CuX/Sulfur-Doped C₃N₄ Nanocomposite-Modified Glassy Carbon Electrode for Electrochemical Detection of Dopamine

The present study reported the synthesis of three CuX/S-doped g-C 3 N 4 nanocomposites (CuX= CuO/CuS/Cu 2 O) via an efficient and simple approach. The various prepared nanocomposites were characterized with different characterization techniques and demonstrated the synthesis of pure nanocomposites. Among three CuX/S-doped g-C 3 N 4 nanocomposites, CuS/S-doped g-C 3 N 4 exhibits a remarkable electrochemical performance for detecting dopamine (DA). Herein, various electrochemical parameters, such as the volume of the electrocatalyst used and the solution’s pH, were optimized to achieve efficient detection. Under favorable conditions, CuS/S-doped g-C 3 N 4 demonstrated an effective electrochemical response for DA detection using linear sweep voltammetry (LSV) and cyclic voltammetry (CV) methods. The proposed sensor afforded a linear plot between the anodic peak current and concentration of DA in the range of 0–200 μM with the low limit of detection (0.1227 μM or 122.7 nM) between the concentration of DA and anodic peak current. In addition, the constructed sensor for DA detection displayed satisfactory stability and reproducibility. The real sample, i.e., human serum, was employed to assess the ability to perform real-time analysis of the sensing platform. The developed sensor displayed a favorable recovery rate, illustrating its practical functionality.