Heterogeneous interaction between zwitterions of some l-α-amino acids and ethanol molecule in water at 298.15 K

Dissolution enthalpies of l-α-aminobutyric acid, l-α-isoleucine, l-α-serine, l-α-threonine and l-α-cysteine in water and aqueous ethanol solutions have been measured by calorimetry at a temperature of 298.15 K. The obtained results were used to calculate the enthalpic heterogeneous pair interaction coefficients between zwitterions of amino acids and a molecule of ethanol in water. These values were interpreted in the terms of the hydrophobic or hydrophilic effects of the side chains of amino acids on their interactions with a polar molecule of ethanol in water.