In the framework of the two-dimensional non-ideal solution model, surface layer equations of state, adsorption isotherms and functions of the distribution of protein molecules in respect to different molar area were derived. The thermodynamic analysis was based on Butler's equation for the chemical potentials of the components and a first-order model for the non-ideality of surface layer enthalpy and entropy. For concentrated solutions, aggregation of protein molecules in the surface layer was assumed. The resulting equations satisfactorily describe the measured adsorption and surface pressure isotherms of proteins at liquid/fluid interfaces in terms of a set of constant parameters. The model reflects the well-known differences between proteins and ordinary surfactants: a sharp increase in the surface pressure with concentration beyond a certain protein adsorption; an almost constant surface pressure at higher concentrations and a significant increase in the adsorption layer thickness with increasing adsorption for flexible proteins.

中文翻译：

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在二维溶液模型的框架中描述蛋白质在水/流体界面的吸附行为。

在二维非理想溶液模型的框架内，推导了表面层的状态方程，吸附等温线以及蛋白质分子在不同摩尔面积上的分布函数。热力学分析是基于Butler方程的组分化学势和一阶模型的表层焓和熵的非理想性。对于浓缩溶液，假定蛋白质分子在表面层中聚集。所得方程式根据一组恒定参数令人满意地描述了在液体/流体界面处测得的蛋白质吸附和表面压力等温线。该模型反映了蛋白质与普通表面活性剂之间众所周知的差异：浓度超过某种蛋白质吸附浓度时，表面压力急剧增加；在较高浓度下几乎保持恒定的表面压力，并且随着对柔性蛋白质的吸附增加，吸附层厚度显着增加。