Magnetic Fe3O4/GO nanocomposite-modified graphite-epoxy composite electrode for high-performance glucose sensing

Abstract

An electrochemical sensing platform for glucose sensing was prepared by magnetic loading of Fe₃O₄/GO nanocomposites on graphite-epoxy composite electrode(GECE). The Fe₃O₄/GO nanocomposites were prepared by first preparing GO and then modifying it by co-precipitation of Fe^2 + and Fe³⁺. Since the Fe₃O₄/GO nanocomposites have a magnetic property, they were effectively separated using a magnet and loaded on a graphite-epoxy composite electrode(GECE). The Fe₃O₄/GO/GECE modified electrode was characterized using scanning electron microscopy (SEM), X-ray diffraction analysis(XRD) and cyclic voltammetry (CV). The fabricated biosensor exhibited an excellent electrocatalytic activity. The linear range for glucose is from 0.5 to 6.5 mM with the detection limit of 268.5 µM (S/N = 3) and the sensitivity of 63.5 mA/mM. The effects of interfering substances such as ascorbic acid (AA), uric acid (UA) and dopamine (DA) were also investigated in details. The results confirmed that these interfering substances did not significantly affect the determination of glucose.