Modification of glassy carbon electrode with poly-melamine film: An application for the detection of hydroquinone, catechol and resorcinol

Abstract

In this study, we share findings about the development of a sensor using poly-melamine modified glassy carbon electrode (PMel/GCE) that is capable of detecting dihydroxybenzene isomers simultaneously in aqueous solution. We prepared poly-melamine film by electro-polymerization on GCE in acidic solution containing melamine monomer, then it was characterized by field emission scanning electron microscopy (FE-SEM), electrochemical impedance spectroscopy (EIS). Cyclic voltammetry (CV) shows the electrochemical behaviors of dihydroxybenzene isomers at the PMel/GCE. Square wave voltammetry (SWV) was used for the simultaneous determination of dihydroxybenzene isomers. The two broad anodic peaks of dihydroxybenzene isomers at 0.380 V for hydroquinone and catechol and 0.712 V for resorcinol on the bare GCE resolved in three well-defined peaks at 0.084 V for hydroquinone, 0.184 V for catechol and 0.608 V for resorcinol vs. Ag/AgCl, respectively. It exhibited a good linearity to dihydroxybenzene isomers in the concentration range of 5-300 µM for hydroquinone, 5-500 µM for catechol and 3-200 µM for resorcinol with good sensitivity of 0.052, 0.055 and 0.038 µA/µM. And the detection limits were 0.65, 1.90 and 0.58 µM at a signal-to-noise ratio of 3. Furthermore, this sensor is expected to be utilized in detecting these isomers in local tap water sample with good anti-interference.