Ag–Pt hollow nanoparticles anchored reduced graphene oxide composites for non-enzymatic glucose biosensor

A novel, stable and sensitive non-enzymatic glucose biosensor based on bimetallic hollow Ag/Pt nanoparticles and the reduced graphene oxide (rGO) was obtained. The hybrid of bimetallic hollow Ag/Pt nanoparticles-reduced graphene oxide (HAg/PtNPs-rGO) was prepared by a galvanic replacement reaction and the thermal reduction of graphene oxide. Thermal reduction has been highly effective in producing graphene-like films which can render a stable substrate for hollow Ag/Pt nanoparticles. The morphology and composition of the prepared samples were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectrometry and Fourier transform infrared spectra. Cyclic voltammetry measurements demonstrated that the biosensor decorated by HAg/PtNPs-rGO can directly detect glucose and show a superior electro catalytic activity. The results of amperometric method showed a desirable amperometric response with a sensitivity of 129.32 μA mM⁻¹ cm⁻², a linear range of 0.003–7.72 mM (R² = 0.9943), a fast response time (less than 3 s) and a low detection limit of 1.8 μM (S/N = 3). In addition, the fabricated sensor also had good selectivity, reproducibility and long-term stability. The sensor modified by HAg/PtNPs-rGO could make a promising application in glucose determination.