Ion-imprinted electrochemical sensor based on copper nanoparticles-polyaniline matrix for nitrate detection

Abstract

This study reports a new chemical sensor based on ion-imprinted polymer matrix using copper nanoparticles-polyaniline nanocomposite (IIP-Cu-NPs/PANI). This sensor was prepared by electropolymerization using aniline as a functional monomer and nitrate as template onto the copper nanoparticles-modified glassy carbon (GC) electrode surface. Both ion-imprinted (IIP) and nonimprinted (NIP) electrochemical sensor surfaces were evaluated using UV-Visible spectrometry and scanning electron microscopy (SEM). The electrochemical analysis was made via cyclic voltammetry (CV), linear sweep voltammetry (LSV), and impedance spectroscopy (IS). Throughout this study various analytical parameters, such as scan rate, pH value, concentration of monomer and template, and electropolymerization cycles, were optimized. Under the optimum conditions, the peaks current of nitrate was linear to its concentration in the range of 1M-0.1M with a detection limit of 31M and 5M by EIS and LSV. The developed imprinted nitrate sensor was successfully applied for nitrate determination in different real water samples with acceptable recovery rates.