Diehl A, Kuhn P S
Departamento de Física, Instituto de Física e Matemática, Universidade Federal de Pelotas, Caixa Postal 354, CEP 96010-900, Pelotas, RS, Brazil.
Phys Rev E Stat Nonlin Soft Matter Phys. 2009 Jan;79(1 Pt 1):011805. doi: 10.1103/PhysRevE.79.011805. Epub 2009 Jan 22.
We study the conformation of polyelectrolyte-surfactant complexes in the presence of monovalent salt. A simple model for the formation of these structures is presented in the framework of the Debye-Hückel-Bjerrum-Manning and Flory theories, with the hydrophobic interactions between the hydrocarbon tails of surfactant molecules treated in the spirit of van der Waals theory as an effective attraction. The extension of the polyelectrolyte-surfactant complexes is analyzed as a function of the salt concentration and a discrete conformational transition between a compact globule and an elongated coil is found, in agreement with experimental results for the unfolding transition of a DNA-cationic surfactant complex.
我们研究了单价盐存在下聚电解质 - 表面活性剂复合物的构象。在德拜 - 休克尔 - 比耶鲁姆 - 曼宁理论和弗洛里理论的框架内，提出了一个形成这些结构的简单模型，其中表面活性剂分子烃链尾部之间的疏水相互作用按照范德华理论的思路被视为一种有效吸引力。分析了聚电解质 - 表面活性剂复合物的伸展情况与盐浓度的函数关系，发现了在紧密球体和细长线圈之间存在离散的构象转变，这与DNA - 阳离子表面活性剂复合物解折叠转变的实验结果一致。
