Unveiling the effect of crystallinity and particle size of biogenic Ag/ZnO nanocomposites on the electrochemical sensing performance of carbaryl detection in agricultural products

In this study, bio-Ag/ZnO NCs were synthesized via a microwave-assisted biogenic electrochemical method using mangosteen (Garcinia mangostana) peel extract as a biogenic reducing agent for the reduction of Zn2+ and Ag+ ions to form hybrid nanoparticles. The as-synthesized NC samples at three different microwave irradiation temperatures (Z(70), Z(80), Z(90)) exhibited a remarkable difference in size and crystallinity that directly impacted their electrocatalytic behaviors as well as electrochemical sensing performance. The obtained results indicate that the Z(90) sample showed the highest electrochemical performance among the investigated samples, which is attributed to the improved particle size distribution and crystal microstructure that enhanced charge transfer and the electroactive surface area. Under the optimal conditions for carbaryl pesticide detection, the proposed nanosensor exhibited a high electrochemical sensitivity of up to 0.303 mu A mu M-1 cm(-2) with a detection limit of LOD similar to 0.27 mu M for carbaryl pesticide detection in a linear range of 0.25-100 mu M. Overall, the present work suggests that bio-Ag/ZnO NCs are a potential candidate for the development of a high-performance electrochemical-based non-enzymatic nanosensor with rapid monitoring, cost-effectiveness, and eco-friendly to detect carbaryl pesticide residues in agricultural products.

Automated summary

Bio-Ag/ZnO NCs were synthesized using mangosteen peel extract as a reducing agent. The samples synthesized at different microwave temperatures showed significant differences in size and crystallinity, affecting their electrocatalytic behavior and sensing performance. The Z(90) sample exhibited the highest electrochemical performance due to improved particle size distribution and crystal microstructure. The proposed nanosensor showed high electrochemical sensitivity (0.303 μA μM-1 cm(-2)) and a low detection limit (LOD≈0.27 μM) for carbaryl pesticide detection. Overall, bio-Ag/ZnO NCs are promising for the development of a high-performance electrochemical-based nanosensor for rapid and eco-friendly detection of carbaryl pesticide residues in agricultural products.