Utilizing a water-stable terbium (III) metal-organic framework for luminescent sensing of nitroimidazole antibiotics

A new 3D terbium (III)-based metal–organic framework, [Tb(TDC)(µ2-CH3COO)(H2O)] (Tb-MOF, H2TDC = 2,5-thiophenedicar-boxylic acid), was obtained with Tb3+ ions as metal source and TDC ligands as the auxiliary ligand through self-assemble mode. The Tb-MOF features a 3D network constructed by bridging a 2D wave-like network connected by TDC ligands with monodentate coordination mode, which results in the formation of a 3D net framework. The luminescent properties and sensing antibiotics experiments were extensively investigated for the Tb-MOF. Remarkably, the Tb-MOF exhibits a substantial quantum yield (QY) at 55.0 % and an average photoluminescence lifetime of 534 µs. Furthermore, the Tb-MOF shows selective luminescence quenching for nitroimidazole antibiotics, including metronidazole (MDZ), dimetridazole (DTZ), and ornidazole (ODZ), with a particularly strong response for MDZ (Ksv = 5.49 × 104 M−1, LOD value is 7.9 × 10−5 M). Finally, the Tb-MOF enables a simple and convenient test paper that allows luminescent color changes to be observed with the naked eye for detecting MDZ.