Annaka Masahiko, Okamoto Masahiro, Matsuura Toyoaki, Hara Yoshiaki, Sasaki Sigeo
Department of Chemistry, Faculty of Sciences, Kyushu University, 6-10-1, Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
J Phys Chem B. 2007 Jul 26;111(29):8411-8. doi: 10.1021/jp067324f. Epub 2007 May 31.
The salt effects on phase equilibrium and dynamical properties of pig vitreous body was studied by the macroscopic observation of the swelling behavior and dynamic light scattering under various conditions. It was found that the vitreous body collapses with maintaining the shape when the concentrations of salts (NaCl, CaCl2, and MgCl2) were changed. From the observations of the dynamics of light scattered by the pig vitreous body, intensity autocorrelation functions that revealed two diffusion coefficients, Dfast and Dslow were obtained. We developed the theory for describing the density fluctuation of the entities in the vitreous gel system with sodium hyaluronate filled in the meshes of the collagen fiber network. The dynamics of collagen and sodium hyaluronate explains two relaxation modes of the fluctuation. The diffusion coefficient of collagen obtained from Dfast and Dslow is very close to that in aqueous solution, which suggests the vitreous body is in the swollen state. Divergent behavior in the measured total scattered light intensities and diffusion coefficients upon varying the concentration of salt was observed. Namely, a slowing down of the dynamic modes accompanied by increased "static" scattered intensities was observed. This is indicative of the occurrence of a phase transition upon salt concentration.
通过在各种条件下对猪玻璃体膨胀行为的宏观观察以及动态光散射，研究了盐对猪玻璃体相平衡和动力学性质的影响。研究发现，当改变盐（氯化钠、氯化钙和氯化镁）的浓度时，玻璃体在保持形状的同时会发生塌陷。通过对猪玻璃体散射光动力学的观察，获得了揭示两个扩散系数Dfast和Dslow的强度自相关函数。我们建立了一个理论，用于描述填充在胶原纤维网络网眼中的透明质酸钠的玻璃体凝胶系统中实体的密度涨落。胶原蛋白和透明质酸钠的动力学解释了涨落的两种弛豫模式。从Dfast和Dslow得到的胶原蛋白扩散系数与水溶液中的非常接近，这表明玻璃体处于肿胀状态。观察到在改变盐浓度时，测量的总散射光强度和扩散系数出现发散行为。也就是说，观察到动态模式减慢，同时“静态”散射强度增加。这表明在盐浓度变化时发生了相变。
