Methionine - Au Nanoparticle Modified Glassy Carbon Electrode: a Novel Platform for Electrochemical Detection of Hydroquinone

A high sensitive electrochemical sensor based on methionine/gold nanoparticles (MET/AuNPs) modified glassy carbon electrode (GCE) was fabricated for the quantitative detection of hydroquinone (HQ). The as-modified electrode was characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The electrochemical performance of the sensor to HQ was investigated by using cyclic and differential pulse voltammetry, which revealed its excellent electrocatalytic activity and reversibility towards HQ. The separation of anodic and cathodic peak (Delta E-p) was decreased from 471 mV to 75 mV. The anodic peak current achieved under the optimum conditions was linear with the HQ concentration ranging from 8 mu M to 400 mu M with the detection limit 0.12 mu M (3 sigma). The as-fabricated sensor also showed a good selectivity towards HQ without demonstrating interference from other coexisting species. Furthermore, the sensor showed a good performance for HQ detection in environmental water, which suggests its potential practical application.