Nanocoax-based electrochemical sensor.

We have used a facile polymer imprint process to fabricate a three-dimensional electrochemical nanosensor, the sensitivity of which is two decades higher than that of planar controls. The device is composed of an array of vertically oriented nanoscale coaxial electrodes, with the coax cores and shields serving as integrated working and counter electrodes, respectively, each with a nanoscale separation gap (coax annulus width). Arrays of ~10(6) devices per square millimeter were prepared with different gaps, with smaller gaps yielding higher sensitivity.