Fabrication of Ag/CeO₂/NiO nanocomposite for antibacterial, antibiofilm, and cypermethrin remediation applications

The development of nanocomposites (NCs) for multifunctional applications, including antimicrobial activity and environmental remediation to assess microbial contamination and pesticide levels, has been described. In the present work, a ternary Ag/CeO 2 /NiO nanocompsite (NC) was rapidly synthesized via a green chemical route. Coconut water is used as both a reducing and a stabilizing agent for CeO 2 NPs. Plasmon resonance absorbance peaks of AgNPs, CeO₂NPs, and NiONPs were observed at ~411 nm, ~362 nm, and ~300 nm, respectively, by UV–Vis spectroscopy and confirmed the characteristic metal–oxygen vibration by FTIR spectroscopy. SEM–EDX revealed a nanoscale heterogeneous morphology and confirmed the presence of Ag, Ce, Ni, and O. The NC displayed significant antibacterial and antibiofilm activity (~86% biofilm inhibition) against Staphylococcus aureus . The environmental sensing potential of the NC was further investigated using cypermethrin as a model pesticide analyte. A concentration-dependent change in absorbance was observed after reacting with cypermethrin across the studied concentration range (8–40 mg), demonstrating its potential for pesticide monitoring. Overall, our results suggested the NC as a potential nanoplatform towards combining antimicrobial, antibiofilm, and cypermethrin-monitoring applications.