An Eu-doped Zr-metal-organic framework for simultaneous detection and removal of antibiotic tetracycline

Due to the widespread use of tetracycline (TC), there is an increasing demand for rapid detection as well as effective removal of residual tetracycline for environment and food safety. Herein, we report an Eu/Zr-MOF material that combines the high adsorption performance of water-stable Zr-MOF and the unique emission characteristics of Eu3+, which enables both sensing and adsorption functions for TC. Eu/Zr-MOF can be achieved facilely by doping Eu3+ into Zr-MOF via the traditional hydrothermal method. In aqueous medium, the Eu3+ preferentially coordinate with TC molecules, which in turn acts as an antenna for UV–Vis absorbance to enhance the characteristic fluorescence of Eu3+. In such way, TC can be specifically detected in a wide dynamic range (0.001–0.5 µg/mL) with a low detection limit (0.00092 µg/mL). Moreover, by taking advantage of the unsaturated character of ZrO centers, the Eu/Zr-MOF has a TC loading capacity as high as 289 mg g-1. As a consequence, based on the Eu/Zr-MOF, rapid detection and efficient removal of TC from food and environment was realized at once. The principle of design proposed in this work may find more applications to synthesize new platforms for simultaneous sensing and removal of specific pollutants.