Designing Zinc- and Cadmium-Based Luminescent Metal-Organic Frameworks for Antibiotic Detection: Structure-Function Relationships, Sensing Mechanisms, and Future Perspectives.

The widespread presence of antibiotic residues in environmental and food systems poses serious risks to ecological safety and accelerates antimicrobial resistance, creating an urgent need for rapid, selective, and sensitive detection methods. This review highlights the recent advances in Zn(II)- and Cd(II)-based metal-organic frameworks (MOFs) as luminescent sensing platforms for antibiotic monitoring. Owing to their diverse structures, tunable porosity, and versatile coordination chemistry, these MOFs enable efficient detection of various antibiotic classes, including tetracyclines, sulfonamides, fluoroquinolones, nitrofurans, nitroimidazoles, amphenicols, β-lactams, and cephalosporins. Key design strategies, such as ligand engineering, pore-environment modulation, metal-node selection, and hybrid framework construction, are discussed in relation to sensing performance. Particular emphasis is placed on structure-property relationships governing selectivity, sensitivity, and detection limits. Major fluorescence sensing mechanisms, including photoinduced electron transfer (PET), Förster resonance energy transfer (FRET), inner filter effect (IFE), aggregation-induced emission (AIE), and intramolecular charge transfer (ICT), are critically compared. The review further addresses challenges related to framework stability, selectivity, and real-sample applicability, while outlining future directions involving multifunctional sensors, portable detection devices, and artificial intelligence (AI)-assisted MOF design. Overall, this review provides practical guidelines for the rational development of next-generation Zn- and Cd-based MOF sensors for antibiotic detection.