Electrochemical sensing of glucose by reduced graphene oxide-zinc ferrospinels

Highlights: • A facile in situ hydrothermal method for ZnFe₂O₄ nanoparticles incorporation into graphene oxide sheets. • Excellent selectivity, reproducibility and stability properties compared to others Zn-based glucose sensor. • Amount of reduced graphene oxide directly affected the electro-catalytic activity of ZnFe₂O₄/rGO nanocomposite towards glucose detection. - Abstract: We have developed ZnFe₂O₄ magnetic nanoparticles/reduced graphene oxide nanosheets modified glassy carbon (ZnFe₂O₄/rGO/GCE) electrode as a novel system for the electrochemical glucose sensing. Via a facile in situ hydrothermal route, the reduction of GO and the formation of ZnFe₂O₄ nanoparticles occurred simultaneously. This enables the ZnFe₂O₄ nanoparticles dispersed on the reduced graphene sheet. Characterization of nanocomposite by X-ray diffraction (XRD) and transmission electron microscopy (TEM) clearly demonstrate the successful attachment of ZnFe₂O₄ nanoparticles to graphene sheets. Electrochemical studies revealed that the ZnFe₂O₄/rGO/GCE possess excellent electrocatalytic activities toward the oxidation of glucose and the performance of sensor is enhanced by integration of graphene nanosheets with ZnFe₂O₄ nanoparticles.