The enthalpies of solution of L-serine were measured in water and aqueous solutions of isopropanol, 1,2-propanediol and propanetriol at 298.15 K with an RD-496III microcalorimeter. Enthalpies of transfer (ΔH_trs) of L-serine from water to aqueous solutions were calculated as well. From the experimental result it was found that both the values of enthalpies of solution and enthalpies of transfer of L-serines were positive, indicating that it was endothermic. They were increased with the increasing of concentration of alcohols. Such evidence illustrated that in the process of solution the endothermic of the partial dehydration of solute and molecules of mixed solution was predominant. In addition it was also found that the enthalpies of transfer of L-serine from water to aqueous isopropanol solution is larger than that from water to aqueous 1,2-propanediol and propanetriol solution. This could be illuminated by the reinforcement of hydrophilic-hydrophobic interaction and by the weakening of hydrophilic-hydrophilic interaction.

Key words: enthalpy of solution, L-serine, alcohol, interaction of structure