Gadolinium stannate nanoparticles decorated 2D-graphene oxide nanolayer composite for effective electrochemical detection of chloramphenicol in food samples

Abstract

A highly and simply sensitive electrochemical sensor has been developed for the determination of chloramphenicol (CAP) in food samples based on gadolinium stannate (Gd₂Sn₂O₇ denote as GdSnO) reinforced graphene oxide (GdSnO/GO) composite modified classy carbon electrode (GCE) (GdSnO/GO/GCE). GdSnO/GO composite was synthesized using an ultrasonication technique and confirmed by analytical and spectroscopic methods, including PXRD, FT-IR, FE-SEM, EDX mapping, XPS, and HR-TEM. Further, the electrocatalytic activity of GdSnO/GO/GCE was investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Under the optimized experimental conditions, the fabricated sensor exhibited a low limit of detection (LOD) of 98 nm, a linear range of 0.02 − 522.43 µM, and sensitivity is 0.41 μA μM⁻¹ cm⁻². Additionally, the constructed sensor demonstrated impressive repeatability, reproducibility, and superior selectivity in the presence of other co-interference including metal ions, biological molecules, and nitro compounds, enabling the electrochemical detection of CAP. Additionally, the modified electrode was applied in the determination of CAP in the food samples such as milk and honey. The recoveries were between 99.69–102.86 % and 97.85–99.34 % with relative standard deviations (RSD) ranging from 1.03 % – 1.33 %, indicating that GdSnO/GO/GCE was suitable for the determination of CAP in food samples.