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Prepara??o de micro/nanopart?culas de poliuretano biodegrad?vel carreadoras de ?leo de a?a? e α tocoferol

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Previous issue date: 2014-03-06 / Searches in nanotechnology allied to studies of biopolymers advances for application in the medical / pharmaceutical field. Micro / nanoparticles (NP) with biodegradable polymer systems are promising for the controlled release of drugs in the form of nanocapsules (NC) or nanospheres (NS), able to protect / release the substance gradually. This work aims to prepare NP polyurethane (Mw = 224,973 g/ mol and Mn = 134 670 g / mol) for the encapsulation by multiple emulsion of the pharmaco α-tocopherol (α-TOC) with and without a?ai oil and different stirring techniques (ultra-turrax (TR) and ultrasound (SM)), as well as the study of controlled release in physiological medium. The average sizes of the obtained NP were between 600 nm and 10 μm using the SM and between 2-15 μm using the TR and all presented spherical morphology and variables distributions depending on the presence or absence of a?ai oil. It was also possible to detect the presence of α-TOC and a?ai oil (when present) in all NP's, as well as the degradation of PU and release of α-TOC through the techniques of UV-Vis, IR and TGA. The encapsulation efficiency of α-TOC was moderate, ranging between 15-34% for NPs obtained by TR and between 18-44% for NPs obtained by SM, due to the affinity of the hydrophobic compound with the PU. The amount of α-TOC initially added in the formulations obtained high rates of recovery ranging from 93-96%. The NPs showed a mass loss of less than 4% when exposed to hydrolytic degradation up to 30 days. The ultraturrax samples without a?ai oil and ultrasound with a?ai oil showed increased release of α-TOC from the 12th day, whereas NP's ultra-turrax with a?ai oil and ultrasound without acai oil showed constant release up to day 30. The results indicate that the presence of oil using the MS showed more efficiency in the formation of NPs / Pesquisas em nanotecnologia aliada aos estudos dos biopol?meros possibilitaram avan?os para aplica??o na ?rea m?dica/farmac?utica. Sistemas de micro/nanopart?culas (NP) com pol?meros biodegrad?veis s?o promissores na libera??o controlada de f?rmacos na forma de nanoc?psulas (NC) ou de nanoesferas (NE), capaz de proteger/liberar a subst?ncia gradativamente. Este trabalho tem como objetivo preparar NP de poliuretano (PU- Mw= 224.973 g/mol e Mn=134.670 g/mol) para o encapsulamento por emuls?o m?ltipla do f?rmaco α-tocoferol (α-TOC) com e sem ?leo de a?a? e com diferentes t?cnicas de agita??o (ultra-turrax (TR) e ultrassom (SM) ), bem como, o estudo de libera??o controlada em meio fisiol?gico. Os tamanhos m?dios das NP obtidas foram entre 600nm e 10 μm utilizando o SM e entre 2-15 μm utilizando o TR e apresentaram morfologia esf?rica e distribui??es vari?veis em fun??o da presen?a ou n?o de ?leo de a?a?. Tamb?m foi poss?vel detectar a presen?a de α-TOC e ?leo de a?a? (quando presente) em todas as NP s, assim como a degrada??o do PU e libera??o do α-TOC atrav?s das t?cnicas de UVVis, TGA e IV. A efici?ncia de encapsulamento do α-TOC foi moderada, variando entre 15 a 34% para as NP s obtidas por TR e entre 18 a 44% para as NP s obtidas por SM, devido ? afinidade deste composto hidrof?bico pelo PU. A quantidade de α- TOC inicialmente adicionada nas formula??es obteve tamb?m elevadas taxas de recupera??o, variando entre 93-96%. As NP s apresentaram uma perda de massa abaixo de 4% quando expostos a degrada??o hidrol?tica at? 30 dias. As amostras TR S/?LEO e SM C/?LEO apresentaram libera??o crescente de α-TOC a partir do 12? dia, enquanto que as NP s TR C/?LEO e SM S/?LEO apresentaram libera??o constante ate 30? dia. Os resultados indicam que a presen?a de ?leo e utiliza??o de SM mostraram-se mais eficiente na forma??o das NP s.

Identiferoai:union.ndltd.org:IBICT/oai:tede2.pucrs.br:tede/3250
Date06 March 2014
CreatorsSantos, Fabiana Gon?alves dos
ContributorsLigabue, Rosane Ang?lica
PublisherPontif?cia Universidade Cat?lica do Rio Grande do Sul, Programa de P?s-Gradua??o em Engenharia e Tecnologia de Materiais, PUCRS, BR, Faculdade de Engenharia
Source SetsIBICT Brazilian ETDs
LanguagePortuguese
Detected LanguageEnglish
Typeinfo:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis
Formatapplication/pdf
Sourcereponame:Biblioteca Digital de Teses e Dissertações da PUC_RS, instname:Pontifícia Universidade Católica do Rio Grande do Sul, instacron:PUC_RS
Rightsinfo:eu-repo/semantics/openAccess
Relation-7432719344215120122, 500, 600, -655770572761439785

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