Measuring an electrical current in an organism is pretty straightforward. All you need is an electrode. Measuring the flow of chemicals in cells or live tissue, however, is much more difficult because the molecules diffuse, mix with one another, and interact with their surroundings.
So to help understand biological processes, university researchers have invented a new device, the "chemistrode," that makes it possible to stimulate, record, and analyze molecular signals at high resolution—in terms of precisely when, where, and in what sequence the signals occurred.