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

Abstract

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.

Electrode Kinetics and Sensitivity of Nanostructured Electrodes from Different Carbon Fiber Precursor Materials

“…DA sensitivity at PAN electrodes correlates inversely with electrical conductivity and tensile modulus of the two types of PAN materials (Table 1 and 4), in agreement with a previous report [18]. However, although Pitch P25 has higher electrical conductivity, sensitivity of DA is …”

“…Analytical response of carbon fiber electrodes has been related to tensile modulus of the fibers [17], in agreement with the direct relationship between carbon fiber tensile modulus and electrical conductivity [16]. It has been reported that sensitivity of cylindrical carbon fiber electrodes to cationic catecholamines correlates with fiber conductivity, but not with the precursor material of the fiber [18]. However, the method of carbon fiber electrode surface fabrication may have contributed to the observed behavior [18].…”

“…It has been reported that sensitivity of cylindrical carbon fiber electrodes to cationic catecholamines correlates with fiber conductivity, but not with the precursor material of the fiber [18]. However, the method of carbon fiber electrode surface fabrication may have contributed to the observed behavior [18]. Carbon fibers from different precursor materials have different surface chemistry and structure.…”

The mechanism of electrically stimulated adenosine release varies by brain region

“…Electrodes Fifty-micrometer-long cylindrical carbon-fiber microelectrodes were made from T-650 carbon fibers (Cytec Engineering Materials, West Patterson, NJ) as described previously [18]. Fast-scan cyclic voltammograms were collected using a Chem-Clamp potentiostat (Dagan, Minneapolis, MN), using data acquisition software and hardware as described previously [7].…”

Automated algorithm for measurement of spontaneous adenosine transients in large electrochemical data sets

“…The Dale group developed a three enzyme biosensor for the detection of adenosine 20 . It works by breaking down adenosine to inosine via adenosine deaminase, subsequently to hypoxanthine via purine nucleoside phosphorylase, finally to xanthine, urate, and hydrogen peroxide via xanthine oxidase.…”