Cell biologists use microelectrodes to study the real-time biochemistry of cell-to-cell signaling, factor secretion, and other extracellular events. But when it comes to the kinetics of intracellular biochemistry, much smaller electrodes are needed. So Michael Mirkin of the City University of New York, Queens College and colleagues at Université Pierre et Marie Curie have reduced them to nanoscale sizes.
Specifically, they have made nanoelectrodes that are coated with platinum black—a high-surface-area version of platinum used on larger-size electrodes for detecting reactive oxygen and nitrogen species.
Downsizing microelectrodes might sound straightforward, but it is far from simple, says Adrian Michael of the University of Pittsburgh, who was not involved in the study. “What the paper shows is that to do it well you have to do it very carefully and incorporate things like the atomic force microscope so you can watch what you’re doing,” he says.
Mirkin used the microscope to ...
