A Fluorescent Probe Based on Cu,Fe-N-C Nanozyme with Oxidase-like Activity for Detection of Phthalate Esters

Abstract

A simple and sensitive fluorescent probe for the determination of phalic acid ester (PAEs) in fermented foods was developed based on the fact that the oxidase-like activity of Cu,Fe-N-C nanozyme can be regulated by PAEs. After PAEs were adsorbed on the surface of Cu,Fe-N-C, the catalytic oxidation of the substrate o-phenylenediamine (OPD) was accelerated, thus increasing the fluorescence intensity of the generated 2,3-diaminophenazine (DAP). The calibration curve for PAEs showed a good linear relationship in the concentration range of 1.25–50 μg/L. The detection limit of the proposed method was 0.76 μg/L. The recoveries of spiked samples ranged from 88.0% to 104.6%, which meet the detection requirements of the national standard GB 5009.271-2016. This method is simple, stable and rapid, and its detection limit is lower than the national limit for PAEs content in foods.

Keywords

• phthalic acid esters; nanozyme; oxidase-like activity; fluorescent probe