Biogenic Silver Nanoparticles from Citrus reticulata Peels for Ultrasensitive Electrochemical Sensing of 4-Aminobenzenesulfonamide

Increasing utilization of sulfonamide derivatives as antibacterial agents has created serious challenges in terms of environmental pollution and antimicrobial resistance. In this respect, there is a compelling need for a highly sensitive and selective analytical tool for detecting such antibiotics in trace concentrations. This work represents a green strategy for developing an electrochemical biosensor for the determination of 4-aminobenzenesulfonamide based on bio-functionalized silver nanoparticles (Ag NPs) prepared from peel extract of Citrus reticulata fruit. The phytochemicals present in the peel extracts played a dual role of reduction and stabilization during the synthesis of Ag NPs. Synthesized NPs were well characterized through scanning electron microscopy (SEM), X-ray diffraction (XRD), Ultraviolet spectroscopy (UV–Vis), and Fourier infrared spectroscopy (FTIR) techniques. The Ag NPs showed considerable improvement in electrocatalysis in comparison to the bare glassy carbon electrode. The fabricated sensor gave an excellent linear calibration curve with a high value of R2 (=0.999), along with a low limit of detection (LOD = 0.65 µM) and limit of quantification (LOQ = 2.1 µM).