Solid-state electrochemiluminescence sensor based on zeolitic imidazolate framework-67 electrospinning nanofibers for chlorpyrifos detection

A novel solid-state electrochemiluminescence (ECL) sensor for chlorpyrifos (CPF) detection was constructed based on zeolitic imidazolate framework-67 electrospinning nanofibers (ZIF-67 NFs). Silver nanoparticles (Ag NPs), ZIF-67 NFs, tris(2,2′-bipyridyl) ruthenium(II) [Ru(bpy) 3 2+ ], and Nafion were successively deposited on the surface of the electrode. Ag NPs played a role in promoting electron transfer, and ZIF-67 NFs played a role in fixing Ru(bpy) 3 2+ and promoting electron transfer due to its large specific surface area and porosity. Nafion formed a film on the outermost layer of the electrode to further improve the stability of the system. Therefore, the modified electrode showed stable and obvious ECL signal in PBS solution containing 10 μL 0.01 M TprA (pH 8.0). CPF quenched the ECL signal of the system, and the quenching value was linear with the logarithm of CPF concentration in the range 1.0 × 10 −13 to 1.0 × 10 −6  M. The detection limit was 3.3 × 10 −14  M (S/N = 3). In this study, ZIF-67 NFs were used as an ECL promoter for the first time, broadening the application range of ZIF-67 NFs. Graphical abstract