In the first of two programmes about nanotechnology, Richard Hollingham investigates how a better understanding of the properties of nanoparticles is helping researchers develop novel medical treatments. He talks to Dr Simon Holland and Wendy Knight at GlaxoSmithKline about research into using nanoparticles to deliver therapeutic agents to precise locations in the body. Richard also visits MagForce, a German research company, that's developing a novel therapy using heated nanoparticles of iron oxide to destroy brain cancers.