Nanoporous N-Rich Zn Metal–Organic Framework and Its Mixed-Matrix Membranes for Turn-On Detection of Norfloxacin in River Water and Fingerprint Visualization

Excessive use of antibiotics causes serious environmental pollution, and luminescence sensing can easily and quickly detect trace antibiotic residues in water systems. In this paper, a nanoporous 2D robust Zn-MOF (LCU-126) and its mixed-matrix membranes (MMMs) were well fabricated with N-rich functional sites for detecting iota norfloxacin (NOR) by a significant luminescence enhancement effect. The efficient luminescence sensing performance incorporates high selectivity and sensitivity, good anti-interference and recycling stability, fast response time, and a very low detection limit (LOD) of 0.1007 and 0.1706 ppb in real river water solutions for LCU-126 and its MMMs, respectively. Moreover, the luminescent test strips and latent fingerprint visualization further expanded its practical application in more convenient, fast, and real-time naked eye monitoring of NOR. Multiple experiments and DFT calculations reveal a possible photoinduced electron transfer (PET) luminescence enhancement sensing mechanism. These results evidence that LCU-126 is an advanced luminescent sensing material for detecting and monitoring NOR antibiotic residues in complex real water media.