Electrochemical Properties of Different Carbon‐Fiber Microelectrodes Using Fast‐Scan Cyclic Voltammetry

In this study, fast‐scan cyclic voltammetry (FSCV) was used to compare responses to neurochemicals of various carbon fibers, with different conductivities and carbon precursors. Pitch‐based P‐25 and P‐55 fibers were compared to polyacrylonitrile‐based T‐650 and HM fibers. Highly conductive fibers such as P‐55s or HMs have larger background charging currents than lower conductivity fibers. Using a standard waveform, PAN‐based fibers and less conductive fibers experience faster kinetics. With a more positive switching potential, higher conductivity fibers show faster kinetics for catecholamines and larger oxidation peak currents for anions such as ascorbic acid and 3,4‐dihydroxyphenylacetic acid (DOPAC). Conductivity was found to have the greatest impact on fiber performance, but the nature of its effect depends on the waveform used and the analyte detected.