Effect of 1-Ethyl-3-methylimidazolium Bromide Ionic Liquid on the Volumetric Behavior of Some Aqueous L-Amino Acids Solutions

Densities of aqueous solutions of glycine, L-alanine, L-arginine, and L-phenylalanine containing 1-ethyl-3-methylimidazolium bromide, [EMIm]Br, have been determined at T = (298.15 and 308.15) K. From the experimental density data, the apparent molar volumes (V-Phi) and the standard partial molar volumes (V-Phi(0)) at (298.15 and 308.15) K have been calculated. The values of standard partial molar volumes of transfer (Delta V-tr(Phi)0) are also obtained and are negative for glycine, L-alanine, and L-phenylalanine while positive for L-arginine. The Delta V-tr(Phi)0 values all increased with the increase of the temperature and also the [EMIm]Br content. The obtained volumetric parameters will be helpful to understand mixing effects and other complex biological processes between head and side chain groups of amino acids and ionic liquid [EMIm]Br in aqueous solution.