AIEgen-based porous organic polymer-Ag nanoparticles hybrids with coreaction accelerator amplification and covalent rigidification-enhanced electrochemiluminescence for aflatoxin M1 detection

Developing new high-performance electrochemiluminescence (ECL) emitters is a continuous hotspot. Herein, a novel AgNP-decorated porous organic polymer (AgNPs@ETTBC-BPyDAN-POP, BPyDAN = 2,2′-([2,2′-bipyridine]-5,5′-diyl)diacetonitrile) nanocomposite with coreaction accelerator amplification and covalent rigidification-enhanced ECL was prepared. AgNPs@ETTBC-BPyDAN-POP nanocomposite exhibited excellent ECL performance, not only because abundant AIE-active 4′,4″′,4″″′,4″″″′-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1′-biphenyl]-4-carbaldehyde)) (ETTBC) luminogens were covalently assembled and rigidified into ETTBC-BPyDAN-POP network, which diminished radiationless transition, but also because AgNPs functioned as coreaction accelerators that expedited the generation of coreactant radicals, which in-situ react with adjacent ETTBC + intermediates, thereby producing more ETTBC ⁎ excited states for significantly enhancing the ECL emission. Considering the eminent ECL performance, AgNPs@ETTBC-BPyDAN-POP was employed as an ECL indicator to fabricate a supersensitive biosensor for detecting aflatoxin M1, showing a wide response range (5 fg/mL − 500 ng/mL) with a detection limit of 0.57 fg/mL. Overall, this study offered a promising dual-enhancement strategy to boost AIEgens' ECL emission, thereby providing significant inspiration to develop high-efficiency AIEgen-based ECL materials for fabricating hypersensitive ECL biosensors.