Highly sensitive photoelectrochemical sensor based rGO/CuI-modified glassy carbon electrode for monitoring chloramphenicol

Abstract

Carbon-nanomaterials-based photoelectrochemical sensors have received attention and become promising methods in analytical techniques due to their unique benefits, such as easy fabrication, high sensitivity, and selectivity. Herein, the rGO/CuI-modified glassy carbon electrode (rGO/CuI-GCE) has been fabricated to enhance the sensitivity detection of chloramphenicol (CAP). The rGO/CuI was synthesized using the co-precipitation method, while the rGO/CuI-GCE was fabricated using a dropping technique on the GCE surface. The properties of rGO/CuI were studied by x-ray diffraction (XRD), fourier transform infrared (FTIR), raman spectroscopy, UV–Vis spectroscopy, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM). Furthermore, using a three-standard electrode, the photoelectrochemistry of rGO/CuI-GCE was studied by observing the photocurrent response to time (i vs t). Under optimal conditions, the rGO/CuI-GCE sensor presented significant CAP detection performance in the 0–40 uM with a detection LOD of 8.6 nM (S/N = 3). The sensor also has good stability and selectivity. In addition, the developed sensor was successfully applied to detect CAP in fresh milk and urine with a good % recovery value. The developed photoelectrochemical sensor based on rGO/CuI-modified GCE offers a promising approach for enhancing the sensitivity detection of CAP and others.