ZnO nanoparticles coated with EDTA and Ag nanoparticles (ZnO@EDTA-Ag NPs) for enhanced electrochemical detection of Cu2+ ions in food and environmental samples
Chama Mabrouk, Jassem Wannassi, Pedro Salazar, Soledad Carinelli, Andrew J. Gross, Hamza Kahri, Nicole Jaffrézic‐Renault, Houcine Barhoumi
Abstract
• This study presents a novel ZnO@EDTA-Ag sensor for precise Cu 2+ ion detection. • Ag nanoparticles enhance electroactivity, sensitivity, and conductivity of the sensor. • The sensor offers a low LOD of 7 nM, high selectivity, stability, and reproducibility. • Sensor was tested in real samples, proving useful for food and environment safety. Copper ions (Cu 2+ ) play a crucial role in biological functions but can be toxic at elevated concentrations. Monitoring Cu 2+ levels in food and water is vital for public health and environmental safety. In this study, we developed a novel electrochemical sensor for Cu 2+ detection using a composite of EDTA-coated ZnO nanoparticles and silver nanoparticles (ZnO@EDTA-Ag). Characterization techniques, including Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD), confirmed the structural and morphological enhancements, which contributed to improved electron transfer and efficient Cu 2+ detection. The cost-effective ZnO@EDTA-Ag material demonstrated superior catalytic properties, making it highly suitable for rapid and sensitive Cu 2+ sensing. The sensor exhibited excellent electrocatalytic properties for Cu 2+ detection, with a wide linear range (0.007 μM to 10 μM) and a low detection limit of 7 nM. It showed high sensitivity, stability and reproducibility, along with promising recovery rates in complex samples such as avocado juice, apple juice, lemon juice, and pond water. This work highlights the potential of the sensor for reliable and cost-effective Cu 2+ detection in real-world applications.