Construction of High-Performance Amperometric Acetaminophen Sensors Using Zn/ZnO-Decorated Reduced Graphene Oxide Surfaces

Abstract

Sensitive and selective monitoring of acetaminophen (APAP), which is small but an important molecule used to relieve pain and inflammation, is of great importance in pharmacy. This study reports the development of zinc (Zn)/zinc oxide (ZnO)/reduced graphene oxide (rGO)-based electrochemical APAP sensors with a high sensitivity in a wide linear range. The Zn/ZnO/rGO nanohybrids were synthesized using a facile chemical precipitation method. The Zn and ZnO nanoparticles were anchored on the surface of rGO simultaneously during the synthesis process. The XRD and TEM results indicated the presence of Zn and ZnO nanoparticles on the rGO surface, which was also confirmed by the XPS and TGA analyses. The electrochemical performance of the sensors was investigated using cyclic voltammetry (CV) and chronoamperometry (CA) methods. The electrochemical sensing results showed that the sensors had a high sensitivity of 166.5 ± 6 µA.mM-1.cm-2 in the linear range between 0.05 to 2 mM, which is considerably wide compared to the literature. Overall, the Zn/ZnO/rGO nanohybrids displayed a great promise to be employed in the development of electrochemical APAP sensors by having a high sensitivity, wide working window, excellent fabrication reproducibility, good storage stability, selectivity, and real sample analysis results.