MTorrice writes: "A beam of electrons can pick up and carry nanoparticles, according to a new study. The so-called electronic tweezers could help scientists in diverse tasks, such as building up new materials nanoparticle by nanoparticle, and measuring the forces between nanoparticles and living cells, the researchers say. In the past, scientists have manipulated microsized particles, including single cells, using a beam of laser light called optical tweezers. But the force required to trap a particle with optical tweezers increases as the particle gets smaller, making grappling with nanoparticles difficult. Researchers at Lawrence Berkeley National Laboratory developed an alternative to optical tweezers by modifying a transmission electron microscope, which produces images by passing a stream of electrons through a sample."