Roland Piquepaille writes "Radiotherapy is widely used to fight cancers. Today, only beta particles are approved by health regulators, such as the U.S. FDA. Beta particles are small and travel fast, but it takes thousands of them to kill a cancer cell. Now, U.S. researchers have found a way to use alpha particles to destroy cancer tumors by encapsulating them inside carbon nanotubes. These alpha particles, which are 4,000 times bigger than beta particles, are much slower but are more efficient. According to the researchers, 'cancer cells can be destroyed with just one direct hit from an alpha particle on a cell nucleus.' But major issues need to be overcome before future treatments become possible by using them. Read more for additional details and a picture showing how the alpha particles could be packaged inside carbon nanotubes to destroy cancerous cells."