Novel multifunctional Zn Metal−Organic framework fluorescent probe demonstrating unique sensitivity and selectivity for detection of TNP, ANI, TC and LIN in water solution

A novel metal-organic framework (MOF), namely [Zn2(deta)(bpy)]n (1) (H4deta ​= ​4- (3,5-dicarboxyphenoxy) phthalic, bpy ​= ​2, 2′-bipyridine) was successfully prepared and characterized. MOF 1 is a three-dimensional network structure based on binuclear zinc unit, which is constructed by bpy and (deta)4- ions via μ7: η3, η2, η2, η2 coordination mode. It is worth noting that MOF 1 not only has excellent luminescence performance, but also can be regarded as a multifunctional luminescence sensor with high selectivity and excellent sensitivity to detect 2, 4, 6-trinitrophenol (TNP), aniline (ANI), tetracycline (TC) and lincomycin hydrochloride (LIN). Noticeably, when the ANI concentration is 1.96 ​× ​10−5 ​M, the fluorescence of MOF 1 is almost completely quenched, and the quenching efficiency reaches 99.7%. In addition, the fluorescence quenching mechanism of TNP was investigated by electron transfer, energy transfer and energy level orbitals. It is noteworthy that the color of TNP and nitroaromatic compounds (NACs) can be easily distinguished by the naked eye through the difference in fluorescence intensity when detected under 365 ​nm UV light.