Electrochemical Sensor with Bimetallic Pt–Ag Nanoparticle as Catalyst for the Measurement of Dissolved Formaldehyde

Abstract

Formaldehyde (FA) in food is harmful to human health, an effective detecting tool is highly desired especially for the on-site test. Herein, an amperometric aqueous FA sensor was fabricated by applying Pt–Ag core-shell nanoparticles as electrocatalyst. The well-characterized core-shell nanostructure exhibits high electro-catalytical activity for the detection of FA molecules in solution due to the synergistic effect of bimetallic Pt–Ag nanostructure. The proposed sensor exhibits high FA sensing performance, with a linear detection range from 1 to 100 μM and a limit of detection (LOD) down to 1.0 μM on the optimized conditions. Interferents coexisting in food samples were efficiently minimized by good selectivity. The Pt–Ag nanostructure-based FA sensor keeps catalytical activity for at least 30 d and shows good batch reproducibility. The proposed sensor was applied for the detection of FA in the food samples and satisfactory results were obtained, showing potential for the fast, simple, disposable, and cost-effective FA detecting method for food safety.