Adsorption and detection of ofloxacin with Eu-doped Al-organic framework

The growing concerns regarding the ecological and human health risks posed by ofloxacin (OFC) contamination have intensified the demand for advanced multifunctional materials to address antibiotic pollution in wastewater. In this study, a europium(III) functionalized metal-organic framework (Eu@MOF-303) was developed as a dual-functional platform for adsorption and fluorescence-based detection of OFC. Through post-synthetic modification, Eu³⁺ ions were anchored onto MOF-303′s porous structure, serving as chelating centers for target capture and luminescent signal transduction. The Eu@MOF-303 demonstrated exceptional OFC adsorption capacity of 1688.66 mg·g^-1, attributed to its high surface area (916.32 m²·g^-1), favorable surface charge (68.01 mV), and abundant Eu³⁺-derived active sites. Mechanistic studies revealed that synergistic interactions—including hydrogen bonding, π-π stacking, and coordination bonding—governed the adsorption process. Furthermore, Eu@MOF-303 exhibited unique fluorescence properties with characteristic red emission at 615 nm, enabling selective OFC detection via a static quenching mechanism. The Eu@MOF-303 achieved a low detection limit of 3.27 µM across a wide linear range (0–200 µM), while maintaining remarkable selectivity towards quinolone antibiotics. Notably, the OFC-saturated adsorbent displayed enhanced antibacterial activity, suggesting secondary utility in microbial control. This study presents a pioneering strategy for designing intelligent materials that integrate pollutant removal, environmental monitoring, and antibacterial ability as a versatile solution for sustainable wastewater remediation.