Alloy-structured Au-Co bimetallic nanoparticles-decorated graphene oxide as an efficient electrochemiluminescence sensing platform for sensitive detection of glucose in human serum

Abstract Herein, we present the synthesis and electrochemiluminescence (ECL) sensing applications of the Au-Co/GO nanocomposite. Au-Co/GO nanocomposite was prepared for the first time by decorating graphene oxide (GO) with alloy-structured Au-Co bimetallic nanoparticles (BNPs) via one-step on site chemical reduction. The obtained nanocomposite was comprehensively characterized and the results showed that alloy-structured Au-Co nanoparticles (NPs) have an average size of 4 nm and are highly dispersed on GO layers. ECL measurement revealed that the as-synthesized Au-Co/GO nanocomposite displays a synergistic effect of the GO and the Au-Co BNPs on luminol-H 2 O 2 ECL signal. Further immobilization of glucose oxidase (GOD) onto the Au-Co/GO modified electrode afforded a effective ECL glucose sensor which displayed a dynamic range of 1–100 µM with a satisfactory detection limit of 0.18 μM. Furthermore, the developed enzymatic sensors were successfully applied for monitoring glucose in real human samples.