Guseva G.B.

ZINC(II) BIS(DIPYRROMETENATES) AS NEW FLUORESCENT CHEMOSENSORS OF N- AND O-CONTAINING ANALYTES

The results of spectral studies of the fluorescence of binuclear zinc(II) bis(dipyrrinate)s with 3,3′-, 2,3′- and 2,2′-bis(dipyrrine)s of the composition [Zn2L2] in binary mixtures of cyclohexane and N- and O -containing solvent Х (acetone, DMF, DMSO, TEA) are presented. Spectrophotometric studies have shown that additive in cyclohexane of analyte upto χХ<0.2 leads to red shift (to ~10 nm) of emission band maximum and to a sharp de-crease in fluorescence quantum yield (φ) of [Zn2L2] luminophores. The observed effect is due to the additional coordination processes of the electron-donor molecules X, leading to the formation of solvates [Zn2L2Xn]. The efficiency of fluorescence quenching of [Zn2L2], formed by 3,3′, 2,3′- or 2,2′-bis(dipyrrine)s, is different. Zinc(II) 3,3′-bis(dipyrrometenat) demon-strates the highest sensitivity to fluorescence at the presence of X, as compared with the 2,3′- and 2,2′-analogues.

2016, Т. 59, № 6, Стр. 22-27

NEW COLORIMETRIC AND FLUORESCENT CHEMOSENSORS BASED ON DIPYRROMETHENE DYES

Synthetic bis(dipyrromethene)s (H2L) is very promising compounds to create sensory systems due to a combination of spectral-luminescent and chelating properties which sensitive to structural and solvation effects. Reactions of H2L·2HBr salts with amines are accompanied by changes in the color of the solution and a clear show a transformations of H4L2+ salt spec-trum in the H2L spectrum with a large (about 40 nm) difference between maxima of their in-tense bands which allows the use of 3,3'-bis(dipyrromethene) salts as colorimetric chemosen-sors of amines with sensitivity of detection upto 1·10–8 mol/l. The basis for the development of applied directions of using 3,3-bis(dipyrromethene)s as a fluorescent chemosensors of Zn2+, Cd2+ and Hg2+ ions is the bright coloristic effects, accompanying reactions of H2L with Zn(II), Cd(II) and Hg(II) salts, and significant differences in quantitative characteristics of the spec-tra of the complexes [M2L2] and ligands.

2016, Т. 59, № 6, Стр. 16-21
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