Specific Electrochemical Sensing of 4-Aminophenol Using a Graphene Oxide/Calcium Phosphate Nanocomposites Material for Pharmaceutical and Environmental Applications

Abstract

A graphene oxide-hydroxyapatite (GO/HA) nanocomposite was synthesized by a simple co-precipitation method and applied for the electrochemical determination of 4 -aminophenol (4- AP). Structural, morphological, and functional group characterizations were carried out using Xray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, and Raman spectroscopy. The electrochemical behavior of 4-AP at the GO/HA-modified glassy carbon electrode was investigated by cyclic voltammetry and differential pulse voltammetry. The modified electrode exhibited enhanced electron-transfer kinetics toward 4-AP, achieving a low detection limit of 0.14 nM and a wide linear concentration range of 0.1–340 μM with a correlation coefficient of R2 = 0.9974. The high sensitivity is attributed to the synergistic effect of graphene oxide and porous hydroxyapatite within the nanocomposite. The proposed GO/HA-based sensing platform is rapid, simple, and sensitive, demonstrating potential applicability for the determination of 4-AP in pharmaceutical formulations and industrial wastewater samples.