Europium-based metal-organic framework containing characteristic metal chains: A novel turn-on fluorescence sensor for simultaneous high-performance detection and removal of tetracycline

The misuse of tetracycline (TC) will cause adverse effects on environment and has become a serious problem threatening human health. In this work, a novel bifunctional europium-based metal organic framework (1) containing characteristic metal chains was successfully synthesized via a facile one-pot hydrothermal method for the first time and used in simultaneous detection and removal of TC. Detailed characterizations including scanning electron microscope, energy dispersive X-ray spectroscope, Fourier-transform infrared, X-ray diffraction and X-ray single crystal diffraction were conducted to confirm the successful synthesis of 1. Subsequently, the prepared 1 showed significant fluorescence enhancement at 615 nm with a wide sensitive range (0.05–60 μM) and low detection limit (3 nM) for detection of TC under pH 9. The excellent adsorption behaviours (387.14 mg g−1) of 1 toward TC were demonstrated by kinetic and equilibrium experiments. Possible mechanisms of recognition and adsorption including host-guest capability of Eu nodes, hydrogen bonding, π-π interactions and electrostatic attraction were further explored. In addition, the practical feasibilities of 1 for TC sensing were further investigated in real samples with satisfactory recoveries (94.89 %−112.86 %, RSD ≤ 6.03 %). This work provides a facile strategy for design of MOF-based bifunctional turn-on fluorescence sensor for efficient TC monitoring.