Solubility calculations of branched and linear amino acids using lattice cluster theory
Solubility calculations of branched and linear amino acids using lattice cluster theory
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DOI：
10.1080/00268976.2014.902137
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发表时间：
2014-09
影响因子：
1.7
通讯作者：
M. Fischlschweiger;S. Enders;T. Zeiner
中科院分区：
文献类型：
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作者：
M. Fischlschweiger;S. Enders;T. Zeiner
在这项工作中，活度系数和氨基酸在水中的溶解度的计算使用的晶格集团理论（LCT）结合扩展的化学缔合晶格模型，允许自缔合以及交叉缔合。这使得研究的氨基酸结构对热力学性质的影响的第一次。用该模型对所研究的14种氨基酸（甘氨酸、丙氨酸、γ-氨基丁酸、DL-缬氨酸、DL-苏氨酸、DL-蛋氨酸、L-亮氨酸、L-谷氨酸、L-脯氨酸、羟脯氨酸、组氨酸、L-精氨酸、α-氨基戊酸）的活度系数和溶解度进行了拟合，与实验数据吻合较好。在不同α-氨基酸但不同烃链的情况下，在LCT内可以使用相同的相互作用能参数。所有研究的氨基酸都可以使用相同的参数来描述氨基酸缔合特性。所形成的交叉缔合物含有比由溶液的总摩尔分数表示的更多的氨基酸。此外，交叉缔合物的组成取决于温度，其中氨基酸的量随着温度的升高而增加。
In this work, the activity coefficients and the solubility of amino acids in water were calculated using the lattice cluster theory (LCT) combined with the extended chemical association lattice model allowing self-association as well as cross-association. This permits the study of the influence of the amino acids structure on the thermodynamic properties for the first time. By the used model, the activity coefficient and solubilities of the investigated fourteen amino acids (glycine, alanine, γ-aminobutyric acid, dl-valine, dl-threonine, dl-methionine, l-leucine, l-glutamic acid, l-proline, hydroxyproline, histidine, l-arginine, α-amino valeric acid) could be described in good accordance with experimental data. In the case of different α-amino acids, but different hydrocarbon chains, the same interaction energy parameter can be used within the LCT. All studied amino acids could be modelled using the same parameter for the description of the amino acid association properties. The formed cross-associates contain more amino acids than expressed by the overall mole fraction of the solution. Moreover, the composition of the cross-associates depends on temperature, where the amount of amino acids increases with increasing temperature.