An OFF–ON–OFF type of pH fluorescent sensor: Benzo[c,d]indole-based dimethine cyanine dye-synthesis, spectral properties and density functional theory studies

Meso-Substituent-Directed Aggregation Behavior and Water Solubility: Direct Functionalization of Methine Chain in Thiazole Orange and Biological Applications in Aqueous Buffer

“…Figure D indicates that the molecules of 1 are stacked nearly parallel to each other via π–π interactions with face-to-face distances of 3.68 Å . Thus, it is prone to aggregate in a parallel way (plane-to-plane stacking) to form a sandwich-type arrangement (H-aggregates). − In the contrary, benzothiazole ring planes are parallel to each other in the crystal packing of 2a and 2b (Figure A,B), while the quinoline ring planes are parallel to each other in 2f (Figure C). Among these, intermolecular π–π interaction is significantly reduced, and the corresponding aggregation is retarded.…”

Polymethine Dye as Sensors of NH3 and CO

“…The restructuring of the dye molecule during the interaction with other molecules leads to a change in its properties that are essential for using the dye as a core element of sensor devices [4][5][6][7][8][9][10][11].…”

A Class of Multiresponsive Colorimetric and Fluorescent pH Probes via Three Different Reaction Mechanisms of Salen Complexes: A Selective and Accurate pH Measurement

“…Nonetheless, designing and building the system of off–on–off fluorescent pH probes is complicated and unexpected. Until now, thess kinds of probes are much scarcer, , because a fluorescent pH probe usually would tend to show only one “off–on” fluorescence response under different pH values even though it has multiple pH-sensitive recognition moieties. ,,,, …”