The Mixing Effect of Glycylglycine with KCl, KBr, and Na2SO4 from Volumetric and Viscometric Investigations at 298.15 K

The mixing effect of a simple peptide such as glycylglycine, in the presence of aqueous electrolytes, has been studied by examining their volumetric and viscometric behavior. The increase in the apparent molar properties of both glycylglycine and electrolytes is attributed to the interactions present among cation, anion, the head groups of the peptide, and the peptide bond. Simple equations are developed to account for such interactions with a view to correlate apparent molar properties of glycylglycine and electrolyte in their aqueous mixtures. Transfer properties of both glycylglycine and electrolyte are investigated in order to understand the changes in the property of one component by the addition of another. These interactions are also supported by viscosity data, for which a simple model is developed to correlate the variation in viscosities with composition of a component.