Graphene-Loaded Nanofiber-Modified Electrode: A Novel and Sensitive Electrochemical Detection System

摘要

A novel electrode based on graphene/polyaniline/ polystyrene (G/PANI/PS) nanofibers has been prepared via electrospinning for the determination of biomolecule (i.e. dopamine) and heavy metals (i.e. Cd~(2+) and Pb~(2+)). The factors affecting the electrochemical sensitivity and morphology of G/PANI/PS nanofibers, such as percentage of G loading (%G), electrospinning time, type of organic solvent and concentration of polymer were investigated and optimized. The obtained nanofibers were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and cyclic voltammetry (CV). The G/PANI/PS nanofiber-modified electrodes were used for selective and sensitive determination of dopamine. A very low limit of detection (LOD: 0.05 nM) and limit of quantification (LOQ: 0.30 nM) were achieved for dopamine. Furthermore, these modified electrodes were successfully applied for sensitive and simultaneous determination of Cd~(2+) and Pb~(2+).