AuPt Alloy Nanostructures with Tunable Composition and Enzyme-like Activities for Colorimetric Detection of Bisulfide

Abstract

Tuning the enzyme-like activity and studying the interaction between biologically relevant species and nano-enzymes may facilitate the applications of nanostructures in mimicking natural enzymes. In this work, AuPt alloy nanoparticles (NPs) with varying compositions were prepared through a facile method by co-reduction of Au3+ and Pt2+ in aqueous solutions. The composition could be tuned easily by adjusting the molar ratios of added Pt2+ to Au3+. It was found that both peroxidase-like and oxidase-like activity of AuPt alloy NPs were highly dependent on the alloy compositions, which thus suggesting an effective way to tailor their catalytic properties. By investigating the inhibitory effects of HS− on the enzyme-like activity of AuPt alloy NPs and natural enzyme, we have developed a method for colorimetric detection of HS− and evaluation of the inhibiting effects of inhibitors on natural and artificial enzymes. In addition, the responsive ability of this method was influenced largely by the composition: AuPt alloy NPs show much lower limit of detection for HS− than Pt NPs while Pt NPs show wider linear range than AuPt alloy NPs. This study suggests the facile way not only for synthesis of alloy nanostructures, but also for tuning their catalytic activities and for use in bioanalysis.

Mimicking horseradish peroxidase and oxidase using ruthenium nanomaterials

“…[30][31][32] Among these, much work is centered on the noble metal-based nanozymes, particularly gold, platinum, palladium, and iridium, because of their well-developed synthesis techniques, easy modication of surface, excellent catalytic activity, good bio-compatibility and so on. [33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48] For instance, gold nanoparticles with different surface modications or their combined nanomaterials have been reported to demonstrate different enzyme-like activities. Platinum nanostructures are outstanding catalysts and have been found to possess diverse functional activities similar to peroxidase, catalase, superoxide dismutase, polyphenol oxidase, ascorbate oxidase and ferroxidase.…”

Colorimetric sensing of chlorpyrifos through negative feedback inhibition of the catalytic activity of silver phosphate oxygenase nanozymes

“…24 Researchers also found both peroxidase and oxidase-like activities for AuPt alloy NPs using TMB as a chromogenic material. 25 Rope-like Co-Fe layered hydroxide nanosheets based on hierarchical structures were studied for intrinsic oxidasecatalytic activity. 26 Citrate-capped silver nanoparticles exhibit oxidase activity to detect the concentration of mercury ions (II).…”

Functional Enzyme Mimics for Oxidative Halogenation Reactions that Combat Biofilm Formation

“…In addition, we start to understand the mechanisms by which metalloenzymes catalyze such a wide range of complex chemical reactions. Enzymes bind their substrates with exceptional specificity, and catalysis is achieved typically with the aid of two or more functional groups. This allows for substrate selectivity, reaction selectivity, and stereoselectivity.…”