Coordinative interaction-enhanced aggregation-induced electrochemiluminescence signal enables ultrasensitive aflatoxin B1 sensing in corn

Aflatoxins B1 (AFB1), as a secondary metabolite of Aspergillus flavus and Aspergillus parasiticus , is the most toxic mycotoxin. It is urgently needed to detect AFB1 pollution in time at ultra-low concentration levels. Aggregation-induced electrochemiluminescence (AIECL) has aroused widespread interest due to the significantly improved ECL response by overcoming aggregation-caused quenching. However, current AIECL probes to satisfy trace AFB1 determination remain a big challenge. Herein, by virtue of hollow UiO-66-NH 2 with multiple active sites, 1,1,2,2-tetra(4-carboxylphenyl)ethylene (TCTPE)-functionalized AIECL probe (TH-UiO-66-NH 2 ) was designed and prepared for constructing an aptamer-based sensor toward AFB1 monitoring. Due to the coordination of TCTPE and Zr 4+ , TCTPE molecules were loaded and largely restricted in hollow UiO-66-NH 2 , leading to a breakthrough in AIECL signal enhancement. Further combined with magnetic separation and accumulated strand displacement, ultrasensitive and selective detection of AFB1 was achieved with an ultra-low detection limit of 1.04 fg/mL, providing new ideas for food safety supervision.