Simple flame etching of pencil electrode for dopamine oxidation in presence of ascorbic acid and uric acid

Edge and Basal Plane Anisotropy of a Preanodized Pencil Graphite Electrode Surface Revealed Using Scanning Electrochemical Microscopy and Electrocatalytic Dopamine Oxidation as a Molecular Probe

“…This value is relatively lower than those of several graphitic carbon electrodes chemically modified by metals and polymers (Supporting Information, Table S1). ,,− These observations highlight that the PGE* is a good choice for DA sensor application without any other fouling characteristics, unlike conventional HOPG and graphitic carbon-based electrode systems. , Further, the effect of interfering electroactive species was tested using the CA technique by spiking 5 μM DA along with the most common interfering analytes such as ascorbic acid (Asc), uric acid (UA), glucose (Glu), and cysteine (CySH) at E app = 0.2 V vs Ag/AgCl in pH 7 PBS (Figure E). There was no marked alteration in the CA current signal, depicting the appreciable selective electrochemical electroanalytical performance of the PGE*.…”

“…In this connection, ultralow-cost and ready-to-use pencil graphite electrodes, which are composed of ∼85% of graphite, 10% of clay, and 5% of wax-binder, have been referred for electroanalytical applications . Besides, the native form of the PGE is electro-inactive and requires specific surface treatments like preanodization, − thermal treatment, flame itching, and metal/metal oxide − and conducting polymer-based surface − modification procedures for the activation. Unlike the HOPG-based systems, molecular insights into the PGE surface and its activation process were not reported until date.…”

Surface-Activated Pencil Graphite Electrode for Dopamine Sensor Applications: A Critical Review

“…However, the preparation of bulk and reproducible sensor seems to be a challenging task in the above case. In 2017, Chandra et al proposed a distinct flame itch-based surface activation method of PGE for electrochemical DPV sensing of DA [ 50 ]. The flame itching technique was carried out by exposing the PGE in flame (match stick) for a time period of 10–15 s, which resulted in a random re-alteration/carbonization of organic binders on the surface and the formation of carbon–oxygen bonds.…”