Electrochemiluminescent Resonance Energy Transfer Sensor for Malathion Based on Zn Luminophore/Prussian Blue Nanostructure Composites

The intensive application of organophosphorus pesticides (OPs) and their acute toxicity have raised significant threats to human health. Herein, an electrochemiluminescence (ECL) nanomaterial was synthesized by successive modification of the Zn–N structure and Prussian blue (PB) nanoparticles on cerium(III) tetrakis(4-carboxyphenyl)porphine (CeTCPP). Because of the combination of CeTCPP (luminophore) and the Zn–N structure (coreaction accelerator) in one nanostructure, Zn-CeTCPP exhibited a high ECL response based on the self-enhancement strategy. The ECL signal was remarkably quenched in turn due to the resonance energy transfer (RET) from Zn-CeTCPP to PB. However, PB was disassembled in the presence of acetylcholinesterase and acetylthiocholine since the produced acetic acid and thiocholine destroyed PB and reduced PB to Prussian white, respectively. Therefore, the recovered ECL signal was employed to sensitively detect malathion with a wide linear range of 1.0 × 10–13–1.0 × 10–7 g/mL and a low limit of detection of 13 fg/mL, endowing the present ECL-RET sensor with excellent prospects for practical application based on the self-enhancement and acceptor disassembly strategies.