Reduced Graphene Oxide/Pt Nanoparticles/Zn-MOF-74 Nanomaterial for a Glucose Biosensor Construction

Abstract

In this study, a new glucose biosensor was fabricated by immobilizing glucose oxidase (GOx) on platinum nanoparticles (Pt NPs) decorated reduced graphene oxide (rGO)/Zn-MOF-74 hybrid nanomaterial. Herein, the biosensor fused the advantages of rGO with those of porous Zn-MOF and conductive Pt NPs. This has not only enlarged the surface area and porosity for the efficient GOx immobilization and faster mass transport, but also provided favorable electrochemical features such as high current density, remarkable electron mobility through metal nanoparticles, and improved electron transfer between the components. The GOx-rGO/Pt NPs@Zn-MOF-74 coated electrode displayed a linear measurement range for glucose from 0.006 to 6 mM, with a detection limit of 1.8 mu M (S/N: 3) and sensitivity of 64.51 mu A mM(-1) cm(-2). The amperometric response of the enzyme biosensor demonstrated the typical behavior of Michaelis-Menten kinetics. The obtained satisfying sensitivity and measurement range enabled fast and accurate glucose measurement in cherry juice using the fabricated biosensor. The water-stable Zn-MOF-74 demonstrated higher enzyme loading capacity and can be potent supporting material for biosensor construction.