Este trabalho apresenta a síntese, caracterização e estudo fotofísico de novos heterociclos benzazólicos fluorescentes com potencial aplicação como sondas de ambientes lipídicos. Para isso, foram sintetizados três corantes que contêm em sua estrutura cadeias alquílicas de oito, doze e dezoito átomos de carbono ligados a um núcleo benzazólico que é o responsável pela fluorescência destes compostos. O corante que possui a cadeia alquílica de dezoito carbonos apresenta-se ainda na forma de um sal de amônio quaternário, com o objetivo de tornar a sua estrutura mais anfifílica do que os seus análogos neutros de oito e doze carbonos, e com isso, promover a interação entre meios que apresentam polaridade diferente como, por exemplo, água e membrana. A obtenção dos derivados contendo oito e doze carbonos foi realizada a partir da reação de substituição nucleofílica entre o heterociclo 2-(5’-amino-2’-hidroxifenil)benzoxazol e os respectivos iodoalcanos em presença de uma base, com rendimentos na faixa de 45%. O derivado com dezoito carbonos foi obtido em duas etapas, sendo a primeira a reação entre o 2- (5’-amino-2’-hidroxifenil)benzoxazol e a epicloridrina para formar o intermediário 2-(5’(N-3- cloro-2-hidroxipropilamina)-2’-hidroxifenil)benzoxazol. A reação deste intermediário com a N,N-dimetiloctadecilamina levou a formação do corante na forma de sal de amônio quaternário com 68% de rendimento. Os corantes foram caracterizados por Infravermelho, Ressonância Magnética Nuclear de Hidrogênio e de Carbono, Análise Elementar e ponto de fusão, além da caracterização fotofísica. O estudo fotofísico do sistema fosfatidilcolina/corante mostrou que os corantes sofrem a influência do meio lipídico, bem como a afinidade do corante quaternizado pelo sistema lipídico diferencia-se dos corantes neutros. Além disso, os corantes com cadeias alquílicas de oito e doze átomos de carbono se mostraram sondas mais eficientes para meios apolares ou polares apróticos e são liberados para o meio com o aumento da diluição do sistema. Já o corante com cadeia alquílica de dezoito átomos de carbono apresentou maior afinidade com o ambiente hidrofílico do sistema lipídico, ficando incorporado na bicamada lipídica, mesmo com o aumento da diluição. / This work presents the synthesis, characterization and photophysical study of new fluorescent benzazólicos heterocycles with potential application as probes of lipid environments. For this, three dyes were synthesized containing alkyl chains in the structure of eight, twelve and eighteen carbon atoms attached to a core benzazólico which is responsible for the fluorescence of these compounds. The dye that has the alkyl chain of eighteen carbons still presents as a quaternary ammonium salt, with the goal of making its structure more amphiphilic than their neutral analogues of eight and twelve carbons, and thereby promote the interaction means that present different polarity, for example, water and membrane. The obtaining of derivatives containing eight twelve carbons was made from the nucleophilic substitution reaction between the heterocycle 2-(5'-amino-2'-hydroxyphenyl) benzoxazole and its iodoalcanos in the presence of a base, with yields around 45%. The derivative eighteen carbons was obtained in two steps, the first being the reaction between 2- (5'-amino-2'-hydroxyphenyl) benzoxazole and epichlorohydrin to form the intermediate 2- (5'(N-3-chloro-2-hydroxypropylamine)-2'-hydroxyphenyl) benzoxazole. The reaction of this intermediate with N, N-dimetiloctadecilamina led to the formation of the desired compound quaternised 68% yield. The compounds were characterized by infrared, nuclear magnetic resonance of hydrogen and carbon, elemental analysis and melting point, besides the characterization photophysics. The photophysical study of the phosphatidylcholine/dye system showed that the dyes suffer the influence of the lipid and affinity of the dye quaternized by the system differs from dyes that show no load. In addition, the neutral dyes with alkyl chains content eight and twelve carbon atoms, proved most interesting probes for apolar media or polar aprotic media and are released into the medium with increasing dilution of the system. Already the derivative with eighteen carbon atoms and having quaternary nitrogen showed higher affinity for hydrophilic environment lipid system, becoming incorporated into the lipid bilayer, even with increased dilution.

Cancer mortality is progression-dependent thus its treatment relies on effective therapy and monitoring of responses. Nanoparticles have long been used to improve the therapeutic index of drugs by facilitating their transit to the target site at higher concentrations than free drugs, whilst protecting healthy tissues from an often potent and cytotoxic payload. Through the EPR (enhanced permeability and retention) effect, injected, PEGylated nanoparticles preferentially accumulate in tumour tissue deeming them eminently suitable for cancer intervention for delivery of both therapeutic and contrast agents The development of theranostic liposomal systems comprising both imaging and therapeutic capabilities exploits the facets of liposomes, and forms an elegant strategy to address major problems which hinder effective cancer therapy. Liposomes can be tailored to be thermosensitive in a low hyperthermic range of ~42°C, above physiological temperature but below that which can induce tissue damage. This allows the use of heating as an external triggering modality to induce targeted drug release. Throughout the course of this work, the photoacoustic contrast agent ICG was successfully incorporated into PEGylated doxorubicin-encapsulating liposomes, marrying two FDA approved entities. The project commenced with the development of the basic liposomal-DOX. Differing lipid compositions of varying fluidities were tested against those which have been previously established. These compositions carried a range of phase transition temperatures, above which the liposomes release the encapsulated DOX. This study concluded with the generation of a library of liposomes with differing release kinetics at 42°C in simulated physiological conditions. The second section of the project investigated the methodology behind the incorporation of ICG into the liposomal bilayers. The lipid composition used for the study was based on the DOXIL® formulation, due to its robust structure and establishment in the field of cancer therapy. The protocols used varied on the basis of chronology in regards to the liposome preparation protocol. The film insertion method incorporated the ICG in initial lipid film generation. The freeze fracture protocol introduced the ICG during lipid film hydration. The post insertion protocol introduced ICG in the final stages of DOX loading. The downsizing protocol was also varied between extrusion and sonication. Through varying of the protocols and downsizing methodology, it was possible to incorporate differing ICG concentrations and attain differing levels of structural stability. The most successful liposome was then tested for its imaging potential in vivo through a photoacoustic imaging modality namely multispectral optoacoustic tomography. This validated accumulation of the liposomes at the tumour site along with co-localisation of both drug and dye. The project culminated in the combination of the two studies, producing a thermosensitive theranostic ICG labelled liposomal doxorubicin system. The system showed improved blood stability than the current clinical systems, and demonstrated imaging potential through IVIS based fluorescence imaging. Through exploitation of the photothermal effects of ICG within a thermosensitive lipid vesicle, it was also possible to induce drug release through irradiation with a non-thermal near-infrared laser. This shows promise for future therapy, allowing simultaneous imaging, optimum release induction and monitoring response to therapy, in a cheap, effective and time-efficient manner.

Este trabalho apresenta a síntese, caracterização e estudo fotofísico de novos heterociclos benzazólicos fluorescentes com potencial aplicação como sondas de ambientes lipídicos. Para isso, foram sintetizados três corantes que contêm em sua estrutura cadeias alquílicas de oito, doze e dezoito átomos de carbono ligados a um núcleo benzazólico que é o responsável pela fluorescência destes compostos. O corante que possui a cadeia alquílica de dezoito carbonos apresenta-se ainda na forma de um sal de amônio quaternário, com o objetivo de tornar a sua estrutura mais anfifílica do que os seus análogos neutros de oito e doze carbonos, e com isso, promover a interação entre meios que apresentam polaridade diferente como, por exemplo, água e membrana. A obtenção dos derivados contendo oito e doze carbonos foi realizada a partir da reação de substituição nucleofílica entre o heterociclo 2-(5’-amino-2’-hidroxifenil)benzoxazol e os respectivos iodoalcanos em presença de uma base, com rendimentos na faixa de 45%. O derivado com dezoito carbonos foi obtido em duas etapas, sendo a primeira a reação entre o 2- (5’-amino-2’-hidroxifenil)benzoxazol e a epicloridrina para formar o intermediário 2-(5’(N-3- cloro-2-hidroxipropilamina)-2’-hidroxifenil)benzoxazol. A reação deste intermediário com a N,N-dimetiloctadecilamina levou a formação do corante na forma de sal de amônio quaternário com 68% de rendimento. Os corantes foram caracterizados por Infravermelho, Ressonância Magnética Nuclear de Hidrogênio e de Carbono, Análise Elementar e ponto de fusão, além da caracterização fotofísica. O estudo fotofísico do sistema fosfatidilcolina/corante mostrou que os corantes sofrem a influência do meio lipídico, bem como a afinidade do corante quaternizado pelo sistema lipídico diferencia-se dos corantes neutros. Além disso, os corantes com cadeias alquílicas de oito e doze átomos de carbono se mostraram sondas mais eficientes para meios apolares ou polares apróticos e são liberados para o meio com o aumento da diluição do sistema. Já o corante com cadeia alquílica de dezoito átomos de carbono apresentou maior afinidade com o ambiente hidrofílico do sistema lipídico, ficando incorporado na bicamada lipídica, mesmo com o aumento da diluição. / This work presents the synthesis, characterization and photophysical study of new fluorescent benzazólicos heterocycles with potential application as probes of lipid environments. For this, three dyes were synthesized containing alkyl chains in the structure of eight, twelve and eighteen carbon atoms attached to a core benzazólico which is responsible for the fluorescence of these compounds. The dye that has the alkyl chain of eighteen carbons still presents as a quaternary ammonium salt, with the goal of making its structure more amphiphilic than their neutral analogues of eight and twelve carbons, and thereby promote the interaction means that present different polarity, for example, water and membrane. The obtaining of derivatives containing eight twelve carbons was made from the nucleophilic substitution reaction between the heterocycle 2-(5'-amino-2'-hydroxyphenyl) benzoxazole and its iodoalcanos in the presence of a base, with yields around 45%. The derivative eighteen carbons was obtained in two steps, the first being the reaction between 2- (5'-amino-2'-hydroxyphenyl) benzoxazole and epichlorohydrin to form the intermediate 2- (5'(N-3-chloro-2-hydroxypropylamine)-2'-hydroxyphenyl) benzoxazole. The reaction of this intermediate with N, N-dimetiloctadecilamina led to the formation of the desired compound quaternised 68% yield. The compounds were characterized by infrared, nuclear magnetic resonance of hydrogen and carbon, elemental analysis and melting point, besides the characterization photophysics. The photophysical study of the phosphatidylcholine/dye system showed that the dyes suffer the influence of the lipid and affinity of the dye quaternized by the system differs from dyes that show no load. In addition, the neutral dyes with alkyl chains content eight and twelve carbon atoms, proved most interesting probes for apolar media or polar aprotic media and are released into the medium with increasing dilution of the system. Already the derivative with eighteen carbon atoms and having quaternary nitrogen showed higher affinity for hydrophilic environment lipid system, becoming incorporated into the lipid bilayer, even with increased dilution.

Este trabalho apresenta a síntese, caracterização e estudo fotofísico de novos heterociclos benzazólicos fluorescentes com potencial aplicação como sondas de ambientes lipídicos. Para isso, foram sintetizados três corantes que contêm em sua estrutura cadeias alquílicas de oito, doze e dezoito átomos de carbono ligados a um núcleo benzazólico que é o responsável pela fluorescência destes compostos. O corante que possui a cadeia alquílica de dezoito carbonos apresenta-se ainda na forma de um sal de amônio quaternário, com o objetivo de tornar a sua estrutura mais anfifílica do que os seus análogos neutros de oito e doze carbonos, e com isso, promover a interação entre meios que apresentam polaridade diferente como, por exemplo, água e membrana. A obtenção dos derivados contendo oito e doze carbonos foi realizada a partir da reação de substituição nucleofílica entre o heterociclo 2-(5’-amino-2’-hidroxifenil)benzoxazol e os respectivos iodoalcanos em presença de uma base, com rendimentos na faixa de 45%. O derivado com dezoito carbonos foi obtido em duas etapas, sendo a primeira a reação entre o 2- (5’-amino-2’-hidroxifenil)benzoxazol e a epicloridrina para formar o intermediário 2-(5’(N-3- cloro-2-hidroxipropilamina)-2’-hidroxifenil)benzoxazol. A reação deste intermediário com a N,N-dimetiloctadecilamina levou a formação do corante na forma de sal de amônio quaternário com 68% de rendimento. Os corantes foram caracterizados por Infravermelho, Ressonância Magnética Nuclear de Hidrogênio e de Carbono, Análise Elementar e ponto de fusão, além da caracterização fotofísica. O estudo fotofísico do sistema fosfatidilcolina/corante mostrou que os corantes sofrem a influência do meio lipídico, bem como a afinidade do corante quaternizado pelo sistema lipídico diferencia-se dos corantes neutros. Além disso, os corantes com cadeias alquílicas de oito e doze átomos de carbono se mostraram sondas mais eficientes para meios apolares ou polares apróticos e são liberados para o meio com o aumento da diluição do sistema. Já o corante com cadeia alquílica de dezoito átomos de carbono apresentou maior afinidade com o ambiente hidrofílico do sistema lipídico, ficando incorporado na bicamada lipídica, mesmo com o aumento da diluição. / This work presents the synthesis, characterization and photophysical study of new fluorescent benzazólicos heterocycles with potential application as probes of lipid environments. For this, three dyes were synthesized containing alkyl chains in the structure of eight, twelve and eighteen carbon atoms attached to a core benzazólico which is responsible for the fluorescence of these compounds. The dye that has the alkyl chain of eighteen carbons still presents as a quaternary ammonium salt, with the goal of making its structure more amphiphilic than their neutral analogues of eight and twelve carbons, and thereby promote the interaction means that present different polarity, for example, water and membrane. The obtaining of derivatives containing eight twelve carbons was made from the nucleophilic substitution reaction between the heterocycle 2-(5'-amino-2'-hydroxyphenyl) benzoxazole and its iodoalcanos in the presence of a base, with yields around 45%. The derivative eighteen carbons was obtained in two steps, the first being the reaction between 2- (5'-amino-2'-hydroxyphenyl) benzoxazole and epichlorohydrin to form the intermediate 2- (5'(N-3-chloro-2-hydroxypropylamine)-2'-hydroxyphenyl) benzoxazole. The reaction of this intermediate with N, N-dimetiloctadecilamina led to the formation of the desired compound quaternised 68% yield. The compounds were characterized by infrared, nuclear magnetic resonance of hydrogen and carbon, elemental analysis and melting point, besides the characterization photophysics. The photophysical study of the phosphatidylcholine/dye system showed that the dyes suffer the influence of the lipid and affinity of the dye quaternized by the system differs from dyes that show no load. In addition, the neutral dyes with alkyl chains content eight and twelve carbon atoms, proved most interesting probes for apolar media or polar aprotic media and are released into the medium with increasing dilution of the system. Already the derivative with eighteen carbon atoms and having quaternary nitrogen showed higher affinity for hydrophilic environment lipid system, becoming incorporated into the lipid bilayer, even with increased dilution.

Orientador: Silmara Marques Allegretti / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-09T03:19:37Z (GMT). No. of bitstreams: 1 Frezza_TarsilaFerraz_M.pdf: 1047879 bytes, checksum: 74e06a87b1d60512f1a9f3f80aeb6639 (MD5) Previous issue date: 2007 / Resumo: Para o tratamento da esquistossomose mansônica no Brasil, a Oxamniquina (OXA) e o Praziquantel (PRZ) são os fármacos escolhidos. O primeiro tem sua produção reduzida por causa dos efeitos colaterais, carcinogênicos e mutagênicos que apresenta. O segundo tem amplo espectro de atuação e baixa toxicidade, quando comparado ao OXA, mas tem a desvantagem de ser eliminado rapidamente pelo organismo. Além disso, tem ação dependente da idade do parasito e seu uso extensivo culmina na resistência do Schistosoma mansoni ao fármaco. Assim, o estudo de novas alternativas que tornem o PRZ mais disponível no organismo, com taxa de liberação mais adequada, é necessário. Uma dessas alternativas é sua incorporação ao lipossoma (LPZ). O presente trabalho teve por objetivo analisar o efeito do PRZ incorporado a LPZ (PRZ+LPZ) pela sua ação na sobrevida dos vermes adultos de S. mansoni, linhagem BH, e alteração na postura dos ovos além da sua ação na formação de granulomas no fígado. Foram testadas cinco doses de PRZ livre e PRZ+LPZ (40; 47; 60; 250 e 300 mg/kg) em camundongos Swiss, administradas por meio da tubagem esofágica, em dose única. Os lipossomas de fosfatidilcolina foram preparados pelo método da sonicação. Os camundongos foram divididos em dois grandes grupos (um deles foi tratado após 30 dias de infecção e o outro após 45 dias) sendo que em cada grupo, dez animais receberam uma determinada dose de PRZ a ser testada, para os outros dez a mesma dose, dessa vez com o PRZ+LPZ e para os dez restantes, Tampão Tris HCl pH 7,5. Após 15 dias da administração do tratamento, os animais foram sacrificados e necrospsiados. O tratamento feito com PRZ+LPZ na dose de 300 mg/kg, administrado no 45º dia de infecção, mostrou-se mais eficaz para a maioria dos parâmetros analisados (maior quantidade de vermes fora do sistema porta-hepático ¿ indicando uma resposta do verme à ação do fármaco - maior redução no número de vermes e de ovos nas fezes e maior redução dos ovos viáveis no intestino ¿ principalmente dos imaturos). Provavelmente, este tratamento alterou a oviposição do verme. Os órgãos dos camundongos tratados com PRZ+LPZ na dose 300 mg/kg, administrado no 30º dia de infecção, apresentaram poucas lesões. Além disso, não apresentaram granulomas nos fígados observados histologicamente, o que pode ser explicado pela baixa oviposição que ocorre nesse período, com o fato deste tratamento talvez ter a capacidade de minimizar a formação dos granulomas. O tratamento feito com PRZ+LPZ foi superior provavelmente porque aumentou a disponibilidade do fármaco no organismo assim como a sua solubilidade em meios aquosos. Além disso, o fármaco, quando incorporado, provavelmente foi absorvido com mais facilidade pelo verme, fazendo com que os danos provocados pelo PRZ no parasito, fossem mais profundos / Abstract: For the treatment of schistosomiasis mansoni in Brazil, the drugs of choice are Oxamniquina (OXA) and the Praziquantel (PRZ). OXA has its production reduced by its collateral, carcinogenic and mutagenic effects that it presents. PRZ has wide action spectrum and low toxicity, when compared to OXA. However, it has the disadvantage of being eliminated very fast by the organism. Besides, it has its action depending on the age of the parasite and its extensive use leads to a resistance of the Schistosoma mansoni to the drug. It¿s necessary the research of new alternatives to make PRZ more available in the organism, with more adequate liberation rate. One of these alternatives is its incorporation to the liposome (LPZ). The current work had as a target to analyze the effect of the PRZ incorporated to LPZ (PRZ+LPZ) by its action in the survival of adult worms of Schistosoma mansoni, BH strain, and alteration in the laying of eggs beyond its action in the formation of granulomas in the liver. Five doses were tested of PRZ e PRZ+LPZ (40; 47; 60; 250 and 300 mg/kg) in Swiss mice, administered by the intragastric route in only one dose. The liposomes of phosphatidilcoline were prepared by the method of sonication. The mice were divided in two big groups (one of them was treated after 30 days of infection and the other group treated after 45 days) and in each group ten animals received a determined dose of PRZ to be tested, to the other ten the same dose, this time with PRZ+LPZ and to the last ten, Busser Tris HCl pH 7,5. After 15 days of the administration of the treatment, the animals were sacrificed and necropsies. The treatment done with PRZ+LPZ in the dose of 300 mg/kg, administered of the 45th day of the infection, showed itself superior to the majority of the analyzed parameters (higher quantity of worms outside the porta-hepatic system ¿which indicates a response of the worm to the action of the drug -, big reduction in the number of worms and eggs in the fezzes and big reduction of the viable eggs in the intestines ¿ mainly of immature eggs). Probably this treatment altered the oviposition of the worm. The organs of mice treated with PRZ+LPZ in dose of 300 mg/kg, administered in the 30est day of infection, presented fewer injuries. Besides, they don¿t show granulomas in the livers observed histological, which can be explained by the low oviposition that occurs in this period, with the fact that this treatment perhaps having the capacity of minimize the formation of granulomas. The treatment done with PRZ+LPZ was superior probably because the availability increased of the drug in the organism as well its solubility in water environment. Besides, the drug, when incorporated, probably was more easily absorbed by the worm, making the harm provoqued by PRZ deeper / Mestrado / Mestre em Parasitologia

Submitted by Erika Demachki (erikademachki@gmail.com) on 2015-10-21T17:09:00Z No. of bitstreams: 2 Dissertação - Monalisa Martins Trentini - 2014.pdf: 3160453 bytes, checksum: bcd4f593c1bbefa247afd83aa66ef627 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Erika Demachki (erikademachki@gmail.com) on 2015-10-21T17:16:56Z (GMT) No. of bitstreams: 2 Dissertação - Monalisa Martins Trentini - 2014.pdf: 3160453 bytes, checksum: bcd4f593c1bbefa247afd83aa66ef627 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-10-21T17:16:56Z (GMT). No. of bitstreams: 2 Dissertação - Monalisa Martins Trentini - 2014.pdf: 3160453 bytes, checksum: bcd4f593c1bbefa247afd83aa66ef627 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-02-27 / Tuberculosis is a disease that affects thousands of people in the World. Although Brazil Health Program had achieved the goal of reducing to 50% the rate of death induced by Tuberculosis, this disease continues to be the second cause of death by infectious disease. One of the main problems to control the disease is the low efficacy of BCG vaccine in protecting young adults. The development of new vaccines that induces long lasting immune response or that stimulate the immunity induced by BCG may improve the control of TB spreading. This study evaluated the use of microstructured liposomes containing HspX with or without MPL or CpG DNA adjuvants as vaccine for tuberculosis. The HspX specific humoral and cellular immune responses were compared between the different vaccine formulations. All vaccines containing liposome microparticules and HspX were immunogenic and antigenic. Vaccines formulated with CpG DNA and HspX induced the strongest humoral and cellular immune responses, mainly by generating IFN- and TNF-by both CD4 and CD8 T cells. HspX and MPL mainly induced CD8 T cell activation and humoral specific responses. After protection efficacy evaluation against Mycobacterium tuberculosis challenge, the vaccine formulation that reduced both lung inflammatory lesions and the bacterial load was the microstructured liposome containing HspX and CPG DNA. These results show for the first time the use of microstructured liposome as adjuvant and delivery system in HspX vaccine formulation for tuberculosis. / A tuberculose é uma doença que acomete milhões de indivíduos no mundo. No Brasil esta doença é a segunda causa de morte por doença infectocontagiosa, embora o País tenha reduzido a metade o numero de mortes por tuberculose. Um dos principais problemas para o controle desta doença é a baixa eficácia da vacina BCG em proteger adultos. O desenvolvimento de novas vacinas que induzam uma resposta imune eficaz e duradoura, ou que estimulem a BCG a aumentar a imunidade já existente é de grande valia. O objetivo desta dissertação foi avaliar e comparar se lipossomas microestruturados contendo HspX em diferentes formulações vacinais, associados ou não a adjuvantes conhecidos: CpG DNA ou MPL poderiam influenciar na resposta imune humoral e celular de camundongos contra o Mycobacterium tuberculosis. Nossos resultados mostram que lipossomas microestruturados contendo HspX foram imunogênicos e antigênicos. As formulações vacinais contendo o adjuvante CpG DNA foram as principais indutoras de resposta humoral e celular específica, principalmente com produção de IFN- e TNF- tanto por linfócitos T CD4+ quanto CD8+. Formulações vacinais contendo HspX e MPL induziram resposta imune humoral e ativaram principalmente linfócitos T CD8. A formulação vacinal que melhor reduziu as lesões pulmonares provocadas pelo Mycobacterium tuberculosis, assim como a carga bacilar foi a composta por lipossomas microestruturados contendo HspX e CpG DNA. Estes resultados demonstram pela primeira vez o uso de lipossomas microestruturados em formulações de vacinas com o antígeno HspX para a tuberculose.

Oximas têm sido extensivamente usadas como antídoto para envenenamento por organofosforados e como desontaminante. Micelas e vesículas, utilizadas como catalisadores e transportadores de drogas, constituem agentes potenciais para tratamento e descontaminação. Neste trabalho descrevemos a reação de p-Nitrofenildifenilfosfato (PNPDPP), um substrato modelo para organofosforado, com: acetofenoxima (I); ácido 10- fenil-10-hidroxiiminodecanóico (II); 4-(9-carboxinonanil)-1-(9-carboxi-1-hidroiimino nonanil) benzeno (III); cloreto de N-dodecilpiridina (IV); cloreto N-metilpiridina 2-aldoxima (V), na presença de micelas catiônicas e zwitteriônicas de cloreto de hexadeciltrimetilamônio, CTAC e N-Hexadecil-N,N-dimetil-1-propano sulfonato, HPS, respectivamente, e vesículas catiônicas de dioctadecildimetilamônio, DODAC. O pKa aparente, pKap, das oximas em agregados de anfifilicos, a constante de velocidade de segunda ordem de oximólise em micelas ou vesículas, km, e as constantes de velocidade observadas para a oximólise de PNPDPP, kobs, foram determinadas espectrofotometricamente, a pH constante, variando-se a concentração dos anfifílicos. Os resultados foram analisados usando as teorias: modelo de pseudofase (PP) e modelo de pseudofase com considerações de troca iônica (PIE), descrita na literatura pelo nosso grupo. As constantes de segunda ordem para oximólise de PNPDPP em água, kox, determinadas foram 6,5 M^-1 min^-1 (I, II e III) e 2,8 M^-1 min^-1 (IV e V). O kobs máximo em micelas e vesículas, kobsmax, e o kobs em água, kw, no mesmo pH, foram utilizadas para calcular o fator de aceleração máxima, AF, para cada anfifílico (AF = kobsmax/kw). Os agregados catalisam a decomposição de PNPDPP e os valores de AF (e km) foram da ordem de 10^4 (32 min^-1), 10^4 (125 min^-1) e 10^6 (80 min^-1) para a reação da oxima IV com CTAC, HPS e DODAC, respectivamente. A análise quantitativa da dependência da concentração de agregados anfifílicos na oximólise mostrou um considerável aumento da constante de velocidade da reação produzido por micelas e vesículas (maior que 8 x 10^6 vezes). Esse efeito é parcialmente devido a: concentração local dos reagentes, efeitos nos pKas dos nucleófilos e, mais importante, mudança na reatividade intrínseca das oximas. / Oximes have been extensively used as antidotes and decontaminants of organophosphates. Micelles and vesicles, catalysts and drug transport agents, constitute potential vehicles for Oxime treatment. Here we describe the reaction of p-nitrophenyldiphenylphosphate (PNPDPP) with: acetophenoxime (I); 10-phenyl-10-hydroxyiminodecanoic acid (II); 4-(9-carboxynonanyl)-1-(9-carboxy-1-hydroyiminononanyl) benzene (III); N-dodecylpyridinium chloride (IV); N-methylpyridinium 2-aldoxime chloride (V), in the presence of cationic and zwitterionic micelles, hexadecyltrimethylammonium chloride, CTAC and N-Hexadecyl-N,N-dimethyl-1-propanesulfate, HPS, respectively, and cationic vesicles of dioctadecyldimethylammonium, DODAC. The apparent pKa, pKap, of the oximes in the amphiphile aggregates, the second order rate constants of oximolysis in micelles and vesicles, km, and the observed rate constants for PNPDPP oximolysis, kobs, were determined spectrophotometrically at constant varying amphiphilic concentrations. The results were analyzed using the pseudo-phase theory (PP) and pseudo-phase / ion exchange (PIE). The second order rate constant for (uncatalyzed) oximolysis of PNPDPP were 6.5 M^-1 min^-1 (I, II and III) and 2.77 M^-1 min^-1 (IV and V). From the maximum value of kobs in micelles and vesicles, kobsmax, and the value of kobs in water, kox, at the same pH, the maximum acceleration factor, AF, were calculated (AF = kobsmax / kw). The amphiphiles catalyzed the oximolysis of PNPDPP and the values of AF (and km) were ca 10^4 (32 min^-1), 10^4 (125 min^-1) and 10^6 (80 min^-1) for the reactions of Oxime IV in CTAC, HPS and DODAC, respectively. Quantitative analysis of the amphiphile concentration-dependence of rates demonstrated that the considerable rate increase produced by micelles and vesicles on the rate of oximolysis (up to 8 x 10^6 fold) is partly due to reagent concentration in the aggregate, effects on the pKas of the nucleophiles and, more importantly, catalysis.

Introduction: Over the past few decades, nanoparticles (NPs) have gained immeasurable interest in the field of drug delivery. Various NP formulations have been disseminated in drug development in an attempt to increase efficacy, safety and tolerability of incorporated drugs. In this context, NP formulations that increase solubility, control release, and/or affect the in vivo disposition of drugs, were developed to improve the pharmacokinetic and pharmacodynamic properties of encapsulated drugs.Areas covered: In this article, important properties related to NP function such as particle size, surface charge and shape are disseminated. Also, the current understanding of how NP characteristics affect particle uptake and targeted delivery is elucidated. Selected NP systems currently used in delivery of drugs in biological systems and their production methods are discussed as well. Emphasis is placed on current NP formulations that are shown to reduce drug-induced adverse renal complications.Expert opinion: Formulation designs utilizing NP-encapsulated drugs offer alternative pharmacotherapy options with improved safety profiles for current and emerging drugs. NPs have been shown to increase the therapeutic index of several entrapped drugs mostly by decreasing drug localization and side effects on organs. Recent studies on NP-encapsulated chemotherapeutic and antibiotic medications show enhanced therapeutic outcomes by altering drug degradation, increasing systemic circulation and/or enhancing cell specific targeting. They may also reduce the distribution of encapsulated drugs into the kidneys and attenuate drug-associated adverse renal complications. The usefulness of NP formulation in reducing the nephrotoxicity of nonsteroidal anti-inflammatory drugs is an underexplored territory that deserves more attention.

We have recently reported that antioxidant liposomes can be used as antidotes for mustard gas induced lung injury in guinea pigs. The maximum protection was achieved with a liposome composed of tocopherols (α, γ, δ) and N-acetylcysteine (NAC) when administered after 5 min of exposure of 2-chloroethyl ethyl sulfide (CEES), a half sulfur mustard gas. We also reported an association of mustard gas-induced lung injury with an activation of MAPK/AP-1 signaling pathway and cell proliferation. The objective of the present study was to investigate whether CEES-induced MAPKs/AP-1 signaling pathway is influenced by antioxidant liposome therapy. A single dose (200 μl) of the antioxidant liposome was administered intratracheally after 5 min of exposure of CEES (0.5 mg/kg). The animals were sacrificed after 1 h and 30 days of CEES exposure. Although the liposome treatment did not have any significant effect on the activation of the MAPKs family (ERK1/2, p38 and JNK1/2), it significantly counteracted the CEES-induced activation of AP-1 transcription factors and corresponding increase in the protein levels of Fos, ATF and Jun family members. The liposome treatment significantly blocked the CEES-induced increase in the protein levels of cyclin D1, a cell cycle protein and PCNA, a cell differentiation marker. Furthermore, it protected lung against CEES-induced inflammation and infiltration of neutrophils, eosinophils and erythrocytes in the alveolar space. This suggests that the protective effect of antioxidant liposome against CEES-induced lung damage is mediated via control of AP-1 signaling.

This dissertation explores the potential of using perfluorocarbon emulsion droplets to add an ultrasound-sensitive element to drug delivery systems. These emulsion droplets may be induced to vaporize with ultrasound; during the rarefactional phase of an ultrasound wave, the pressure around the droplets may fall below the vapor pressure of the liquid forming the emulsion, providing a thermodynamic potential for vaporization. This ultrasound-induced phase change of the emulsion droplet could release therapeutics attached to the droplet surface or aid in drug delivery due to mechanical effects associated with vaporization and expansion, similar to the ability of cavitating bubbles to aid in drug delivery. In contrast to bubbles, stable emulsions can be formed at nano-scale sizes, allowing them to extravasate into tissues and potentially be endocytosed into cells. Perfluorohexane and perfluoropentane were selected to form the emulsions due to their relatively high vapor pressure, low water solubility, and biocompatibility. Acoustic droplet vaporization was explored for its potential to increase ultrasound-induced drug release from liposomes. Liposomes have proven to be versatile and effective drug carriers, but are not inherently responsive to ultrasound. eLiposomes, defined as a liposome with encapsulated emulsion droplets, were developed due to the potential of the expanding vapor phase to disrupt bilayer membranes. The resulting vesicle retains the advantages of liposomes for drug delivery, while adding an ultrasound-sensitive element. eLiposomes were loaded with calcein, a fluorescent molecule, as a model drug in order to quantify ultrasound-mediated drug release compared to release from conventional liposomes. Upon exposure to ultrasound, eLiposomes typically released 3 to 5 times as much of the encapsulated load compared to conventional liposomes, with some eLiposome samples approaching 100% release. Emulsion droplets were also added to the outside of conventional liposomes, but resulted in little to no increase compared to control samples without emulsions. Lastly, in vitro experiments were performed with HeLa cells to explore the ability of emulsion droplets and eLiposomes to deliver calcein inside of cells. Calcein delivery to the cytosol was accomplished, and the emulsion-containing samples demonstrated the ability to aid in endosomal escape.