RuO 2 /rGO heterostructures as mimic peroxidases for colorimetric detection of glucose

The successful synthesis of ruthenium oxide/reduced graphene oxide (RuO 2 /rGO) heterostructures by one-pot hydrothermal method using graphene oxides and RuCl 3 as precursors is reported. The heterostructures had high peroxidase-like (POD-like) activities, which catalyzes the oxidation of classical peroxidase substrate 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of H 2 O 2 to create a blue colored reaction product. The catalytic activity was significantly enhanced by the synergistic effect between RuO 2 nanoparticles and rGO. RuO 2 /rGO had a low K m of 0.068 mM and a high v max of 1.228 × 10 −7 M·s −1 towards TMB in the TMB-H 2 O 2 catalytic oxidation system. In addition, the POD-like activity originating from the electron transfer mechanism was confirmed by cytochrome C (Cyt C) oxidation experiment. A colorimetric method based on RuO 2 /rGO heterostructures was developed with good sensitivity and selectivity for glucose detection with a limit of detection of 3.34 μM and a linear range of 0–1500 μM. The RuO 2 /rGO heterostructures have potential applications in the biomedical areas, such as biosensor and diagnostics. Graphical abstract