Effect of 1-Octyl-3-Methylimidazolium Salicylate as an Active Pharmaceutical Ingredient (API-IL) on the Thermodynamic Behavior of Aqueous Glycine Solutions at T= 298.15 K

Abstract

Background: The thermophysical properties of 1-octyl-3-methylimidazolium salicylate as an active pharmaceutical ingredient based on ionic liquid have been investigated in the presence of aqueous solutions of glycine. Therefore, the scope of this article was to determine these properties by measuring the densities, speeds of sound, viscosities, electrical conductances and refractive indices for ternary (glycine + 1-octyl-3-methylimidazolium salicylate + water) soloutions at T = 298.15 K. Methods: A commercial density and speed of sound measurement apparatus was used to measure the density and speed of sound data. Viscosities, electrical conductivities and refractive indices of the studied solutions were measured using digital viscometer, conductivity meter and refractometer, respectively. Results: Variety of properties such as partial molar volume of transfer , partial molar isentropic compressibility of transfer , viscosity B-coefficients of transfer , ion association constants (KA) and molar refraction RD were determined to investigate the solute-solute and solute-solvent interactions in these systems. Conclusion: The positive values of transfer properties including partial molar volume of transfer ( ), partial molar isentropic compressibility of transfer ( ), and viscosity B-coefficients of transfer (∆traB) indicated that in these systems, the ion-polar and polar-polar interactions are dominant. The calculated hydration number showed that dehydration of glycine occurs in presence of this ionic liquid.

Keywords: 1-Octyl-3-methylimidazolium salicylate, Viscosity B-coefficient, Hydration number, Molar conductivity