PEDOT Electrodes for Improving Multiple Facets of Neurochemical Measurements

Abstract

In this dissertation, several new tools for making neurochemical measurements are presented. All of the technologies developed here include the conducting polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), as a sensing platform. PEDOT is ideal for inclusion in neurochemical sensors because it is inexpensive, easily processed and patterned, biocompatible, and, conductive. A synthesis of low-capacitance PEDOT:Tosylate enables electrochemical measurements of neurotransmitters with scan rates of 100 V/s. This material was further characterized to determine the unique molecular properties that lead to outstanding electrochemical performance for the measurement of neurotransmitters. Using this new information a coating method was developed to coat platinum microelectrodes with PEDOT:Perchlorate capable of making fast-scan cyclic voltammetry measurements of a variety of neurotransmitters. During this process, we serendipitously discovered a novel polymerization chemistry to make PEDOT in the absence of an oxidant or catalyst. One of the products of this synthesis was used to create a polymer blend PEDOT:Nafion nanoparticle for the quantitation of trace water in organic solvents. Lastly, we created a microfluidic device capable of measuring exocytosis events from single cells at single PEDOT:Tosylate microelectrodes. Together these advances result in an expansion to the available tools for studying neurochemical release events in the brain and the understanding of electrochemistry at conducting polymers.