existe até o momento um estudo que verse sobre a quantificação desses compostos na pele. O objetivo deste trabalho foi a validação de um método bioanalítico otimizado por microextração em fase sólida no modo headspace em cromatógrafo gasoso com detector de ionização de chama (HS-SPME-GC-FID) para a determinação do 1-nitro-2-feniletano e metileugenol a partir do óleo essencial em diferentes amostras de estudo de permeação cutânea in vitro. Uma metodologia foi desenvolvida e validada por HS-SPME-GC-FID. A faixa da curva de calibração foi de 2,08 - 207,87 μg.mL-1 para o 1-nitro-2-feniletano e de 0,40-40,41 μg.mL-1 para o metileugenol. A presença de matriz e as características intrínsecas da metodologia de HS-SPME requereram uma transformação da curva de calibração. A transformação logarítmica (Log10) foi então aplicada aos dados e os resultados apresentaram homocedasticidade, resíduos dispersos, coeficiente de determinação (r²> 0,99) e recuperação adequados. Estudos de permeação cutânea foram realizados em células de Franz com diferentes quantidades (20, 100 e 200 μL) de óleo essencial de A. canelilla para avaliar o perfil de permeação e retenção em pele de orelha suína e fluido receptor. A análise das amostras nas condições validadas mostrou uma grande permeação e retenção dos compostos na seguinte ordem: fluido receptor >> derme >> epiderme >> estrato córneo. Verificou-se um aumento progressivo e dependência na retenção com base na quantidade aplicada no compartimento doador e grande retenção principalmente no fluido receptor e derme, resultado este compatível com as características físico-químicas de Log P, afinidade ao ambiente hidrofílico e lipofílico, tamanho e peso molecular do 1-nitro-2-feniletano e metileugenol. Em conclusão, o método proposto por HS-SPME-GC-FID para quantificar os compostos majoritários do óleo essencial de A. canelilla em amostras de pele de orelha suína e fluido receptor foi seletivo, preciso, exato e adequado, e pode ser utilizado em análises futuras. / Aniba canelilla (H.B.K.) Mez is an aromatic plant from the Amazon region whose essential oil has 1-nitro-2-phenylethane and methyleugenol as major compounds. Despite of the scientifically proved antifungal and anti-inflammatory activities and the popular use of oil for the treatment of dermatitis, acnes and wounds, there is no study up to date about the quantification of these compounds in skin samples. The aim of this study was the validation of an optimized bioanalytical method by solid phase microextraction on headspace mode in gas chromatograph with flame ionization detector (HS-SPME-GC-FID) for the determination of 1-nitro-2-phenylethane and methyleugenol from the essential oil in different samples of in vitro cutaneous permeation study. A methodology was developed and validated by HS-SPME-GC-FID. The ranges of calibration curves were 2.08 - 207.87 μg.mL-1 for 1-nitro-2-phenylethane and 0.40 - 40.41 μg.mL-1 for methyleugenol. The presence of matrix and the intrinsic characteristics of the HS-SPME methodology required a transformation to the calibration curves. The logarithmic transformation (Log10) was then applied to the data and the results showed homoscedasticity, dispersed residues, and adequate coefficient of determination (r²> 0.99) and recovery. Skin permeation studies were performed on Franz cells with different amounts (20, 100 and 200 μL) of A. canelilla essential oil to evaluate the skin permeation and retention profile in porcine ear skin and receptor fluid. The analysis of the samples under the validated conditions showed a high permeation and retention of the major compounds in the following order: receptor fluid >> dermis >> epidermis >> stratum corneum. A progressive increase and retention dependence were observed based on the amount applied in the donor compartment, and large retention mainly on the receptor fluid and dermis was observed, in accordance with the physicochemical characteristics of Log P, affinity to the hydrophilic and lipophilic environment, size and molecular weight of 1-nitro-2-phenylethane and methyleugenol. In conclusion, the method proposed by HS-SPME-GC-FID to quantify the major compounds of A. canelilla essential oil in porcine ear skin and receptor fluid samples was selective, accurate, precise and adequate, and can be used in future analyzes.
18

Obtenção e caracterização química e farmacocinética do produto de fotodegradação do nifedipino / Obtaining and chemical characterization of nifedipine

Oliveira, Maysa Aparecida de 16 July 2013 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2018-07-09T16:12:59Z No. of bitstreams: 2 Tese- Maysa Aparecida de Oliveira - 2013.pdf: 2303389 bytes, checksum: d6b1b0186001f327c5e50809b8d401fb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-07-10T11:10:17Z (GMT) No. of bitstreams: 2 Tese- Maysa Aparecida de Oliveira - 2013.pdf: 2303389 bytes, checksum: d6b1b0186001f327c5e50809b8d401fb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-07-10T11:10:17Z (GMT). No. of bitstreams: 2 Tese- Maysa Aparecida de Oliveira - 2013.pdf: 2303389 bytes, checksum: d6b1b0186001f327c5e50809b8d401fb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2013-07-16 / A simple and accurate stability-indicating high-performance liquid chromatography (HPLC-DAD) method was developed to measure nifedipine (NIF) in plasma in the presence of its degradation products. The chromatographic separation was performed on a C18 column using H3PO4 0.01%:CH3CN:CH3OH (60:20:20, v/v/v) as the mobile phase and a 1.0ml/min flow rate. The analytical validation was performed according to FDA, EMA and ANVISA (Brazilian Health Surveillance Agency) guidelines and was linear between 100.0 and 2000.0 ng/ml, precise (1.9 to 11.3%) and accurate (86.0 to 113.1%). Under the evaluated conditions, NIF in plasma samples were stable after processing and freeze-thaw cycles. The average liquid-liquid extraction recovery was 101.3 ± 5.4%. After validation, this method was applied to evaluate the influence of nitrosophenylpyridine (NO-NIF) in the pharmacokinetic of NIF in plasma of Wistar rats. This method was also validated for quality control of NO-NIF obtained after photodegradation of NIF in photostability chamber. The method showed selectivity, linearity (0.4 to 2.4mg/ml), as well as precision and accuracy. Nitrophenylpyridine (NINIF) was synthesized from the NIF. These degradation products were characterized by NMR and mass spectroscopy. In addition, a breakdown product of NO-NIF due to its contact with plasma was identified and characterized. / Um método simples, rápido e preciso por cromatografia líquida de alta eficiência (HPLC-DAD) foi desenvolvido para determinação de nifedipino (NIF) na presença de seus produtos de degradação em amostras de plasma. A separação cromatográfica foi realizada em coluna C18 empregando H3PO4 0,01%:CH3CN:CH3OH (60:20:20 v/v/v) como fase móvel e vazão de 1,0mL/min. A validação procedeu-se segundo as recomendações dos guias editados pela ANVISA, EMA e FDA e apresentou linearidade no intervalo de 100,0 a 2000,0ng/mL com precisão (1,9 a 11,3%) e exatidão 86,0 a 113,1%) adequadas. Nas condições avaliadas, as amostras de NIF mostraram-se estáveis tanto em plasma como após processamento e ciclos de congelamento e descongelamento. A eficiência do método de extração líquido-líquido demonstrou recuperação média de 101,3 ± 5,4%. Após a etapa de validação, o método foi aplicado em estudos farmacocinéticos para avaliação da influência do nitrosofenilpiridino (NO-NIF) na farmacocinética do NIF. Este método também foi validado para o controle de qualidade do NO-NIF obtido após fotodegradação do NIF em câmara de fotoestabilidade e apresentou seletividade, linearidade (0,4 a 2,4μg/mL), assim como precisão e exatidão. Além da obtenção do NO-NIF por fotodegradação, nitrofenilpiridino (NI-NIF) foi sintetizado a partir do NIF. Esses produtos de degradação foram caracterizados por RMN e espectrometria de massas. Além disso, um produto de degradação do NO-NIF decorrente do seu contato com plasma foi identificado e caracterizado.
19

Determinação Quantitativa de um Derivado Tiazolidínico (3-(2-bromo-benzil)-5-(5-bromo-2-metoxi-benzilideno)-tiazolidina-2,4-diona) em Plasma de Ratos Wistar: Desenvolvimento e Validação de um Método Analítico Recife

SILVA, Ricardo Martins 30 May 2011 (has links)
Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-04-04T19:21:33Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) 2011-Dissertação-RicardoSilva.pdf: 2010474 bytes, checksum: fa5ce1fda4e849fa7743b5d5b4e55481 (MD5) / Made available in DSpace on 2017-04-04T19:21:33Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) 2011-Dissertação-RicardoSilva.pdf: 2010474 bytes, checksum: fa5ce1fda4e849fa7743b5d5b4e55481 (MD5) Previous issue date: 2011-05-30 / Dentre vários compostos sintetizados pelo Laboratório de Planejamento e Síntese de Fármacos (LPSF) da Universidade Federal de Pernambuco, o derivado tiazolidínico (3-(2-Bromo-benzil)-5-(5-bromo-2-metoxi-benzilideno)-tiazolidina-2,4-diona) (LPSF/GQ-113B) apresentou importante atividade antiinflamatória em ratos Wistar. Tal resultado despertou nosso interesse no desenvolvimento e validação de um método bioanalítco para determinação do LPSF/GQ-113B em fluídos biológicos. Nesse contexto, um método bioanalítico sensível e seletivo foi desenvolvido e validado utilizando a técnica de Cromatografia Líquida de Alta Eficiência acoplada a um detector ultravioleta (CLAE-UV) para quantificação do LPSF/GQ-113B em plasma de ratos Wistar. O método envolveu precipitação das proteínas plasmática com acetonitrila e, o LPSF/GQ-113B foi separado utilizando uma fase móvel composta por uma mistura de acetonitrila/água e ácido acético (85:14:1 v/v/v) eluida de forma isocrática através de uma coluna analítica Phenomenex® C18 5μ (150mm x 4.6mm) a uma temperatura de 40 ºC. O comprimento de onda para a detecção foi de 254 nm. A curva de calibração foi linear na faixa de 500-16000 ng/ml/L, com coeficientes de determinação (r²) próximos da unidade (0.997-0.999). Os rendimentos de extração para as concentrações de 1500, 7500 e 13.000 ng/ml/L foram 94.2%, 92.2% e 97.3%, respectivamente. O limite de quantificação para o LPSF/GQ-113B foi de 500 ng/mL. A validação do método incluiu a análise dos parâmetros analíticos de exatidão e precisão intra-dia e inter-dia que se apresentaram dentro dos limites exigidos pela legislação pertinente. Dessa forma, o método proposto pode ser aplicado para determinação quantitativa do LPSF/GQ-113B em plasma de ratos Wistar em estudos farmacológicos, toxicológicos, farmacocinéticos e de biodisponibilidade. / Among several compounds synthesized by the Laboratory of Planning and Synthesis of Drugs, from Federal University of Pernambuco, the thiazolidine derivative (3 - (2-bromo-benzyl) -5 - (5-bromo-2-methoxy-benzylidene)-thiazolidine -2,4-dione) (LPSF/GQ-113B) showed significant antiinflammatory activity in rats. This result has stimulated our interest in the development and validation of a method for determining LPSF/GQ-113B in biological fluids. In this context a fast, sensitive, and selective detection has been developed and validated for quantifying LPSF/GQ-113B in rat plasma by high-performance liquid chromatography coupled UV detector method . A plasma protein precipitation method was used with acetonitrile and, LPSF/GQ-113B was separated using a mobile phase (acetonitrile/water/acetic acid (85:14:1 v/v/v)) on the analytical column Phenomenex ® C18 5μm ( 150mm x 4.6mm) stored into the oven at 40 ºC temperature. The wavelength selected for detection was 254 nm. Over the range 500-16000 ng/mL, the calibration curve was linear with coefficient of determination (r²) were close to unit (0.997564- 0.999765). The recoveries at concentrations of 500, 7500 and 13000 ng/mL were 94.2%, 92.2% and 97.3%. The lower limit of quantification obtained was 500 ng/mL. Validation of the method included analysis of the analytical parameters of accuracy and within-batch and between-batch were inside the limits required by the competent authorities. Thus, the proposed method can be applied for quantitative determination of LPSF/GQ-113B in plasma of Wistar rats in pharmacological studies, toxicological, pharmacokinetic and bioavailability.
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FTIR imaging of collagens in gliomas / Imagerie IRTF des contenus en collagènes des gliomes

Noreen, Razia 27 September 2011 (has links)
Le gliome est le type le plus agressif et mortel de tumeur cérébrale. Ces tumeurs se caractérisent par la présence conjointe de phénotypes solides (de bas grade, moins invasif, hautement vascularisé) et diffus (haut grade, très envahissant et diffus) des glioblastomes multiformes. Les collagènes sont des composants majeurs de la MEC des cellules tumorales des gliomes, et sont également présents dans la membrane basale des vaisseaux sanguins, mais avec une composition différente entre vasculatures saine et tumorale. L'abondance et la typologie des collagènes dans la MEC des cellules tumorales et la vasculature représentent donc un marqueur potentiel de diagnostic pour la gradation des tumeurs gliales. Nous avons développé la spectro-imagerie infrarouge à transformée de Fourier pour déterminer les modifications morphologiques et moléculaires apparaissant dans les formes solides et diffuses de gliomes, ainsi que dans les vasculatures saine et tumorale. Nous avons d'abord mis en évidence les vasculatures saine et tumorale en utilisant des nanoparticules injectées dans le système sanguin. Ensuite, nous avons appliqué des méthodes de reconstruction spectrale pour distinguer les tissus sains vs. ceux des formes solide et diffuse de tumeurs sur la base de leurs contenus en collagène de la MEC. Enfin, nous avons déterminé les changements de types du collagène au cours de la progression tumorale, validant ainsi la notion que l’analyse de ces contenus est potentiellement un marqueur diagnostic pour la gradation des gliomes. / The glioma is the most aggressive and lethal type of brain tumor. Such tumor is characterized both by solid (low grade, less invasive, highly vascularized) and diffuse (high grade, very invasive and diffuse) phenotypes in high-grades. Collagens are major components of ECM in glioma tumor cells, and are also present in basement membrane of blood vessels in vasculature, but with different composition between healthy and tumor capillaries. The abundance and typology of collagens in tumor cell ECM and vasculature is thus a potential diagnostic marker for grading glioma tumors. We developed Fourier transform infrared (FTIR) spectro-imaging as a functional technique to determine the morphological and molecular changes occurring in solid and diffuse form of tumor tissues as well as in healthy and tumor vasculatures. We first highlighted healthy and tumor vasculatures using nanoparticles injected in blood system. Then, we applied curve-fitting methods to distinguish between healthy tissue vs. solid and diffuse tumor tissues on the basis of the collagen contents found in ECM. Finally, we determined collagen typology changes during tumor progression, thus validating that collagen contents analysis is potentially a diagnostic marker for glioma grading.

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