Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-10-03T00:21:48Z No. of bitstreams: 1 MayraKerollySalesMonteiro_DISSERT.pdf: 5097719 bytes, checksum: 8a31b93e5438ec081f424997340a4eb4 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-10-09T22:11:42Z (GMT) No. of bitstreams: 1 MayraKerollySalesMonteiro_DISSERT.pdf: 5097719 bytes, checksum: 8a31b93e5438ec081f424997340a4eb4 (MD5) / Made available in DSpace on 2017-10-09T22:11:42Z (GMT). No. of bitstreams: 1 MayraKerollySalesMonteiro_DISSERT.pdf: 5097719 bytes, checksum: 8a31b93e5438ec081f424997340a4eb4 (MD5) Previous issue date: 2017-07-28 / Biofilmes e revestimentos comest?veis s?o camadas finas de materiais biodegrad?veis aplicados sobre produtos alimentares que desempenham um papel importante na sua preserva??o, distribui??o e comercializa??o. A f?cula de mandioca ? um dos melhores candidatos ? prepara??o de revestimentos comest?veis, por ser um pol?mero completamente biodegrad?vel no solo e na ?gua e de f?cil obten??o. No entanto, a f?cula possui limita??es em suas propriedades f?sico-qu?micas quando comparada aos pol?meros sint?ticos. Por sua vez, o melhoramento destas propriedades foi proposto neste estudo a partir da adi??o de 5%, em massa, de argila em rela??o ? massa seca de biopol?mero. A compatibiliza??o superficial da argila com a matriz biopolim?rica foi realizada por modifica??o superficial na presen?a de tr?s tipos de tensoativos (brometo de cetiltrimetil am?nio, dodecil sulfato de s?dio e ?lcool laur?lico etoxilado). O efeito de tr?s modifica??es sequenciais e cumulativas na argila foi caracterizado por Difra??o de Raios X (DRX), Transformada de Fourier por Radia??o Infravermelha (FTIR), Microscopia Eletr?nica de Varredura (MEV), Espectroscopia de Energia Dispersiva de Raios X (EDS), ?ngulo de Contato (AC), Potencial Zeta (ZETA) e An?lise Termogravim?trica (TGA). A argila modificada sinergicamente na presenta dos tr?s tensoativos evidenciou o maior distanciamento basal entre as camadas de silicato, cerca de 10 nm a mais em rela??o ? argila natural. Os filmes de f?cula de mandioca com argila natural e modificada foram caracterizados como bionanocomp?sito intercalado ou esfoliado atrav?s das an?lises de Microscopia de For?a At?mica (AFM), Microscopia ?ptica (MO), DRX, FTIR, MEV e AC. A influ?ncia da argila modificada e da natural na mudan?a das propriedades f?sico-qu?micas dos filmes de f?cula original foi investigada quanto ? permeabilidade ao vapor d??gua, ductibilidade, opacidade, estabilidade t?rmica e solubilidade em ?gua. Por fim, a argila modificada sinergicamente na presenta dos tr?s tensoativos foi o material de refor?o que mais contribuiu para o melhoramento das propriedades f?sico-qu?micas do filme de f?cula controle, dentre as quais reduziu 90,6% da permeabilidade ao vapor d??gua, bem como 77,43% da dissolu??o m?xima. / Biofilms and edible coatings are thin layers of biodegradable materials applied to food products that play an important role in their preservation, distribution and commercialization. Cassava starch is one of the best candidates for the preparation of edible coatings, because it is a completely biodegradable polymer in soil and water and easy to obtain. However, the starch has limitations in its physical-chemical properties when compared to the synthetic polymers. In turn, the improvement of these properties was proposed in this research from the addition of 5%, by mass, of clay in relation to the dry mass of biopolymer. The surface compatibilization of the clay with the biopolymer matrix was performed by surface modification in the presence of three types of surfactants (cetyltrimethyl ammonium bromide, sodium dodecyl sulfate and ethoxylated lauryl alcohol). The effect of three sequential modifications on the clay was characterized by X-ray Diffraction (XRD), Fourier Transform by Infrared Radiation (FTIR), Scanning Electron Microscopy (SEM), Dispersive Lightning Spectroscopy (DLS), Contact Angle (AC), Zeta Potential (ZETA) and Thermogravimetric Analysis (TGA). The clay modified synergistically in the presence of the three surfactants showed the greatest basal space between the silicate layers, about 10 nm more than the natural clay. The cassava starch films with natural and modified clay were characterized as bionanocomposite intercalated or exfoliated through Atomic Force Microscopy (AFM), Optical Microscopy (MO), XRD, FTIR, SEM and AC analyzes. The influence of modified and natural clay on the change in the physical-chemical properties of the original starch films was investigated for water vapor permeability, ductility, opacity, thermal stability and water solubility. Finally, the synergistically modified clay in the presence of the three surfactants was the reinforcing material that contributed the most to the physical-chemical properties of the control starch film, among which it reduced the permeability to water vapor by 90.6%, as well as 77.43% of the maximum dissolution.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-23T19:49:19Z No. of bitstreams: 1 EdianaPaulaRebitski_DISSERT.pdf: 5282849 bytes, checksum: f1a7a2f4009a400f77db6f24d30a9596 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-27T19:26:26Z (GMT) No. of bitstreams: 1 EdianaPaulaRebitski_DISSERT.pdf: 5282849 bytes, checksum: f1a7a2f4009a400f77db6f24d30a9596 (MD5) / Made available in DSpace on 2016-06-27T19:26:26Z (GMT). No. of bitstreams: 1 EdianaPaulaRebitski_DISSERT.pdf: 5282849 bytes, checksum: f1a7a2f4009a400f77db6f24d30a9596 (MD5) Previous issue date: 2015-05-22 / Bionanocomp?sitos s?o materiais nanoestruturados h?bridos org?nico-inorg?nico que envolvem uma contrapartida org?nica de origem biol?gica, por exemplo, um biopol?mero, associado a um s?lido inorg?nico em nanoescala. Materiais bioh?bridos a base de argilominerais (montmorillonita, sepiolita) e s?lidos inorg?nicos (hidr?xidos duplos lamelares) s?o uma boa op??o para diversas aplica??es (tais como biom?dicas) devido ao seu baixo custo, biodegradabilidade e biocompatibilidade. Devido a capacidade de troca i?nica, ?rea espec?fica elevada e a capacidade de adsor??o que esses materiais possuem, ? poss?vel combinar uma grande variedade de esp?cies org?nicas, tais como drogas, na qualidade de transportadoras. Neste contexto, este trabalho apresenta a prepara??o de novos bionanocomp?sitos com base na combina??o dos biopol?meros carboximetilcelulose e ze?na como revestimento do h?brido, argilomineral - antibi?tico e hidr?xidos duplos lamelares-antibi?tico. Para a s?ntese dos materiais bioh?bridos foi utilizado o antibi?tico neomicina de uso t?pico e amoxicilina de uso oral como f?rmacos modelos, o qual, foram incorporados nos argilominerais e hidr?xidos duplos lamelares por processo de intercala??o por troca i?nica e por adsor??o. / Bionanocomposites systems clay base (montmorillonite and sepiolite), layered double hidroxides and biopolymers (carboxymethylcellulose and zein) were evaluated as topical delivery systems with antibacterial activity and as oral delivery systems. For this study, neomycin, a topical antibiotic, indicated mainly for open wound infections. The drug amoxicillin, an antibiotic indicated mainly for throat infections, were also used in this study. Both antibiotics were used as model drugs. Initially, drugs were incorporated directly into the biopolymer matrix, comprising the combination of carboxymethylcellulos and zein, being conformed as movies and balls and evaluated for their antibacterial activity and controlled release simulating gastrointestinal fluids. Moreover, hybrids materials have been prepared where the neomycin drug was incorporated into the lamellar inorganic solids, such as montmorillonite by ion exchange reaction, and the fibrous type, such as sepiolite by adsorption in aqueous solution. But the drug amoxicillin was incorporated into layered double hydroxides by anion exchange and montmorillonite by cation exchange. The resulting hybrids were in turn combined with the biopolymer matrix yielding bionanocomposites shaped materials such as films were tested for their antibacterial activity, and the shaped materials beads were tested for their release in the gastrointestinal fluids. Through the analysis of various physico-chemical techniques, we observed the interactions between the studied materials, the formation of hybrids materials, obtaining the bionanocomposites materials and material efficiency when applied in controlled release of drugs both topical and use oral mainly influenced by the presence of zein, are promising as topical delivery systems and oral drugs.