resumo
We have synthesized luminescent nanoparticles comprising a core of lanthanide complexes and shells of amorphous silica using reverse micelles as nanoreactors. 3-Hydroxypicolinate complexes of Eu(II), Tb(III), and the corresponding heteronuclear complexes have been investigated as the photoactive cores. The size of the silica particles is within the nanometer scale, which, together with the ability for surface biofunctionalization, opens up perspectives for their use in bioapplications. Optical studies of the as-prepared nanoparticles reveal that the luminescence properties of the 3-hydroxypicolinate complexes in the matrices are markedly different from their original features.
palavras-chave
SILICA NANOPARTICLES; REVERSE MICELLES; QUANTUM DOTS; MICROEMULSION; NANOCRYSTALS; PHOSPHORS; SPHERES
categoria
Chemistry; Science & Technology - Other Topics; Materials Science
autores
Iwu, KO; Soares-Santos, PCR; Nogueira, HIS; Carlos, LD; Trindade, T
nossos autores
Helena Isabel Seguro Nogueira
Professor Auxiliar
Luís António Ferreira Martins Dias Carlos
Professor Catedrático
Paula Cristina Ramos Soares e Santos
Técnico Superior
Tito Trindade
Professor CatedráticoProjectos
Nanochemistry of magnetic/luminescent composites for in vitro medical diagnosis applications (PTDC/QUI/67712/2006)
RMNE-UA-National Network of Electron Microscopy (REDE/1509/RME/2005 )
agradecimentos
We are grateful to R. A. S. Ferreira for help with the photoluminescence measurements, to M. A. Martins for some of the SEM images and EDX maps, and to A. V. Girao for assistance on the TEM. This work was funded by Fundacao para a Ciencia e a Tecnologia (FCT) and FEDER (Project PTDC/QUI/67712/2006). P.C.R.S.-S. thanks FCT for the postdoctoral scholarship, SFRH/BPD/14954/2004., We also thank some of the TEM work to REDE/1509/RME/2005 and the team involved in this project.