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

Abstract

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 Φ) and the standard partial molar volumes (V Φ 0) at (298.15 and 308.15) K have been calculated. The values of standard partial molar volumes of transfer (Δtr V Φ 0) are also obtained and are negative for glycine, l-alanine, and l-phenylalanine while positive for l-arginine. The Δtr V Φ 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.

Apparent molar volume, conductivity, and fluorescence studies of ternary systems of dipeptides + ionic liquids ([Cnmim]Br, n = 10, 14) + water at different temperatures

“…The relatively freer NH 3 + and COO − end Table 1 Standard partial molar volumes (V 2,φ 0 ) and experimental slopes S V for three glycyl dipeptides in aqueous [C n mim]Br (n=10, 14) solutions at different temperatures groups in glycylglycine will cause the maximum volume contraction followed by glycylvaline and least by glycylleucine in which the polar end groups are highly shielded by the bulky group -CHCH 3 CH 3 for electrostriction. Similar results were found for dipeptides in aqueous sodium carboxylate solutions [18][19][20][21] and amino acid in aqueous ionic liquid [5,22], methanoic acid [23], sodium fluoride [24], cetyltrimethylammonium bromide solutions [25], and so on. Furthermore, Fig.…”

“…However, for more complex systems including biomolecules such as proteins, nucleic acids, saccharides, and so on, experimental measurements on their physicochemical properties are still scarce because of the complex configurational and conformational aspects of macromolecule structure in aqueous solution. There have been some investigations on the interaction of ILs with some small biomolecules, such as amino acids [5][6][7][8] and monosaccharides [9][10][11]. However, to the best of our knowledge, few reports [12] are available in the literature on the interactions of some small peptides with ILs in aqueous solutions at different temperatures.…”

Exploring Diverse Interactions of Some Surface-Active Ionic Liquids with Amino Acids Prevalent in Aqueous Environments by Physicochemical Contrivance

“…Additionally, they can also be considered as green and designer solvent/electrolytes because of their uniqueness [3,[10][11][12][13][14]. In recent years, ILs are also used to frame the thermophysical properties of aqueous solution containing amino acid(s) (AA) and ILs which provides important information about the intermolecular interactions in solution phase [15][16][17][18][19][20]. Amino acids are used as model compounds as they are building block of proteins.…”

Solvation behavior of glycine and diglycine in aqueous 1-butyl-3-methylimidazolium chloride ionic liquid solutions at different temperatures

“…Molecular structure and intermolecular forces play an important role in determining the thermodynamic properties of liquids which in turn depend upon the manner in which components are associated with each other. Various reports are available in literature [4][5][6][7][8][9] on the density and speed of sound for the binary mixtures of ILs with some organic solvents, however the studies on the thermodynamic and thermo physical behavior of binary mixtures of amino acids in aqueous ionic liquids are very limited [10][11][12][13][14]. The thermodynamic data of binary mixtures of ILs with amino acids are required to understand the molecular interactions existing in mixtures.…”