Preparation of a low-toxic biomass-derived carbon dots-based magnetic molecular imprinting electrochemiluminescence sensor for the rapid separation and highly sensitive detection of zearalenone.

Abstract

Zearalenone (ZEN), a common mycotoxin, has significant threat to human and animal health, so its rapid and sensitive detection in foods is quite important. In this work, a magnetic molecular imprinting electrochemiluminescence (ECL) sensor was proposed for its detection, which was constructed by loading carbon dots (CDs) with Fe3O4 magnetic nanoparticles (MNPs) and then coating them with a molecular imprinted polymer (MIP). The CDs were prepared using waste coffee grounds, enabling low-cost and large-scale production. After polyethyleneimine modification, the CDs could generate strong ECL signal in the presence of tri-n-propylamine. Through siloxane cross-linking, the CDs were anchored onto the MNPs surface, and the MIP was simultaneously formed. The resulting molecularly imprinted nanoparticle exhibited low cytotoxicity under tested conditions and was able to rapidly enrich and separate ZEN. The obtained sensor demonstrated high stability, sensitivity, reproducibility, selectivity, and anti-interference capability. Under optimized conditions, the ECL intensity was linear to the logarithm of ZEN concentration in the range of 1.0 × 10-3-3.2 × 102 ng mL. When applied to detect ZEN in grain samples (including corn, wheat flour, and rice), the spiked recoveries ranged from 90.1 % to 109 %, with relative standard deviation below 7.2 %. This work provides a novel approach for the low-cost and rapid detection of mycotoxins.