Electrochemical Sensing of Isoproterenol using Graphite Screen-printed Electrode Modified with Graphene Quantum Dots

The graphene quantum dots (GQDs) were prepared by tuning the carbonization degree of citric acid and graphite screen-printed electrode modified with graphene quantum dots (GQDs/SPE) was constructed and used for the sensitive voltammetric determination of isoproterenol. In comparison with unmodified electrode, the presence of the GQD/ SPE resulted in a remarkable increase in the peak currents. The electrochemical response characteristics of the modified electrode toward isoproterenol were studied by means of cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry. It was demonstrated that the modified electrode presents good electrical conductivity and has favorable electrochemical response to isoproterenol. The (GQDs/SPE) displays a linear range from 1.0 to 900.0 μM and a detection limit of 0.6 μM (S/N=3) to isoproterenol