Electropolymerization of a conductive β-cyclodextrin polymer on reduced graphene oxide modified screen-printed electrode for simultaneous determination of ascorbic acid, dopamine and uric acid

Abstract

This work introduces an electrochemical sensor fabricated by electropolymerization of a conductive β-cyclodextrin (β-CD) polymer onto a reduced graphene oxide (rGO)-decorated screen-printed electrode (SPE). The coated β-CD polymer had a high supramolecular recognition capability and superior electrical conductivity, which can improve the electrochemical properties of the β-CD/rGO/SPE electrode. Electrochemical behaviors of ascorbic acid (AA), dopamine (DA), and uric acid (UA) on the β-CD/rGO/SPE electrode were investigated by cyclic voltammetry and differential pulse voltammetry. The anodic peaks of these three molecules were separated perfectly at the sensor, indicating that the β-CD/rGO/SPE electrode can simultaneously detect these three molecules. The linear ranges for AA, DA and UA were 0.2–2mM, 0.05–50μM and 0.08–150μM, respectively. The corresponding detection limits were 0.067mM, 0.017μM and 0.026μM, respectively. As a practical application, the proposed sensor was successfully applied to quantify the concentrations of AA, DA and UA in real biological samples. These results demonstrate that this β-CD/rGO/SPE electrode can be a promising electrochemical sensor for electrocatalytic applications.