Swelling of biological and semiflexible polyelectrolytes
Swelling of biological and semiflexible polyelectrolytes
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生物和半柔性聚电解质的溶胀
DOI：
10.1088/0953-8984/21/42/424112
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
J. Carrillo
中科院分区：
文献类型：
--
作者：
A. Dobrynin;J. Carrillo
我们建立了半柔性(生物)聚电解质在盐溶液中溶胀的理论模型。我们的方法是基于长度尺度的分离，这允许我们将链的静电能量分成两部分，描述沿着聚合物主干的本地和远程静电相互作用。局部部分考虑了带电单体之间的相互作用，这些单体沿着聚合物主干的距离比链的持续长度短。这些静电相互作用使链持续长度重新正规化。第二部分包括沿着位于大于链持续长度的距离处的聚合物主干的远程带电对之间的静电相互作用。这些相互作用导致链膨胀。在这个方法的框架下，我们计算了有效链持续长度和链大小作为德拜屏蔽长度、链的电离度、裸持续长度和链聚合度的函数。我们得到的有效链持续长度的交叉表达式与DNA上的实验数据有很好的定量一致性。我们已经能够通过使用两个可调节的参数来拟合实验数据集：DNA电离度(α=0.15-0.17)和裸露的持续长度(Lp=40-44 nm)。
We have developed a theoretical model of swelling of semiflexible (biological) polyelectrolytes in salt solutions. Our approach is based on separation of length scales which allowed us to split a chain’s electrostatic energy into two parts that describe local and remote electrostatic interactions along the polymer backbone. The local part takes into account interactions between charged monomers that are separated by distances along the polymer backbone shorter than the chain’s persistence length. These electrostatic interactions renormalize chain persistence length. The second part includes electrostatic interactions between remote charged pairs along the polymer backbone located at distances larger than the chain persistence length. These interactions are responsible for chain swelling. In the framework of this approach we calculated effective chain persistence length and chain size as a function of the Debye screening length, chain degree of ionization, bare persistence length and chain degree of polymerization. Our crossover expression for the effective chain’s persistence length is in good quantitative agreement with the experimental data on DNA. We have been able to fit experimental datasets by using two adjustable parameters: DNA ionization degree (α = 0.15–0.17) and a bare persistence length (lp = 40–44 nm).
DOI：
10.1073/pnas.94.12.6185
发表时间：
1997-06-10
影响因子：
11.1
作者：
Baumann, CG;Smith, SB;Bustamante, C
通讯作者：
Bustamante, C
影响因子：
2.9
作者：
Lu, YJ;Weers, B;Stellwagen, NC
通讯作者：
Stellwagen, NC