The effect of channel height and electrode aspect ratio on redox cycling at carbon interdigitated array nanoelectrodes confined in a microchannel.

Redox cycling is a commonly used electrochemical sensing scheme for enhancing faradaic current signals. This effect can be improved by either optimizing electrode geometries or restricting electrochemical reactions within a limited volume. Here, we demonstrate a simple batch fabrication of 1 : 1 aspect ratio carbon interdigitated array nanoelectrodes integrated in a polydimethylsiloxane microchannel that enables current amplification by up to 1116 times. We also examine the factors that influence the effect of redox cycling, including the electrode aspect ratio and channel height, by using experiments and simulations.