Fluorescence-functionalized magnetic nanocomposites as tracking and targeting systems: Their preparation and characterizations

Based on the electrostatic interaction between carboxymethylated chitosan (CMCH) and negatively charged CdTe quantum dots, and the selective crosslinking of CMCH using glutaraldehyde(GA), we demonstrated the formation of Fe3O4/SiO2/CMCH/CdTe microspheres. The dense silicate shells of Fe3O4 nano-particles (NPs) protect the luminescence quenching from Fe3O4 NPs, so the composite microspheres have great fluorescence and emulative magnetism. These multifunctional fluorescence/magnetic microspheres lead to robust and water dispersible nanoparticle colloidosomes, and should be of great importance for diagnostics application and specific biological applications.