Nafion/polyaniline/Zeolitic Imidazolate Framework-8 nanocomposite sensor for the electrochemical determination of dopamine

A novel Nafion/polyaniline/Zeolitic Imidazolate Framework-8 nanocomposite (Nafion/PANI/ZIF-8) has been fabricated on the surface of glassy carbon electrode (GCE) for the electrochemical determination of dopamine (DA). In this sensor, ZIF-8 provides large surface area and excellent electrocatalytic activity while PANI exhibits great electric conductivity. Surface morphology and structure of the modified electrode were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The eletrocatalytic properties of the modified electrode were investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The Nafion/PANI/ZIF-8 modified electrode displayed a high catalytic performance towards DA oxidation in PBS, which can be attributed to the synergistic effects of PANI and ZIF-8. Under the optimized conditions, the linear range was from 1.0 x 10(-7) to 1.0 x 10(-4) mol L-1 and the limit of detection was 1.2 x 10(-8) mol L-1. In addition, the developed sensor showed great selectivity, high reproducibility, excellent stability and applicability in real samples analysis.