Bodipy Based Fluorescent Materials in Cellulose Matrices: Synthesis, Spectral Properties and Vapochromic Fluorescent Recognition of Alcohols and Acetone.

This paper highlights advances made using the 4-bora-3a,4a-diaza-s-indacene (BODIPY) as a fluorophore in design and application of fluorescent sensors for microenvironment polarity. Sections of the paper cover broad analysis of a range of fluorescent indicators immobilized in ethyl- and methyl cellulose matrices. The present study demonstrates that BODIPY-based fluorescent materials could be successfully utilized for ratiometric detection of ethanol and acetone in gas phase. The achieved limit of detection value equals 0.02 mg/ml for acetone and 0.08 mg/ml for ethanol, whereas obtained sensoric materials are reusable without regeneration required.

Liquid crystalline poly(propylene imine) dendrimer-based iron oxide nanoparticles.

Poly(propylene imine) dendromesogens (generations from 1 to 4) have been utilized for the synthesis and stabilization of ferrimagnetic Fe2O3 nanoparticles. Reduction of Fe(iii) with further oxidation of Fe(ii) results in the formation of highly soluble nanocomposites of iron oxides in a dendrimer, which are stable under a wide range of temperatures. The magnetic iron oxide nanoparticles were investigated by MALDI-ToF MS spectrometry and elemental analysis. To establish the type of mesophase, X-ray measurements were performed at different temperatures. The calculations of X-ray results demonstrate a hexagonal columnar packing of the molecules in the mesophase. Observation of the samples by TEM gives information about the size of the compounds as well as direct evidence of the implementation of Fe2O3 nanoparticles into dendrimers. Physical parameters of the magnetic nanoparticles (magnetic moment, effective magnetic anisotropy) have been determined from analyses of the EPR data.

«Ðžn-off¼ fluorescent sensors for aromatic analytes based on zinc(II) bis(dipyrromethenate)s.

This paper presents the results of spectral-luminescence research of binuclear zinc(II) helicates with tetra-, octa-, and decamethylsubstituted 3,3'-bis(dipyrromethene)s ([Zn2L2]) in binary mixtures of cyclohexane with aromatic hydrocarbons (benzene, toluene, and m-xylene). Structure effects of zinc(II) helicates, and aromaticity criteria of analytes (HOMA, NICS, δ) on the fluorescence quenching efficiency of [Zn2L2] in the presence of aromatic compounds was considered. It was found that decamethylsubstituted 3,3'-bis(dipyrromethenate)s compared to tetra-, and octamethylsubstituted-analogs shows the highest fluorescence sensitivity to the presence of aromatic compounds. High specificity of spectral-luminescence characteristics changing in the presence of particular aromatic analytes provides the possibility of using [Zn2L2] helicates as new fluorescent sensors of aromatic compounds trace amount (120ppb to 56ppm) in organic media.

Influence of Solvation and Structural Contributions on Fluorescence of Dipyrrine Dyes.

The results of quantum-chemical and spectral researches of zinc((II)) complexes with alkylated dipyrrine and 3,3'-, 2,3'- and 2,2'-bis(dipyrrine)s in non-polar and polar solvents and their binary mixtures are presented. It was investigated the efficiency of the fluorescence quenching of fluorophores depending on of the solvation and structural contributions. Found that 3,3'-bis(dipyrrinato)zinc((II)) demonstrates the highest sensitivity of the fluorescence to the presence of the electron-donor component compared with the studied complexes. The obtained results allow to offer dipyrrine and bis(dipyrrine) zinc((II)) complexes as new, highly sensitive and selective fluorescent sensors of the N- and O-containing toxicants. Graphical Abstract Influence of solvation and structural contributions on fluorescence of dipyrrine dyes.