A novel electrochemiluminescence sensor based on Ru(bpy)32+ immobilized by graphene on glassy carbon electrode surface via in situ wet-chemical reaction

A facile, low-cost and effective electrochemiluminescence (ECL) sensor based on Ru(bpy)32+ immobilized by graphene film without any auxiliary medium had been developed for the first time. The graphene film was directly formed on a glassy carbon electrode surface via an in situ wet-chemical reduction of graphene oxide (GO). It had fast electron-transfer rate and excellent stability for immobilizing Ru(bpy)32+ via π–π interaction. The cyclic voltammetry result indicated that the ECL sensor had high electrochemical activity. Moreover, ECL behaviors of this sensor were investigated in details using tripropylamine as the model. And the experimental results indicated that the sensor had excellent ECL efficiency and long-term stability. Furthermore, the sensor was successfully applied to detect oxalate in urine samples with high selectivity, sensitivity and reliability, which suggested the ECL sensor could be applicable for real sample analysis.