Department of Analytical Chemistry, Volyn State University, Voli av., 13,
43009, Lutsk, Ukraine, e-mail: email@example.com
Department of Analytical Chemistry, National University of Uzhgorod,
Pidgirna str., 46, 88000, Uzhgorod, Ukraine
Institute of Organic Chemistry, Ukrainian National Academy of Sciences,
Murmantska str., 5, 02600, Kyiv, Ukraine
The state of certain indocyanine derivatives symmetric carbocyanines and asymmetric styryls dyes, in aqueous solutions has been studied. The dyes exist as reactive single-charged forms in a wide acidity range. The spectrophotometric characteristics, protonation and hydrolysis constant has been estimated. The charge distribution in the dyes has been evaluated by quantum-chemical calculations. Protonation mechanism is discussed based on the data UV-, VIS- and NMR-1H - spectroscopy. The results suggest the applicability of the dyes as effective analytical reactants.