Dynamics of ion migration in nanopores and the effect of DNA-ion interaction.
Dynamics of ion migration in nanopores and the effect of DNA-ion interaction.
复制标题
DOI：
10.1021/jp111111u
复制
发表时间：
2011-09-15
期刊：
影响因子：
--
通讯作者：
Cui S
中科院分区：
文献类型：
--
作者：
Cui S
我们已经进行了布朗动力学计算，以研究DNA-离子相互作用对纳米孔中离子输运的影响。我们计算了在纳米孔中存在DNA的情况下单价离子的自扩散系数，并与通过开孔的自扩散系数进行了比较，即，没有DNA的存在。我们发现共离子的自扩散系数基本上不受DNA的影响。另一方面，反离子的自扩散系数根据离子浓度而显著降低。在高离子浓度下，大约1 M，DNA对反扩散的影响相对较小，导致反扩散系数略有降低。在几mM的低浓度下，效果大得多，导致反扩散系数降低约2.5倍。的自扩散的反离子的变化是很好地描述占从两个组件的贡献：吸附的反离子和自由的反离子。详细的动态的DNA-抗衡离子相互作用的特征在于由不同长度的瞬态吸附时间的抗衡离子的DNA电荷位点和与环境的交换率。吸附时间的这种变化归因于离子电屏蔽效应，而离子电屏蔽效应又取决于离子浓度。
We have carried out Brownian Dynamics calculations to investigate the effect of DNA-ion interaction on ion transport in a nanopore. We calculated the self-diffusion coefficient of monovalent ions in the presence of DNA in a nanopore and compared with that through an open pore, i.e., without the presence of DNA. We find that the self-diffusion coefficient of the coions is essentially unaffected by the DNA. The self-diffusion coefficient of the counterions, on the other hand, is significantly reduced depending on the ion concentration. At high ion concentration, around 1 M, the effect of DNA on counterion diffusion is relatively small, causing a slight reduction in counterion diffusion coefficient. At low concentration of a few mM, the effect is much larger, resulting in a reduction in counterion diffusion coefficient by about a factor 2.5. The variation in the self-diffusion of the counterion is well described by accounting for the contributions from two components: the adsorbed counterions; and the free counterions. Detailed dynamics of the DNA-counterion interaction is characterized by the varying length of the transient adsorption time of the counterions to the DNA charge sites and the exchange rate with the environment. This variation in counterion adsorption time is attributed to ionic electric screening effect, which is in turn determined by the ion concentration.
登录
查看更多内容
影响因子：
19.6
作者：
Keyser, Ulrich F.;Koeleman, Bernard N.;Dekker, Cees
通讯作者：
Dekker, Cees
影响因子：
10.8
作者：
Chang, H;Kosari, F;Bashir, R
通讯作者：
Bashir, R
影响因子：
2.9
作者：
HINGERTY, BE;RITCHIE, RH;TURNER, JE
通讯作者：
TURNER, JE
DOI：
10.1073/pnas.93.24.13770
发表时间：
1996-11-26
影响因子：
11.1
作者：
Kasianowicz, JJ;Brandin, E;Deamer, DW
通讯作者：
Deamer, DW
DOI：
10.1021/jp909564d
发表时间：
2010-02-11
期刊：
The journal of physical chemistry. B
影响因子：
--
作者：
Cui S
通讯作者：
Cui S