Thermomechanical and Interfacial Behavior of Concentration Protein Solutions

研究综述：这项研究的目的是在分子间和分子内相互作用都很重要的条件下，对浓缩蛋白质溶液(包括蛋白质凝胶)的热力学和力学性质有一个更基本的了解。实验研究采用牛血清白蛋白作为模型体系，包括渗透压测量和渗透平衡过程中的示踪剂溶质分配。结合起来，这些数据可以用来评估溶液的非理想性和压缩压力，压缩压力是热力学模型中用来表征分子间和分子内相互作用的贡献的参数。溶液非理想性的理论分析将涉及到聚合物晶格模型的应用，例如Flory-Huggins理论，用于浓缩蛋白质溶液。分子间的吸引和排斥将使用McMillan-Mayer解理论进行建模。潜在影响：当前研究的结果以及未来研究的结果将应用于各种蛋白质分离过程的分析，在这些过程中，分子间和分子内的相互作用被认为是重要的，例如蛋白质结晶和沉淀。热力学数据和模型还将提供对液-液萃取用于蛋白质分离的深入了解。这项研究的结果也可以用于分析选择性蛋白质过滤，即使用膜超滤来根据大小分离不同分子量的蛋白质。

Research Summary: The objective of this research is to develop a more fundamental understanding of the thermodynamic and mechanical properties of concentrated protein solutions, including protein gels, under conditions where both inter- and intra-molecular interactions are important. Experimental studies, employing bovine serum albumin as a model system, will involve both osmotic pressure measurements and tracer solute partitioning during osmotic equilibrium. In combination, these data can be used to evaluate solution non-idealities and the compressive pressure, a parameter used in the thermodynamic model to characterize the contribution of both inter- and intra-molecular interactions. Theoretical analyses of solution non-idealities will involve application of polymer lattice models, for example, Flory-Huggins theory, to the concentrated protein solutions. Inter-molecular attractions and repulsions will be modelled using McMillan-Mayer solution theory. Potential Impact: The results from the current study, as well as those from future investigations, will have applications in the analysis of a variety of protein separation processes in which inter- and intra-molecular interactions are thought to be important, e.g., protein crystallization and precipitation. The thermodynamic data and models will also provide insight into the use of liquid-liquid extraction for protein separations. The results from this study can also be used to analyze selective protein filtration, the use of membrane ultrafiltration to separate proteins of differing molecular weight on the basis of size.