A Benzothiadiazole-Based Eu 3+ Metal-Organic Framework as the Turn-On Luminescent Sensor toward Al 3+ and Ga 3+ with Potential Bioimaging Application.

The design and preparation of novel multifunctional lanthanide metal-organic frameworks (Ln-MOFs) have been arisen widespread attention. In particular, Ln-MOFs have shown great luminescence potential in chemical sensing. Herein, a new benzothiadiazole-based Eu-MOF {[(CH 3 ) 2 NH 2 ][Eu(BTDB) 2 ]·2H 2 O} n ( JXUST-11 ) was obtained based on 4,4'-(benzo[ c ][1,2,5]thiadiazole-4,7-diyl)dibenzoic acid (H 2 BTDB), which exhibits a chain-based three-dimensional framework. Moreover, JXUST-11 is considered as a photoluminescent sensor to identify Al 3+ and Ga 3+ ions by fluorescence enhancement with the detection limits of 2.9 and 10.2 ppm, severally. Importantly, Al 3+ and Ga 3+ can be discerned with the naked eye by color change under a natural lamp. In addition, a portable MOF film based on JXUST-11 was developed for Al 3+ and Ga 3+ detection. This is the first Ln-MOF that can be employed as a naked-eye fluorescent probe to identify Ga 3+ . Interestingly, JXUST-11 is also capable of detecting Al 3+ and Ga 3+ in living cells.