Synthesis and characterization of a sensitive and selective Fe^(3+) fluorescent sensor based on novel sulfonated calix[4]arene-based host-guest complex

A novel fluorescent sensor was prepared from sulfonated calix[4]arene(SC4A)by the host-guest com-plexation method using the fluorescent dye rhodamine B(RB)as a structure-directing agent.The crystal structure of the host-guest complex(RB@(SC4A)_(3))was confirmed by X-ray diffraction studies while its performance and sensing mechanism for metal ion pollutants were characterized using fluorescence and nuclear magnetic resonance spectroscopies.The results showed that RB@(SC4A)_(3) had a triangular branch structure resulting from host-guest mediation of the interactions between the three SC4A host molecules and the three terminal groups of the guest molecule RB.The host-guest complex exhibited sensitive and selective sensing towards Fe^(3+)ions via a fluorescence quenching mechanism.The results indicated that RB@(SC4A)_(3) could be a promising sensitive and selective fluorescent sensor for metal ion pollutants mon-itoring.It also provided new insights into the synthesis of calixarene-based host-guest complex.

Double-cavity nor-seco-cucurbit[10]uril-based supramolecular assembly for selective detection and removal of trinitrophenol

The effective removal and selective detection of explosive and toxic pollutant trinitrophenol (TNP) is an attractive but challenging field.Herein,a double-cavity nor-seco-cucurbit[10]uril (ns-Q[10])-based supramolecular assembly 8-HQ@ns-Q[10]was fabricated and its structure was characterized by X-ray single crystal diffraction.In this assembly,the stoichiometric ratio of ns-Q[10]and 8-hydroxyquinoline (8-HQ) is 1:2,which is also attributed to the special double-cavity structure of ns-Q[10].The luminescence sensing experiments showed that 8-HQ@ns-Q[10]can be used as a good fluorescence-enhanced sensing material (enhanced 27-fold) for the rapid detection of explosives and the aqueous contaminant TNP,with a limit of detection (LOD) of 2.07×10^(-5)mol/L,without interference from other phenolic compounds.Furthermore,TNP can be efficiently removed in the presence of assembly 8-HQ@ns-Q[10],and the removal efficiency is more than 89%.Therefore,the supramolecular assembly 8-HQ@ns-Q[10],as a fluorescenceenhanced luminescence sensor and adsorption material,has rich research value and potential application prospect when applied to the detection and removal of TNP in aqueous environment.