Synthesis and characterization of PANI/MOF-199/Ag nanocomposite and its potential application as non-enzymatic electrochemical sensing of dopamine

In this research study, a highly selective and sensitive electrochemical sensor was designed by coating the glassy carbon electrode (GCE) with the novel PANI/MOF-199/Ag nanocomposite for the non-enzymatic electrochemical detection of dopamine (DA). PANI/MOF-199/Ag nanocomposite was prepared by the in situ chemical oxidative polymerization of aniline monomer in the presence of MOF-199 followed by the deposition of Ag nanoparticles using an in situ chemical reduction route. Characterization techniques such as Scanning electron microscopy (SEM), X-ray powder diffraction (XRD), Fourier transform infra-red spectroscopy (FTIR), and Raman analysis were used to find out the successful synthesis of the prepared samples. Meanwhile, the electrochemical performance was investigated by chronoamperometry (CA) and cyclic voltammetry (CV) not only at different molar concentrations of DA but also with various compositions of Ag nanoparticles loaded. The PANI/MOF-199/Ag-3% modified electrode exhibited good electro-catalytic activity with high sensitivity of 1.421 µA µM−1 cm−2 and a low detection limit (LOD) of 0.22 µM (S/N = 3) towards DA. Moreover, in the presence of common interfering biological compounds such as glucose (Glu), uric acid (UA), and ascorbic acid (AA), the fabricated electrochemical sensor was found selective to DA detection.