As a significant metal ion in the environmental and biological systems, excess or shortage of Fe3+ from the organism can cause a host of diseases. So it is very urgent to explore an explicit, rapid and recoverable method for the detection of Fe3+ ions. Herein, a novel and flexible ligand containing 12 carboxyl groups (BHM-COOH) is used for the structure of a series of luminescent Eu3+/Tb3+-metal-organic frameworks (MOFs). A reliable and convenient luminescent detection platform is constructed by combining polylactic acid (PLA) film with Eu0.24Tb0.76-BHM-COOH. More importantly, the luminescent platform can highly sensitive to sense Fe3+ ions through fluorescence quenching (Stern-volmer constant Ksv = 1.27 × 104 M-1 for Fe(NO3)3), and detection limit can be as low as 4.47 μM. The sensing mechanism is ascribed to the fluorescence quenching caused by the competitive absorption between Eu0.24Tb0.76-BHM-COOH and Fe3+ ion. At the same time, the sensor can be reused many times. These exciting results indicate that Eu0.24Tb0.76-BHM-COOH film can serve as a promising multi-responsive luminescent sensor for environmental pollutant monitoring.

中文翻译：

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通过可生物降解的基于镧系元素金属有机骨架的平台，选择性检测水溶液中的Fe3 +离子。

作为环境和生物系统中的重要金属离子，有机物中Fe3 +的过量或短缺会导致多种疾病。因此，探索一种明确，快速且可回收的Fe3 +离子检测方法非常迫切。在本文中，含有12个羧基的新型柔性配体（BHM-COOH）用于一系列发光Eu3 + / Tb3 +-金属有机骨架（MOF）的结构。通过将聚乳酸（PLA）薄膜与Eu0.24Tb0.76-BHM-COOH结合在一起，构建了一个可靠且方便的发光检测平台。更重要的是，该发光平台可通过荧光猝灭（Fe（NO3）3的斯特恩-沃尔默常数Ksv = 1.27×104 M-1）对检测Fe3 +离子高度敏感，检测限可低至4.47μM。感应机制归因于Eu0.24Tb0.76-BHM-COOH与Fe3 +离子之间竞争性吸收引起的荧光猝灭。同时，传感器可以重复使用多次。这些令人振奋的结果表明，Eu0.24Tb0.76-BHM-COOH膜可以作为一种有前途的多响应发光传感器用于环境污染物监测。