Section on Tissue Biophysics and Biomimetics, Program in Pediatric Imaging and Tissue Sciences, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 13 South Drive, Bethesda, Maryland 20892, United States.
J Phys Chem B. 2010 Dec 2;114(47):15445-50. doi: 10.1021/jp106578f. Epub 2010 Nov 4.
In solutions of the charged semirigid biopolymer hyaluronic acid in salt-free conditions, the diffusion coefficient D(NSE) measured at high transfer momentum q by neutron spin echo is more than an order of magnitude smaller than that determined by dynamic light scattering, D(DLS). This behavior contrasts with neutral polymer solutions. With increasing salt content, D(DLS) approaches D(NSE), which is independent of ionic strength. Contrary to theoretical expectation, the ion-polymer coupling, which dominates the low q dynamics of polyelectrolyte solutions, already breaks down at distance scales greater than the Debye-Hückel length.
在中性盐条件下的带电荷的半刚性生物聚合物透明质酸溶液中，通过中子自旋回波测量的高转移动量 q 下的扩散系数 D（NSE）比动态光散射（D（DLS））确定的扩散系数小一个数量级以上。这种行为与中性聚合物溶液相反。随着盐含量的增加，D（DLS）趋近于与离子强度无关的 D（NSE）。与理论预期相反，在大于德拜-休克尔长度的距离尺度上，主导聚电解质溶液低 q 动力学的离子-聚合物耦合已经失效。
