Co-based metal-organic framework nanopinnas composite doped with Ag nanoparticles: A sensitive electrochemical sensing platform for simultaneous determination of dopamine and acetaminophen

Abstract Hybridizing nanostructured metal nanoparticles with metal-organic framework is greatly promising for the enhancement of electrochemical performance of sensor. In the present study, an Ag nanoparticles-ZIF-67 nanopinnas composite material (Ag-ZIF-67p) has been fabricated by ultrasonication and reduction of a metal precursor (AgNO3) within ZIF-67 nanopinnas template. The desired Ag-ZIF-67p was characterized by transmission electron microscopy with energy dispersive X-ray analysis and elemental mapping, powder X-ray diffraction, X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy. The Ag-ZIF-67p was modified on the GCE and demonstrated enhanced electrocatalytic activity toward dopamine (DA) and acetaminophen (AP) owing to synergetic properties of large porosity and surface area of ZIF-67 and the high conductivity and excellent catalytic activity of Ag nanoparticles. The results revealed broader linear range toward analysis of DA and AP with low detection limit of 0.2 and 0.05 μM (S/N = 3) for AP and DA, respectively. In addition, this Ag-ZIF-67p modified electrode also showed excellent selectivity for the detection of two compounds and prospective results in real tablets and dopamine hydrochloride injection samples.