Hybrid virus-nanoparticle memory device

No one wants to get a computer virus, but what about a computer made with viruses? Researchers in California created the key switching component in a nanoscale digital memory device (shown) by attaching platinum nanoparticles (silver spheres) to a tobacco mosaic virus (red tube), which they report in the first issue of the journal Nature Nanotechnology (2006, 1, 72). The team, led by Yang Yang of the University of California, Los Angeles, and Cengiz S. Ozkan of the University of California, Riverside, embedded the hybrid bionano switch into a polymer and then sandwiched the system between two metal electrodes (silver bars). When the researchers applied an electrical potential, they noted a marked increase in current at 3 V, indicating that the device was switched on. Presumably this happens because electrons are able to tunnel between the nanoparticles (yellow arrows) at that voltage. When the voltage drops below -2.4 V, the device switches off. The work could lead to nanoscale electronic devices based on biological structures, the authors say.