Determination of Hg2+ Based on the Selective Enhancement of Peroxidase Mimetic Activity of Hollow Porous Gold Nanoparticles

Abstract

In this paper, a novel colorimetric biosensor for Hg[Formula: see text] is presented based on Hg[Formula: see text] stimulated peroxidase-like activity of hollow porous gold nanoparticles (HPGNPs). Under mild conditions, HPGNPs show high catalytic activity toward the oxidation of 3, 3[Formula: see text], 5, 5[Formula: see text]-tetramethylbenzidine (TMB) using H2O2 as an oxidant. The peroxidase-like activity of HPGNPs is “switched-on” selectively in the presence of Hg[Formula: see text], which permitted a novel and facile colorimetric sensor for Hg[Formula: see text]. This method exhibits many merits like high selectivity and sensitivity. As low as 18.5[Formula: see text]nM Hg[Formula: see text] could be determined at a linear range from [Formula: see text][Formula: see text]M to [Formula: see text][Formula: see text]M. This method is successfully applied for the determination of total mercury content in tap water and Yellow River which indicates that the method has a great potential for the routine determination of Hg[Formula: see text] in environmental samples.