University of Washington researchers have illuminated brain tumors by injecting 33-nanometer fluorescent nanoparticles with an attached fluorescent molecule into the bloodstream, safely crossing the blood-brain barrier.

The nanoparticles improved the contrast in both MRI and optical imaging, which is used during surgery. Nano-imaging could also help with early cancer detection.

Current imaging techniques have a maximum resolution of 1 millimeter. Nanoparticles could improve the resolution by a factor of 10 or more, allowing detection of smaller tumors and earlier treatment.