A new Eu(III)-based Metal-Organic Frameworks as a Ultrasensitive Fluorescence sensors for Tetracycline and Fe3+ in aqueous solution

In this study, a new three-dimensional metal organic framework (MOF) named [Eu 2 (L) 3 (H 2 O) 2 ] n ( 1 ), act as the ultrasensitive fluorescence sensors for tetracycline and Fe 3+ in aqueous solution, have been successfully synthesized by using the 2-(1H-pyrazol-4-yl) terephthalic acid (H 2 L) and Eu(NO 3 ) 3 ·6H 2 O as the building units via the solvothermal synthesis procedure. Structure analysis reveal that 1 show a 3D molecular structure based on a binuclear secondary building units (SBUs). And also, the physical and chemical stability show that 1 show the good stability under the strong acid and alkali aqueous solution. The fluorescence properties explorations of 1 show that 1 exhibits the attractive fluorescence performances in detecting tetracycline (TC) and Fe 3+ ions with the LODs of 3.77361 × 10 −5 M for Fe 3+ and 1.21958 × 10 −6 M for TC, which is comparable and even exceed the publications. The sensing mechanism have also been seriously explored. And importantly, the recycling experiments reveal that 1 exhibited good recyclability in fluorescence recognition after multiple experiments, which may provide us with a potential optical material for fast and efficient detection of Fe 3+ ions and TC.