Live bacteria (faint dark streaks) are directed down a narrow channel to a pair of electrodes where they are trapped by mild electric currents. The bacteria, in effect, become "bio-junctions" and can be captured, interrogated and released at will. The use of living microbes in such a technology could form the basis for new ways of assembling nanodevices of all kinds. One potential application is as a real-time bio-sensor that could be used in public places to instantly detect and characterize the microbes that might be used in a bio-terror attack.

Credit: The Hamers Group/University of Wisconsin, Madison