Synthesis of Fluorescent Schiff Base Hybrid Nanoparticles for Silver Extraction and their Biological Activity

Abstract In this study, the Schiff‐based Ligand (L1) method was followed for the formation of fluorescent organic nanoparticles (FONPs) as a straightforward and environmentally friendly process. Promoting metal interaction and fluorescence was the aim of ligand L1, which contains functional groups based on imines and sulphur. The resulting FONPs were characterized by UV–vis, FTIR, FE‐SEM, EDX, and P‐XRD techniques, showing efficient nanoparticle synthesis and enhanced optical properties due to electronic delocalisation and π–π stacking. Upon entering into contact with Ag⁺ ions, there were noticeable alterations in the UV–vis absorption spectra, indicating the formation of Ag@FONPs and a high binding affinity. The optimal Ag⁺ concentration for hybrid production was determined to be 2.0 mM; above this concentration, aggregation of the Ag@FONPs occurred, leading to a noticeable drop in absorbance. Furthermore, Ag@FONPs and FONPs have shown promising antibacterial activity against both gram‐positive and gram‐negative bacteria, suggesting potential use in biological and environmental contexts. Because of their adaptability, these fluorescent hybrids are valuable resources for metal ion recovery and antimicrobial platforms. In addition, the distinct optical and antibacterial characteristics of these fluorescent hybrids underscore their possible future uses in environmental remediation, wastewater treatment, and biosensors.