Gu_2025_Biosens.Bioelectron_279_117398

To prevent organophosphorus pesticide (OPs) residues from threatening ecological environment safety and human health, the development of rapid and accurate monitoring methods is crucial. Herein, a newly quantum dot-functionalized metal-organic framework composite (IRMOF-3/CdTe) was synthesized, which achieved super strong cathodic electrochemiluminescence (ECL) emission in aqueous media. Among them, as a co-reaction accelerator, IRMOF-3 could efficiently enrich K(2)S(2)O(8) and catalyze its generation of sulfate radical (SO(4)(-)), while protecting metastable intermediates from environmental quenching, synergistically improving the ECL signal intensity. Moreover, by optimizing the synthesis ratio of IRMOF-3/CdTe and combining ECL intensity and electrochemical impedance spectroscopy (EIS) analysis, it was revealed for the first time that IRMOF-3 exerts a dual-edged effect on the ECL performance of CdTe. Based on the efficient ECL performance of IRMOF-3/CdTe and the inhibitory effect of OPs on acetylcholinesterase (AChE) activity, a highly sensitive ECL enzyme biosensor was constructed to detect profenofos (Pff). The fabricated biosensor exhibited a wide detection range (134 fM-1.34 mM) and a low detection limit (44.7 fM), and was successfully applied to the detection of Pff residues in actual samples (vegetables, milk and Yangtze River water). This study provided a new idea for the design of efficient ECL enzyme biosensors, which was of great significance for ensuring ecological and food safety.