Mechanistic insights into the electrochemical oxidation of dopamine by cyclic voltammetry

Transition metal oxide based non‐enzymatic electrochemical sensors: An arising approach for the meticulous detection of neurotransmitter biomarkers

“…The principle of electrochemical detection of DA belongs to the redox reaction of DA into dopamine orthoquinone (DAQ) and vice versa involving 2e -/2H + , which generates a current proportional to its concentration (Scheme 1). [5,88,89]…”

Physicochemical and Electrochemical Characterization of Electropolymerized Polydopamine Films: Influence of the Deposition Process

“…In addition, a more homogenous morphology of the deposited films is obtained with less particulate material, facilitating excellent control of the film thickness [ 13 ]. The oxidation of dopamine at different electrode materials under different experimental conditions, such as varying pH values, have been studied [ 18 , 19 , 20 , 21 ]. The first oxidation steps of dopamine follow an ECE (electron–proton–electron transfer) mechanism even in strong acidic conditions [ 21 ].…”

“…Li et al, performed electrochemical quartz microbalance studies and proposed an ECECEE mechanism for the deposition of PDA at dopamine concentrations higher than 0.2 mM and pH values > 3.86, with 5,6-indolequinone as product, which undergoes further oxidation and isomerization processes [ 19 ]. Schindler and Bechtold proposed that the anodic oxidation of dopamine in a pH range of 5.8 to 7 involves formation of a semiquinone radical and subsequent deprotonation [ 18 ] leading to PDA formation. To date, the final PDA structure has not yet been fully elucidated, similar to the chemical route, although Fourier transform infrared spectroscopy (FTIR) studies indicate poly(5,6-indolequinone) with formation of C-O-C chains during the poly(indole)-like electropolymerization [ 22 ].…”

A platinum–nickel bimetallic nanocluster ensemble-on-polyaniline nanofilm for enhanced electrocatalytic oxidation of dopamine

“…Potential CV scans under neutral pH Name., 2012, 00, 1-3 This journal is © The Royal Society of Chemistry 20xx The DP oxidation under applied potential may proceed by the loss of H + from the DP molecule and the formation of dopaminoquinone on the NCs catalyst surface as illustrated by scheme 1 in Figure 4c. 50 (Figure 4a) The surface structure of NCs under operating conditions differs substantially from that characterized ex situ. 51 In pure Pt NCs a broad feature appearing at -0.1V corresponds to the progressive oxidation of Pt through the adsorption of OH on its extended surface 52,53 while the single broad peak at -0.8 V shows the desorption of hydrogen on Pt terrace sites.…”