Recognition of Different Metal Cations by a trans-4-[4-(Dimethylamino)styryl]-1-methylpyridinium Iodide@Tetramethylcucurbit[6]uril Probe

Graphical The probe responds to Cs + cations in alkali metal systems, Ba 2+ and Sr 2+ cations in alkaline earth metal systems; Eu 3+ , Tm 3+ , and Yb 3+ cations in lanthanide systems, and Cr 3+ , Fe 3+ , and Hg 2+ cations in systems containing transition and other metal cations, by obvious fluorescence quenching. Based on the study of a known host–guest inclusion complex comprising cucurbit[6]uril (Q[6]) and a hemicyanine dye, trans -4-[4-(dimethylamino)styryl]-1-pyridinium iodide ( t -DSMI), a water-soluble symmetric tetramethylcucurbit[6]uril (TMeQ[6]), was selected to construct a t -DSMI-based probe to test the response to various metal cations in neutral water. The experimental results revealed that the probe responded to Cs + cations in alkali metal systems, Ba 2+ and Sr 2+ cations in alkaline earth metal systems, Eu 3+ , Tm 3+ and Yb 3+ cations in lanthanide systems, and Cr 3+ , Fe 3+ and Hg 2+ cations in systems containing transition and other metal cations, via obvious fluorescence quenching.