Dynamic light scattering and 31P NMR study of the self-assembly of deoxyguanosine 5′-monophosphate:: the effect of added salt
Dynamic light scattering and 31P NMR study of the self-assembly of deoxyguanosine 5′-monophosphate:: the effect of added salt
复制标题
DOI：
10.1140/epje/e2004-00037-0
复制
发表时间：
2004-01-01
影响因子：
1.8
通讯作者：
Mariani, P
中科院分区：
文献类型：
--
作者：
Spindler, L;Drevensek-Olenik, I;Mariani, P
通过 P-31 NMR 光谱和动态光散射 (DLS) 研究了脱氧鸟苷 5'-单磷酸在各向同性水溶液中的自组装和动力学性质。所有溶液都具有相同的 c = 4 wt% 鸟苷浓度，而添加的 KCl 摩尔浓度范围为 0 至 1.5 M。 P-31 NMR 测量表明，钾离子强烈增强鸟苷四聚体的堆积过程，直到在 0.1 M KCl 时达到饱和，超过 70% 的分子聚集。偏振光散射揭示了自组装堆栈的平移动力学产生的快速弛豫模式的存在。该模式的扩散系数显示出对添加盐的摩尔浓度的强烈依赖性，这可以用聚电解质溶液的耦合模式和抗衡离子缩合理论来描述。去偏振光散射揭示了自组装堆叠的旋转动力学，随着添加盐含量的增加，其旋转速度明显减慢。
Self-assembling and dynamical properties of deoxyguanosine 5'-monophosphate in isotropic aqueous solutions were studied by P-31 NMR spectroscopy and dynamic light scattering (DLS). All solutions had the same c = 4 wt% guanosine concentration, while the added KCl molarity ranged from 0 to 1.5 M. P-31 NMR measurements show that potassium ions strongly enhance the stacking process of guanosine tetramers until a saturation is reached at 0.1 M KCl with more than 70% of the molecules aggregated. Polarized light scattering reveals the presence of a fast relaxation mode that arises from the translational dynamics of the self-assembled stacks. The diffusion coefficient of this mode shows a strong dependence on molarity of added salt, which can be described in terms of the coupled mode and counterion condensation theories for polyelectrolyte solutions. Depolarized light scattering reveals the rotational dynamics of the self-assembled stacks which exhibits a pronounced slowing down with increasing the added salt content.