Dopamine Electrochemical Sensor Based on Molecularly Imprinted Polymer on Carbon Electrodes with Platinum Nanoparticles

This article addresses the construction of a dopamine electrochemical sensor based on a molecularly imprinted polymer on carbon electrodes, for instance, glassy carbon and highly oriented pyrolytic graphite electrodes with the orientation of edge and basal plane by the formation of thiophene acetic acid-dopamine thin film using electropolymerization. The electrochemical deposition of Pt nanoparticles was then carried out at the modified electrode surface, followed by the extraction of dopamine as a template molecule from the generated layer was performed via elution brought on by chemicals. The variables that affect the performance of the imprinted polymer-based sensor, such as monomer-template ratio, immersion time, and the number of electropolymerization cycles, were examined and optimized. To confirm the changes in the oxidation peak current of DA and to investigate the electrochemical behavior of the MIP sensor, cyclic voltammetry, chronoamperometry, and differential pulse voltammetry (DPV) tests were performed. The differential pulse voltammetry studies revealed that, under ideal circumstances, the limit of detection values of the proposed MIP sensor decorated with Pt nanoparticles was found to be 14.40 nmol L⁻¹, 42.50 nmol L⁻¹, and 0.671 μmol L⁻¹ for glassy carbon, edge, and basal plane electrodes, respectively. In the presence of interferents with comparable structural chemicals, such as ascorbic acid, uric acid, glucose, o-phenylenediamine, and glycine, the proposed sensor exhibits noticeable selectivity. Dopamine analysis in a human fluid such as blood serum was conducted with success using the devised sensor, which was shown to possess impressive stability and reproducibility.

Graphical Abstract