A fluorescent probe for detection of Hg(2+) ions constructed by tetramethyl cucurbit[6]uril and 1,2-bis(4-pyridyl)ethene

In this paper, tetramethyl cucurbit[6]uril (TMeQ[6]) and 1,2-bis(4-pyridyl)ethene (G) were used to construct a supramolecular fluorescent probe G@TMeQ[6]. The host–guest interaction between TMeQ[6] and G was investigated using (1)H NMR spectroscopy, single-crystal X-ray diffraction and various experimental techniques. The results show that TMeQ[6] and G form an inclusion complex with a host–guest ratio of 1:1 and the equilibrium association constant (K(a)) was 2.494 × 10(4) M(−1). The G@TMeQ[6] fluorescent probe can sensitively recognize Hg(2+) ions by fluorescence enhancement. The linear range is 0.33 × 10(−5)–1.65 × 10(−5) mol·L(−1), R(2) = 0.9926, and the limit of detection is 4.12 × 10(−8) mol·L(−1). The fluorescent probe can be used to detect the concentration of Hg(2+) ions in aqueous solution, and provides a theoretical basis for the development of new fluorescent probes for detecting heavy metal ions.