ZIF-67-Derived Hollow Nanozyme with Dual Quenching Mechanisms Coupled with DNA Walker as an Aptasensing Platform for Sensitive Detection of Acetamiprid.

Acetamiprid (ACE) is a widely used neonicotinoid insecticide with high insecticidal efficacy; however, its residues in food and environmental matrices have raised concerns regarding potential risks to human health. In this work, a DNA walker amplification strategy integrating the dual electrochemiluminescence (ECL) quenching pathways of ZIF-67-derived hollow CoFe Prussian blue analogue nanozyme (denoted ZIF-67@CoFe PBA NZ) was proposed for sensitive detection of ACE. Through efficient self-assembly of luminol, Eu3+, and guanosine 5'-monophosphate disodium salt (GMP), the obtained luminol-Eu3+-GMP coordination polymer (Lu-Eu3+-GMP CP) exhibited aggregation-induced electrochemiluminescence (AIECL) characteristics and a stronger and more stable ECL signal. ZIF-67@CoFe PBA NZ exerted a favorable ECL quenching effect and achieved a quenching efficiency of 68.16% through reactive oxygen species (ROS) depletion and ECL resonance energy transfer (ECL-RET). Leveraging the above advantages and DNA walker-mediated signal amplification, the proposed ECL aptasensing platform enabled ACE detection, showing a broad linear range from 1.0 pg/mL to 100 ng/mL and a low detection limit of 0.43 pg/mL. This ECL aptasensing strategy exhibited excellent practical applicability and held great application prospects for food safety analysis.