A novel electrochemical active electrode based on isopolyacid ion IMo6O245- (IMo6), Pt and graphene oxide (GO) had been fabricated, which was used as a biosensor in double signal amplification platform for simultaneous detection of ascorbic acid (AA), dopamine (DA) and uric acid (UA). Cyclic voltammetry, amperometry and differential pulse voltammetry indicated that a glass carbon electrode modified with Pt/IMo6/GO (Pt/IMo6/GO-GCE) presented higher electrochemical activity toward the oxidation of AA, DA and UA and faster response than those of a bare GCE, GO-GCE, Pt/GO-GCE and IMo6/GO-GCE. As an electrochemical sensor, the Pt/IMo6/GO-GCE showed a wide linear range of 50–4000 μM, 4–750 μM, and 75–300 μM with the limits of detection (S/N = 3) as 6.4 μM, 0.22 μM and 0.72 μM, corresponding to AA, DA and UA, respectively. In addition, the Pt/IMo6/GO-GCE provided a new option in the simultaneous determination of AA, DA and UA in human blood serum with reliable recovery.

Published in: "Journal of the Electrochemical Society".