Optical devices for the detection of cyanide in water based on ethyl(hydroxyethyl)cellulose functionalized with perichromic dyes.

Films of three polymers, based on ethyl(hydroxyethyl)cellulose functionalized with protonated perichromic dyes, were used for anion sensing. The polymer functionalized with protonated Brooker's merocyanine acts as a chromogenic/fluorogenic system for the selective detection of cyanide in water. An increase of >28 times was verified for the fluorescence lifetime of the sensing units in the polymer in comparison with protonated Brooker's merocyanine in water.

Nitro-substituted 4-[(phenylmethylene)imino]phenolates: solvatochromism and their use as solvatochromic switches and as probes for the investigation of preferential solvation in solvent mixtures.

Four 4-[[(4-nitrophenyl)methylene]imino]phenols (2a-d) were synthesized. After deprotonation in solution, they formed the solvatochromic phenolates 3a-d, which revealed a reversal in solvatochromism. Their UV-vis spectroscopic behavior was explained on the basis of the interaction of the dyes with the medium through combined effects, such as nonspecific solute-solvent interactions and hydrogen bonding between the solvents and the nitro and phenolate groups.

A simple and efficient anionic chromogenic chemosensor based on 2,4-dinitrodiphenylamine in dimethyl sulfoxide and in dimethyl sulfoxide-water mixtures.

Solutions of 2,4-dinitrodiphenylamine (1) in dimethylsulfoxide (DMSO) are colorless but upon deprotonation they become red. Addition of various anionic species (HSO(4)(-), H(2)PO(4)(-), NO(3)(-), CN(-), CH(3)COO(-), F(-), Cl(-), Br(-), and I(-)) to solutions of 1 revealed that only CN(-), F(-), CH(3)COO(-), and H(2)PO(4)(-) led to the appearance of the red color in solution. The presence of increasing amounts of water in solutions containing 1 made it progressively selective toward CN(-) and the system with the addition of 4.