Iron-laden nanoparticles make non-toxic stem cell labels for magnetic resonance imaging. Imaging agents are used to enhance the resolution in magnetic resonance imaging (MRI), which allows internal structure of the body to be visualised. Xiaoyuan Chen at the National Institute of Health, Bethesda, has modified iron-oxide nanoparticles to make non-toxic and more efficient imaging agents. The iron nanoparticles can enter cells without killing them Iron oxide has been used for cell labelling before but transfection agents are needed to aid uptake into cells. This can make them toxic and result in cell death, particularly in sensitive cell lines such as stem...
