Influence of the composition of aqueous-alcohol solvents on thermodynamic characteristics of dl-¦Á-alanyl-dl-norleucine dissolution at 298.15 K
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- 作者：Valeriy I. Smirnov ; Valentin G. Badelin
- 关键词：Peptide ; Water ; Alcohols ; Enthalpy of solution ; Enthalpy of transfer ; Mixed solvent
- 刊名：Thermochimica Acta
- 出版年：2012
- 出版时间：20 September, 2012
- 年：2012
- 卷：544
- 期：Complete
- 页码：43-46
- 全文大小：344 K
文摘
Dissolution enthalpies (¦¤solHm) of dl-¦Á-alanyl-dl-norleucine in binary mixtures containing water + (EtOH, 1-PrOH and 2-PrOH at 0-0.4 mole fraction) at 298.15 K and atmospheric pressure have been determined as a function of the composition using an isothermic calorimeter. The results obtained have been used to calculate standard enthalpies of a solution (¦¤solH¡ã) and transfer (¦¤trH) of dl-¦Á-alanyl-dl-norleucine from water into the mixtures as well as enthalpy coefficients of pairwise interaction (hxy) of the solute with alcohols in aqueous media. The ¦¤trH¡ã values are positive for all mixtures over the whole composition range. The influence of the co-solvent structure and of the content of mixtures and of a side-chain of peptide on the change of ¦¤trH¡ã (hxy) is discussed.