Improvement of Amperometric Biosensor Performance for H2O2 Detection based on Bimetallic PtM (M = Ru, Au, and Ir) Nanoparticles

Abstract

Novel bimetallic nanoparticles have been synthesized via rapid microwave irradiation, leading to an improved sensitivity and a highly anti-interference property for amperometric biosensor in H2O2 detection. The material characterizations were performed by TEM, XRD, and EDX, which show the bimetallic formation of Pt-based catalysts and well-dispersed nanoparticles of 2–5 nm. The sensitivities for the detection of H2O2 of PtRu, PtAu, and PtIr as the biosensor working electrode catalysts are 539.01 (R2=0.99), 415.46 (R2=0.99), and 404.52 (R2=0.97) μA mM−1 cm-2, respectively, nearly twice higher than the pure Pt catalyst (221.77 μA mM−1 cm−2, R2=0.98), at a low applied potential of +0.25 V versus Ag/AgCl. Furthermore, Pt-Ru and Pt-Ir show a highly sensitive response and a promising anti-interference capability to ascorbic acid, a major interferent, by reducing the interferent current as low as 7-8% significantly lower than that of Pt (30% change). The enhancement of both sensitivity and selectivity in the bimetallic catalysts can be found practical applications in biosensing.