Attack of the nanoparticles

MIT scientists have developed nanoparticles that, when pulsed with an electromagnetic field, release drugs to attack tumours. The development could lead to the improved diagnosis and targeted treatment of cancer.

The team of reserchers, led by Sangeeta Bhatia from MIT's Department of Electrical Engineering and Computer Science, had previously developed injectable nanoparticles that can flow through the bloodstream, find a home in a tumour and then clump together. The tumour can then be visualised through Magnetic Resonance Imaging (MRI).

The team then realised that they could tether drugs to the nanoparticles using strands of DNA, a classical heat sensitive material. Because the nanoparticles are superparamagnetic, when they are exposed to a low-frequency electromagnetic field, they radiate heat that breaks the tethers and releases the drugs.

The waves in the magnetic field have frequencies between 350 and 400kHz - the same range as radio waves, which pass harmlessly through the body and heat only the nanoparticles.