Electrochemiluminescent\nResonance Energy Transfer\nSensor for Malathion Based on Zn Luminophore/Prussian Blue Nanostructure\nComposites

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