Three fluorescent asymmetric bis-urea receptors (L1-L3) have been synthesised. The binding properties of L1-L3 towards different anions (fluoride, acetate, hydrogencarbonate, dihydrogen phosphate, and hydrogen pyrophosphate HPpi(3-)) have been studied by means of (1)H-NMR, UV-Vis and fluorescence spectroscopy, single crystal X-ray diffraction, and theoretical calculations. In particular, a rema...

Three fluorescent asymmetric bis-urea receptors (L1-L3) have been synthesised. The binding properties of L1-L3 towards different anions (fluoride, acetate, hydrogencarbonate, dihydrogen phosphate, and hydrogen pyrophosphate HPpi3-) have been studied by means of 1H-NMR, UVVis and fluorescence spectroscopies, single crystal X-ray diffraction, and theoretical calculations. In particular, a remarka...

An azo-based dye (I) was designed for the detection of cyanide by utilizing a new indirect method. In the presence of Cu(II), compound I could give rise to visible red-to-yellow color change. The resultant yellow solution could change to red immediately upon the addition of trace cyanide, with the detection limit of 0.15 ppm, but no changes were observed in the presence of other anions, includi...

Boronic acids play an important role in the design and synthesis of chemosensors for carbohydrates due to their ability to reversibly bind with diol-containing compounds. Along this line, the availability of boronic acids that change fluorescence upon sugar binding is critical to a successful sensor design effort. Here, two boronic acids that show strong fluorescent intensity changes upon sugar...

A new rhodamine B-based dual-function chromo- and fluorogenic probe for Cu(2+) and ClO(-) has been designed, synthesized, and characterized. The probe comprises a spectroscopic unit of rhodamine B and a Cu(2+)-specific chelating unit of pyridinecarboxamide as well as a ClO(-)-specific reactive moiety of diacylhydrazine, and is a highly selective and extremely sensitive fluorescent and colorimet...

A novel fluorescent Probe 1, based on phenanthro-imidazole has been developed as an efficient chemosensor for the trace detection of copper ions (Cu2+). Probe 1 demonstrated sensitive fluorescence quenching upon binding with Cu2+ through 1:1 stoichiometric chelation. The detection limit for Cu2+ ions was projected through linear quenching fitting to be as low as 2.77 × 10-8 M (or 1.77 ppb). The...

A series of novel thiourea based receptors (1-12) with different signaling units and spacers have been synthesized for the detection of cyanide ion. Among these receptors, 4,4'-bis-[3-(4-cyanophenyl)thiourea]diphenyl sulfide 6 and 4,4'-bis-[3-(3-cyanophenyl)thiourea]diphenyl sulfide 9 exhibited selective detection of cyanide by the naked-eye as well as by UV-Vis spectroscopy. Furthermore, the c...