Made available in DSpace on 2014-12-17T15:41:55Z (GMT). No. of bitstreams: 1
IdyllaST_DISSERT.pdf: 1649846 bytes, checksum: b16782ef605bdc7a1d3225b281a6f2b3 (MD5)
Previous issue date: 2011-11-08 / Chitosan nanoparticles have been used in several systems for the controlled release of
drugs. The aim of this study was to obtain and characterize chitosan nanoparticles prepared by
the method of coacervation / precipitation using sodium sulfate at different concentrations as
the crosslinking agent. The characterization was done using zeta potential and small angle Xray
scattering, SAXS. The dispersions of chitosan were obtained at pH 1 and pH = 3. The
results of zeta potential at pH = 1 ranged from +64.8 to +29.27 mV and for pH = 3 they varied
from +72.4 to +23.48 mV, indicating that the chain of chitosan is positively charged in acidic
pH and the behavior of nanoparticles in terms of surface charge was independent of pH.
However, the results indicated a dependence of particle size in relation to pH. This difference
in behavior was explained by the influence of enthalpic and entropic components / Nanopart?culas de quitosana t?m sido utilizadas em v?rios sistemas destinados a
libera??o controlada de f?rmacos. O objetivo desse trabalho foi a obten??o e caracteriza??o de
nanopart?culas de quitosana atrav?s do m?todo de coacerva??o/precipita??o utilizando o
sulfato de s?dio em diferentes concentra??es como agente reticulante. A caracteriza??o foi
feita utilizando potencial zeta e espalhamento de pequenos ?ngulos, SAXS. As dispers?es de
quitosana foram obtidas a pH=1 e pH=3. Os resultados do potencial zeta variaram no pH = 1
de +64,8 a +29,27 mV e no pH = 3 de +72,4 a +23,48 mV, indicando que a cadeia de
quitosana fica carregada positivamente em pH ?cido e que comportamento das nanopart?culas
em termos de carga superficial foi independente do pH. Entretanto, os resultados indicaram
depend?ncia do tamanho de part?cula em rela??o ao pH. Essa diferen?a em termos de
comportamento foi explicada pela influ?ncia dos componentes ent?lpicos e entr?picos
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17651 |
| Date | 08 November 2011 |
| Creators | Tavares, Idylla Silva |
| Contributors | CPF:90623207753, http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4788562T6, Wanderley Neto, Alcides de Oliveira, CPF:00738841463, http://lattes.cnpq.br/4789528535524269, Oliveira, Jo?o Bosco Lucena de, CPF:19127537404, http://lattes.cnpq.br/1360004695124740, Muniz, Cl?udia Alves de Sousa, CPF:80693628472, Fonseca, Jos? Luis Cardozo |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Qu?mica, UFRN, BR, F?sico-Qu?mica; Qu?mica |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
Page generated in 0.0028 seconds