Ag@Zn-MOF Composites: A Dual Function Material for Luminescent Detection, Dose Reliant Photodegradation of Ethion Insecticide and Enhanced Bioactivity

Abstract

This work reports the synthesis and detailed characterization of a zinc-based metal–organic framework, [Zn (Cei)]_n (Zn-MOF), constructed using bis(2-carboxyethyl) isocyanurate (H₂Cei) as the ligand, alongside its silver-doped variants (Ag@Zn-MOF-n, where n = 1–3). Comprehensive analyses, including XPS, PXRD, SEM, EDX mapping, Raman spectroscopy, and FTIR, confirmed the successful incorporation of silver ions into the Zn-MOF framework. The photoluminescent sensing capabilities of Ag@Zn-MOF-2 were explored for detecting dimethoate (DMA) and ethion (ETH) insecticides, achieving excellent quenching efficiencies, with detection limits of 2.109 ppm and 2.229 ppm, respectively. The photocatalytic activity of Ag@Zn-MOF-2 was also investigated for the degradation of the insecticides under visible light, where Ag@Zn-MOF-2 demonstrated a significantly higher degradation efficiency (91.37%) for ETH compared to the undoped Zn-MOF (31.89%). Antimicrobial studies revealed that Ag@Zn-MOF-2 exhibited improved activity against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli, with MIC and MBC values of ≤128 mg/L for S. aureus and ≤256 mg/L for E. coli, surpassing the performance of the undoped Zn-MOF. Furthermore, Ag@Zn-MOF-2 showed enhanced antioxidant activity in the DPPH radical scavenging assay compared to the parent Zn-MOF. These results underscore the versatility of Ag@Zn-MOF-2 as a multifunctional material for applications in environmental remediation, pollutant detection, and in the field of biological activity.