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Information × Registration Number 0309U007057, 0108U004296 , R & D reports Title Protolytic Equilibria of Indicator Dyes in Nanosized Organized Solutions popup.stage_title Протолітичні рівноваги індикаторних барвників в нанорозмірних організованих середовищах Head Vodolazkaya Natalya Alexandrovna, Registration Date 04-02-2009 Organization Kharkov national university named after V.N. Karazin popup.description2 The objects of research are reaction media of new type, i.e., solutions of four cationic poly(propyleneimine) dendrimers, reversed microemulsions and solutions of cationic calix[4]arene, and traditional ones, such as water-organic mixtures, as well as indicator dyes of various nature. The aim of the study was to reveal regularities of the influence of reaction media, in particular, of organized solutions, microreactors, water-organic mixtures, on the protolytic and related equilibria, on spectral and thermodynamic properties of organic reagents, and to develop approaches for prediction of such influence. Methods of research: potentiometry, spectrophotometry, fluorometry. Aqueous solutions of four cationic poly(propyleneimine) dendrimers have been examined as media for protolytic transformations of indicator dyes. It was shown that these compounds strongly affected acid-base and tautomeric equilibria of dyes, which manifests itself in alteration of indices of apparent ionization constant , the effectshaving much in common with those observed in cationic surfactant micellar solutions. The difference between micelles and dendrimers under study is revealed in kinetics peculiarity of some reactions. Data about influence of ionic strength on the acid-base and spectral characteristics of bromophenol blue in solutions of cationic calix[4]arene are received. Effects were compared ones earlier determined in other systems. values of dye are increased with increasing of ionic strength as in micellar solutions of cationic surfactants. The equilibria of two fluorescein dyes in reversed AOT-stabilized microemulsions were studied. It was revealed that the and values of fluorescein essentially approach each other. For comparison, the equilibria of hydroxyxanthenes in the ternary mixture ethanol - benzene - water (mass ratio 47 : 47 : 6) were studied. The differentiating action of the given ternary mixture is caused by possibilities of selective solvation of dye molecules. The results obtained can be recommended forphysicalchemistry, colloid chemistry, biology and biochemistry, photo- and analytical chemistry, as well as in academic courses of physical and colloid chemistry. Product Description popup.authors popup.nrat_date 2020-04-02 Close