AuAgS/rGO and MnCdO/rGO Nanocomposite-Based Sensors for Electrochemical Detection of Organophosphorus Pesticides

The use of pesticides in agriculture is essential for protecting crops and enhancing yield. However, their widespread application poses significant environmental and health risks. This study focuses on creating novel non-enzymatic electrochemical sen-sors for this purpose. Two nanocomposite-based sensors were developed, one using a bimetallic AuAgS alloy with reduced graphene oxide (AuAgS/rGO) and another using a MnCdO metal oxide with rGO (MnCdO/rGO). These nanomaterials were synthesized and deposited onto fluorine-doped tin oxide (FTO) electrodes. The materials were characterized using techniques such as FESEM, TEM, EDX, XRD, and UV-Vis spec-troscopy. Sensor performance was evaluated using differential pulse voltammetry (DPV) for the detection of diazinon and ethion. Comprehensive characterization con-firmed the successful synthesis and desired morphological properties of the nano-materials. The AuAgS/rGO-based sensor demonstrated exceptional sensitivity, with detection limits of 6 nM/L for diazinon and 50 nM/L for ethion, and wide linear ranges of 12-500 nM/L and 120-490 nM/L, respectively. The MnCdO/rGO sensor was success-fully applied to detect diazinon in a real-world sample of orange wash, confirming its practical utility. This study underscores the potential of these nanocomposite-based sensors as highly sensitive, selective, and practical tools for the precise monitoring of organophosphorus pesticides (OPPs) in environmental and food safety applications.