Dextran and PEG Coating Reduced Nanoparticle Toxicity to Cells

Iron oxide nanoparticles are of interest for drug delivery, since they can be targeted using a magnetic field. However, prior to using nanoparticles in vivo, they must be shown as relatively non-toxic to cells. We and others have shown that bare iron oxide nanoparticles are readily taken up by cells, where they catalyze production of highly toxic reactive oxygen species (ROS). This oxidative stress disrupts the cell cytoskeleton and alters cell mechanics. [1] Iron oxide nanoparticles under current development for in vivo biomedical applications are often coated with a polysaccharide (eg. dextran) or a polymer (eg. polyethylene glycol, PEG). Both the size and the surface coating of nanoparticle may play an important role in cell toxicity.