Interactions between several l-α-amino acids and potassium chloride in aqueous solutions at 298.15 K

Abstract

The enthalpies of solution of l-α-aminobutyric acid, l-α-valine, l-α-leucine, l-α-isoleucine, and l-α-cysteine have been measured in aqueous potassium chloride solutions at 298.15 K. From the obtained experimental results the standard dissolution enthalpies of amino acids in aqueous KCl solutions have been determined. These data were used to calculate the heterogeneous enthalpic pair interaction coefficients based on McMillan–Mayer’s theory. These values were interpreted in the terms of the hydrophobic or hydrophilic effects of the side chains of amino acids on their interactions with dissociated potassium chloride in water.