Banca de QUALIFICAÇÃO: PABLO DE ALCANTARA NUNES

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE: PABLO DE ALCANTARA NUNES
DATA: 21/09/2013
HORA: 09:30
LOCAL: Departamento de Química
TÍTULO:

Preparation and characterization of ferrimagnetic systems containing gold nanoparticles and cyclodextrin

PALAVRAS-CHAVES:

magnetite, core-shell, cyclodextrin, gold nanoparticles.

PÁGINAS: 6
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Química Inorgânica
ESPECIALIDADE: Campos de Coordenação
RESUMO:

Nanocomposites containing magnetite (Fe₃O₄ ) nanoparticles have received much research interest due to their promising biomedical applications. In this work, we synthesized ferrimagnetic systems containing gold nanoparticles and cyclodextrin by co-precipitation method: Fe₃O₄NPs/β-CD and Fe₃O₄@AuNPs/β-CD. The XRD patterns of the particles showed a cubic spinel structure of magnetite/maghemite(Fe₃O₄/g-Fe2O3) for both system (without influence of β-CD). The UV-Vis spectra for Fe₃O₄ NPs exhibited only occurred an increasing of baseline due scattering effect, however the Fe₃O₄@AuNPs/β-CD system showed a maximum band at 528 nm assigned to the plasmonic band. The incorporation of β-CD to the Fe₃O₄ NPs was confirmed by FTIR spectra, which showed fingerprint region (1200–900 cm⁻¹ range) from β-CD peaks. Interesting that Fe₃O₄NPs/β-CD system exhibited a suitable shift probably occasioned to the interaction between Fe₃O₄NPs and β-CD suggesting tetrahedral sites formation of bare magnetic nanoparticles at 584 cm⁻¹ that are characteristic absorption of magnetite Fe–O bonds. These results were confirmed by TGA and SEM analisys. Morphologically, Fe₃O₄ NPs suffer interference of β-CD during their nucleation and agglomeration process producing smaller particles confirmed by approaching Sherrer equation.

MEMBROS DA BANCA:
Presidente - 1508806 - WELTER CANTANHEDE DA SILVA
Interno - 778.751.253-91 - FRANCISCO DAS CHAGAS ALVES LIMA - UESPI
Interno - 1714171 - JANILDO LOPES MAGALHAES
Interno - 1167538 - JOSE MACHADO MOITA NETO