Heavy metals emit low-energy electrons when exposed to X-rays at specific energies, researchers  have found, which raises the possibility that implants made of gold or platinum could allow doctors to destroy tumors with low-energy electrons, while exposing healthy tissue to far less radiation than is possible today.
 
A prototype device shows that specific X-ray frequencies can free low-energy electrons from heavy-metal nanoparticles.  The researchers' computer simulations suggest that hitting a single gold or platinum atom with a small dose of X-rays at a narrow range of frequencies produces a flood of more than 20 low-energy electrons.

These ejected electrons can kill cancer kills, shredding their DNA, researchers said. So doctors could embed many heavy-metal nanoparticles inside and around tumors, then hit them with a tailored shot of radiation.

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