Neumeier, Manuel; Hails, Lauren A.; Davis, Sean A.; Mann, Stephen; Epple, Matthias:

"Synthesis of fluorescent core-shell hydroxyapatite nanoparticles"

In: Journal of Materials Chemistry, Jg. Band 4 (2011) ; Nr. 21, S. 1250-1254
ISSN: 0959-9428
Zeitschriftenaufsatz / Fach: Chemie
Lanthanide-doped fluorescent hydroxyapatite/silica core–shell nanorods, 50–100 nm in length and 30 nm in width, were prepared by precipitation of calcium phosphate in the presence of Eu3+ and Y3+ ions at 60 °C, followed by hydrothermally enhanced crystallization, stabilization with poly(ethyleneimine), and reaction with tetraethyl orthosilicate. The fluorescence intensity of the Eu3+-doped hydroxyapatite nanorods was enhanced threefold by co-doping with Y3+ and doubled after hydrothermal treatment. Significantly, fluorescence quenching by water was reduced in the presence of the thin silica nanoshell to give a further doubling of the fluorescence intensity compared with lanthanide-doped hydroxyapatite nanoparticles prepared in the absence of tetraethyl orthosilicate. Our results suggest that a combination of lanthanide doping, controlled crystallization and core–shell fabrication is a promising route to the preparation of biocompatible calcium phosphate nanoparticles with enhanced fluorescence for potential use in biomedical applications.