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

This work introduces an electrochemical sensor fabricated by electropolymerization of a conductive beta-cyclodextrin (beta-CD) polymer onto a reduced graphene oxide (rGO)-decorated screen-printed electrode (SPE). The coated beta-CD polymer had a high supramolecular recognition capability and superior electrical conductivity, which can improve the electrochemical properties of the beta-CD/rGO/SPE electrode. Electrochemical behaviors of ascorbic acid (AA), dopamine (DA), and uric acid (UA) on the beta-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 beta-CD/rGO/SPE electrode can simultaneously detect these three molecules. The linear ranges for AA, DA and UA were 0.2-2 mM, 0.05-50 mu M and 0.08-150 mu M, respectively. The corresponding detection limits were 0.067 mM, 0.017 mu M and 0.026 mu M, 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 beta-CD/rGO/SPE electrode can be a promising electrochemical sensor for electrocatalytic applications. (C) 2016 Elsevier B.V. All rights reserved.