Synthesis and photophysical properties of indolenine styrylcyanine dye and its carboxyl-labeled derivative

Abstract

The indolenine styrylcyanine dye and its carboxyl-labeled derivative were synthesized using condensation of the corresponding indolenines with 4-(dimethylamino) benzaldehyde in the presence of an alkaline catalyst. The spectral-luminescent properties of studied dyes in organic solvents, the aqueous solution (pH 7.9), and the presence of different biomacromolecules were investigated. The functionalization of the dye structure by the carboxylic group led to a bathochromic shift of fluorescence emission spectra while having no impact on dye specificity. It is established that studied styrylcyanines exhibited no or low preference towards biomacromolecules and no accumulation at a specific site within cells.