Multifunctional magnetic/upconversion luminescent mesoparticles, consisting of a Fe(3)O(4) nanoparticle core and a LaF(3):Yb(3+), Er(3+) nanocrystal shell, have been developed using a facile co-precipitation approach. Owing to their excellent superparamagnetic properties, superior T(2)-enhanced magnetic resonance effect and strong upconversion emissions, the as-formed mesoparticles have great potential in diverse medical diagnostics and biological imaging.
