Silica-coated iron oxide yield versatile nanoparticles for biomedicine

(Nanowerk News) By melding magnetic and luminescent properties with an easily modified surface, a team of investigators at the National Research Council of Canada have created what could prove to be a highly versatile nanoparticle system for imaging and delivering drugs to tumors. Initial studies with this new nanoparticle system are reported in the journalChemistry of Materials ("Multifunctional Nano-Architecture for Biomedical Applications").
Benoit Simard, Ph.D., and his colleagues started their nanoscale platform development effort with standard iron oxide nanoparticles. They then coated these particles with a layer of silica, and added a second layer of silica that also contained a fluorescent dye.
The net effect of adding these layers was three-fold. First, doubly coating the iron oxide nanoparticles improved the magnetic properties of the standard uncoated particles. Second, trapping the fluorescent dye in the second silica layer increased the stability of the dye when irradiated with bright light. Finally, the second silica layer provided a surface to which targeting and drug molecules could be attached easily.
Source: National Cancer Institute