Department of Chemistry, University of Massachusetts, Amherst, 01003, United States.
Adv Colloid Interface Sci. 2011 Sep 14;167(1-2):24-37. doi: 10.1016/j.cis.2011.06.006. Epub 2011 Jul 8.
Polyelectrolyte-colloid coacervation could be viewed as a sub-category of complex coacervation, but is unique in (1) retaining the structure and properties of the colloid, and (2) reducing the heterogeneity and configurational complexity of polyelectrolyte-polyelectrolyte (PE-PE) systems. Interest in protein-polyelectrolyte coacervates arises from preservation of biofunctionality; in addition, the geometric and charge isotropy of micelles allows for better comparison with theory, taking into account the central role of colloid charge density. In the context of these two systems, we describe critical conditions for complex formation and for coacervation with regard to colloid and polyelectrolyte charge densities, ionic strength, PE molecular weight (MW), and stoichiometry; and effects of temperature and shear, which are unique to the PE-micelle systems. The coacervation process is discussed in terms of theoretical treatments and models, as supported by experimental findings. We point out how soluble aggregates, subject to various equilibria and disproportionation effects, can self-assemble leading to heterogeneity in macroscopically homogeneous coacervates, on multiple length scales.
聚电解质-胶体共凝聚可以被视为复杂共凝聚的一个子类，但它具有独特的特点：(1)保留胶体的结构和性质，(2)降低聚电解质-聚电解质（PE-PE）系统的不均匀性和构象复杂性。人们对蛋白质-聚电解质共凝聚体的兴趣源于对生物功能的保留；此外，胶束的几何和电荷各向同性允许更好地与理论进行比较，考虑到胶体电荷密度的核心作用。在这两个系统的背景下，我们描述了复杂形成和共凝聚的关键条件，涉及胶体和聚电解质电荷密度、离子强度、PE 分子量 (MW) 和化学计量比；以及温度和剪切的影响，这些因素是聚电解质-胶束系统所特有的。共凝聚过程是根据理论处理和模型进行讨论的，实验结果支持了这些理论和模型。我们指出了在不同的平衡和歧化效应下，可溶性聚集体如何自组装，导致宏观上均匀的共凝聚物在多个长度尺度上的不均匀性。
