In this study, polyelectrolyte membranes were prepared by layer-by-layer self-assembly on top of an interfacially polymerized polyamide substrate, and these thin-film-composite membranes were studied for pervaporative dehydration of ethylene glycol, ethanol and isopropanol. The performance of composite membranes based on polyethylenimine/poly(acrylic acid) (PEI/PAA) multilayers on a polyamide substrate showed good selectivity and stability for ethylene glycol dehydration. In order to understand the formation process of the polyelectrolyte multilayers, the growth of polyelectrolyte multilayers fabricated on the inner surface of cuvette was investiagted. The membrane surface became increasingly hydrophilic with an increase in the number of polyelectrolyte double layers, which favored water permeation for pervaporative dehydration of organic solvents. Water contact angle on the membrane surface decreased from 68?? to 20?? when 7 polyelectrolyte bilayers were deposited on the polyamide substrate. Although the (PEI/PAA) based polyelectrolyte membranes showed good performance for dehydration of ethylene glycol, these membranes did not perform well for the dehydration of ethanol and isopropanol at relatively high feed alcohol concentrations. This was found to be caused by insufficient stability of PEI/PAA bilayers and the polyamide substrate in the ethanol and isopropanol. To improve the performance of the composite membranes for dehydration of ethanol and isopropanol, the outermost surface layer was deposited with PEI, followed by crosslinking. A further improvement in the membrane selectivity was accomplished by substituting the PEI with partially protonated chitosan in the last few polyelectrolyte bilayers during membrane fabrication. It was demonstrated that using interfacially polymerized polyamide membrane as a substrate, polyelectrolyte membranes with less than 8 bilayers could be fabricated for the dehydration of alcohol and diol. This represents a siginificant advancement as a large number of polyelectrolyte bilayers (as many as 60) are often needed. Glutaraldehyde crosslinked polyelectrolyte self-assembled membranes comprising of chitosan and PAA were also prepared for isopropanol/water separation. The resulting membrane showed stable performance with good permeation flux and separation factor. The effects of crosslinking conditions (e.g., concentration and temperature of crosslinking agent, and crosslinking time) on the membrane performance were studied. Alternatively, using PEI as polycation, when anionic PAA was substituted with alginate in the last few polyelectrolyte bilayers during membrane fabrication, stable membranes with a good performance were obtained without the need of chemical crosslinking. The polyethylenimine/alginate self-assembly membranes showed good selectivity and stability for dehydration of ethanol. For instance, a permeation flux of 0.24 kg/(??? h) and a separation factor of 206 were obtained at room temperature at 10 wt% feed water concentration with a membrane comprising of 10 double layers of polyelectrolytes.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-09T14:22:46Z No. of bitstreams: 2 Dissertação - Alarisse Arçari Fachetti Zoghaib - 2015.pdf: 1188040 bytes, checksum: 9ab52dc612351ab19ab98e90e7ce6ec9 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-09T14:24:14Z (GMT) No. of bitstreams: 2 Dissertação - Alarisse Arçari Fachetti Zoghaib - 2015.pdf: 1188040 bytes, checksum: 9ab52dc612351ab19ab98e90e7ce6ec9 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-09T14:24:14Z (GMT). No. of bitstreams: 2 Dissertação - Alarisse Arçari Fachetti Zoghaib - 2015.pdf: 1188040 bytes, checksum: 9ab52dc612351ab19ab98e90e7ce6ec9 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-09-28 / The ruthenium (II)/amino acid complex (rutrpII) demonstrated high anticancer activity against murine breast cancer (tumor of Ehrlich) in vitro and in vivo, and increased the median survival of animals. There was then necessary to investigate the pharmacokinetic parameters of the drug prototype as a requirement to pre-clinical knowledge of it. This study aimed to obtain the pharmacokinetic profile of ruthenium (II) / tryptophan administered to rats intraperitoneally in a single dose by quantifying this substance in plasma using validated analytical methodology in UV-VIS spectrophotometer. The methodology consisted of the administration of the prototype rutrpII to 3 rats at a dose of 6 mg/kg, intraperitoneally. Samples of blood 1.0 ml were collected by cannulation of the left jugular vein with heparinized syringe, the intervals from 0 to 9 hr. After centrifugation the plasma was frozen at -20 until the time of analysis. The bioanalytical method to quantify rutrpII was developed and validated in UV-VIS at a wavelength of 417 nm. From the construction of the concentration versus time curve, the kinetic parameters were calculated (Software WinNonlin 5.0 (Pharsight ™) Results were: Tmax = 8 h, Cmax = 169.86 mg/mL, t1/2 = 1.04 ± 0.02 h, ClT/F = 1.32 ± 0.05 mL/min/kg, Vd/F = 1,98 ± 0,05 L/kg. The developed and validated bioanalytical method was suitable for the detection and quantification of RutrpII in rat plasma. The values of pharmacokinetic profiles found, and extrapolated on allometric scaling allow us to understand that the compound studied showed a slow tissue distribution profile and / or was eliminated slowly (Vd low and low value CLT), due to a possible affinity between RutrpII and plasma proteins. This affinity may be explained by the similarity of their chemical structure with iron, enabling it to be transported by biomolecules such as transferrin, albumin or any other, and having as a target the DNA of cancer cells. In general, the compounds of ruthenium (II) / amino acids may be promising drugs for the amino acids present in the complex, may facilitate the recognition of the complex as a whole by DNA, and thus less toxic. / O complexo de rutênio(II)/aminoácido (rutrpII) demonstrou alta atividade antineoplásica contra carcinoma de mama murino (tumor de Ehrlich) in vitro e in vivo, sendo que neste último, aumentou a média de sobrevida dos animais. Fez-se necessária então a investigação dos parâmetros farmacocinéticos deste protótipo de fármaco como requisito ao conhecimento pré-clínico do mesmo. O objetivo deste trabalho foi obter o perfil farmacocinético do rutênio(II)/triptofano administrado a ratos, via intraperitoneal, em dose única por meio da quantificação desta substância em plasma utilizando metodologia analítica validada em espectrofotômetro UV-VIS. A metodologia consistiu na administração do protótipo rutrpII a 3 ratos em dose de 6 mg/kg, por via intraperitonal. Foram coletadas amostras de 1,0 mL de sangue, por canulação da veia jugular esquerda, com seringa heparinizada, nos intervalos de tempo de 0 a 9 h. Após centrifugação, o plasma foi congelado a -20ºC até o momento da análise. O método bioanalítico de quantificação do rutrpII foi desenvolvido e validado em espectrofotômetro UV-VIS no comprimento de onda de 417 nm. A partir da construção da curva de concentração versus tempo, foram calculados os parâmetros cinéticos (Software Winnonlin 5.0 (Pharsight™)). Os resultados encontrados foram: Tmax= 8h, Cmax= 169,86 µg/mL, t(1/2) =1,04 ± 0,02 h,ClT/F = 1,32 ± 0,05 mL/min/kg, Vd/F = 1,98 ± 0,05 L/kg. O método bioanalítico desenvolvido e validado foi adequado para a detecção e quantificação do RutrpII em plasma de rato. Os valores dos perfis farmacocinéticos encontrados, e extrapolados em escala alométrica, permitem entender que o composto estudado apresentou um perfil lento de distribuição tecidual e/ou foi eliminado lentamente (baixo Vd e baixo valor de CLT), devido a uma possível afinidade entre o RutrpII e as proteínas plasmáticas. Esta afinidade pode ser explicada pela semelhança de sua estrutura química com o ferro, possibilitando que ele seja transportado por biomoléculas como a transferrina, albumina ou alguma outra, e tendo como alvo, o DNA da células cancerosas. De maneira geral os compostos de rutênio(II)/ aminoácidos podem ser fármacos promissores pois os aminoácidos presentes nos complexos, podem facilitar o reconhecimento do complexo como um todo pelo DNA, sendo assim menos tóxicos.