Studies of interaction between ninhydrin and Gly-Leu dipeptide: Influence of cationic surfactants (m-s-m type Gemini)

Herein, we have reported the studies of interaction between ninhydrin and glycylleucine (Gly-Leu) dipeptide in cationic Gemini surfactants (m-s-m; m = 16; s = 4, 5, 6) by using spectrophotometric technique. The rate constant values, k(psi) were determined at different temperatures and pH. The effect of concentration of reactants and surfactants was also carried out on the title reaction. It was also observed that the reaction was accelerated and catalyzed by 16-s-16 Gemini surfactants even at low critical micelle concentration (cmc) value of surfactants. The variation of Gemini surfactants on the reaction of ninhydrin with glycylleucine has been analyzed with the help pseudo-phase model of surfactants proposed by Menger and Portnoy and developed by Bunton. The binding constants for reactants (ninhydrin and Gly-Leu) have been computed using a computer based program. (C) 2018 Elsevier B.V. All rights reserved.