Electrochemical polymerization of pyrrole in BMIMPF6 ionic liquid and its electrochemical response to dopamine in the presence of ascorbic acid

Polypyrrole (PPy) film modified glassy carbon (GC) electrode was prepared by electrochemical polymerization in 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6) room temperature ionic liquid. The PPy film obtained in ionic liquid adhered on the electrode surface well and the properties of the PPy film have been characterized via UV–vis spectra and scanning electron microscopy (SEM). The electrochemical response of the PPy modified electrodes toward ascorbic acid (AA) and dopamine (DA) was investigated by differential pulse voltammetry (DPV). Well separated anodic peaks were observed at PPy electrode with peak separation (ΔE) of 200 mV at pH 6.2. Compared with PPy electrode prepared in aqueous solution, DA has a higher oxidation currents at the modified electrode prepared in ionic liquid. The oxidation peak potentials and currents were affected by the pH valuation and the film thicknesses.