Gold-copper-doped lanthanide luminescent metal-organic backbone induced self-enhanced molecularly imprinted ECL sensors for ultra-sensitive detection of chlorpyrifos

Abstract

Herein, a self-enhanced molecularly imprinted polymer luminescence (MIP-ECL) sensing platform based on gold-copper doped Tb-MOFs (Au@Cu:Tb-MOFs) was constructed for ultra-sensitive detection of chlorpyrifos (CPF). In this work, Au@Cu:Tb-MOFs as co-reaction promoters greatly improve the ECL emission signal, while Au@Cu:Tb-MOFs were used as cathode emitters. And chlorpyrifos and 4,7-bis(thiophene-2-yl)benzo [c][1,2,5] thiadiazole were electropolymerized on electrode surface to form MIP, where this films with thiophene derivatives could greatly improve ECL signal. Notably, the introduction of MIP as recognition elements enabled specific identification of target analytes, in which molecular docking technique validated target analyte and functional monomers are tightly bound through Pi-alkyl interaction. As the concentration of CPF increases, the ECL signal gradually decreases, showing a good linear relationship in the range of 0.1-10⁶ pg/mL with a low detection limit (LOD) of 0.029 pg/mL. Moreover, actual sample testing experiment of this method displayed a special correlation in organophosphorus detection and development potential in actual sample analysis.

Keywords: Chlorpyrifos; Electrochemiluminescence; Lanthanide luminescent metal–organic frameworks; Molecular docking technique; Organophosphorus detection.