3-D Carbon Interdigitated Array Nanoelectrodes for Highly Sensitive Sensing of Neurotransmitters

Abstract

We introduce a highly sensitive electrochemical sensor amplifying current signals by cycling redox species between fingers of carbon interdigitated array (IDA) nanoelectrodes of which aspect ratios are deliberately controlled through carbon-MEMS process which consists of a conventional photolithography step followed by pyrolysis converting photoresist patterns into 3-D glassy carbon electrodes. The effect of the electrode geometry on the current signal amplification was studied using cyclic voltammetry and further signal amplification was achieved using metal electrodeposition on the carbon electrodes. The feasibility of carbon IDA nanoelectrodes as a highly sensitive sensor for the neurotransmitters was demonstrated by measuring redox current of dopamine in a buffer solution.