A Novel Rotaxane@MOF as Multiresponsive Fluorescence Sensor for Detecting Fe<sup>3+</sup>, Cr<sub>2</sub>O<sub>7</sub><sup>2–</sup>, and Antibiotics
Li-Xia He, Xiao Xiao, Yao-Mei Fu, Ning-Hao Wang, Jing Sun, Xinlong Wang, Xingqi Han, Zhong‐Min Su, Xue-Song Wu
Abstract
The first example rotaxane@MOF (named as CUST-761 ) has been designed and constructed via combining CB[6]-based rotaxane ([PR44] 2+ ·2[NO 3 ] − ), 4,4′-biphenyldicarboxylate sodium salts (Na 2 BPDC), and transition metal cadmium ion under solvothermal conditions. X-ray single crystal diffraction revealed CUST-761 exhibits a two-dimensional (2D) layered structure where rotaxanes are well embedded in the crystal lattices formed by BPDCs and cadmium ions. Thermogravimetric analysis (TGA) and Powder X-ray diffraction (PXRD) showed that CUST-761 possesses excellent stability. The utility of CUST-761 as fluorescence sensors has also been discussed. The results indicated that CUST-761 can be used as a multiresponsive fluorescence sensor for detecting Fe 3+ and Cr 2 O 7 2– with good sensitivity, high selectivity, and recoverability, even in the presence of other interfering ions. Besides, CUST-761 also can selectively detect nitrofurantoin. The mechanism of CUST-761 as a multiresponsive fluorescence sensor for detecting Fe 3+, Cr 2 O 7 2–, and the antibiotic nitrofurantoin has been clarified by experiments and theoretical calculations. This work provides insights into the design and synthesis of fluorescence sensing crystal-state materials.