Environmental sensors and handheld devices that quickly and easily detect and identify individual viruses would provide early warning of infections in individuals, the spread of disease in populations, and biological weapons attacks.

Harvard University researchers led by Charles Lieber, a professor of chemistry, have built a detector from nanowire transistors that can identify individual virus particles in real time in unpurified samples. The prototype uses antibody proteins attached to the nanowires to briefly capture individual virus particles.

“The binding causes a change in the current of the nanowire-based electronic device, which signals the virus presence,” said Lieber.