A dual-signal electroluminescence aptasensor based on hollow Cu/Co-MOF-luminol and g-C3N4 for simultaneous detection of acetamiprid and malathion

A novel hollow copper-cobalt MOF (Cu/Co-MOF) was synthesized by a template method and characterized by SEM, TEM, XRD, and XPS techniques. The hollow Cu/Co-MOF was used to load the luminol and significantly enhanced the ECL signal of the luminol by catalyzing H2O2 to produce more O2−. Meanwhile, a dual-signal electroluminescence (ECL) aptasensor was established based on the ECL signal of luminol and graphite-like carbon nitride nanosheet (g-C3N4). The dual-signal was observed at −1.5 and 0.6 V, corresponding to the luminescence signals of g-C3N4 and luminol, respectively. This ECL aptasensor for simultaneous detection of acetamiprid and malathion showed good sensitivity with a linear range of 0.1 μM∼0.1 pM, detection limit of 0.015 pM, and 0.018 pM (S/N = 3), respectively. Furthermore, the aptasensor also exhibited reasonable specificity, repeatability, and stability. The prepared ECL aptasensor was applied for the detection of acetamiprid and malathion in apple and tomato samples.