The entropic cost of polymer confinement.
The entropic cost of polymer confinement.
复制标题
聚合物限制的熵成本。
DOI：
10.1021/jp302807r
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Harvey,StephenC
中科院分区：
文献类型：
--
作者：
Smyda,MarkR;Harvey,StephenC
The confinement of a polymer into a small space is thermodynamically unfavorable because of the reduction in the number of conformational states. The entropic penalty affects a variety of biological processes, and it plays an important role in polymer transport properties and in microfluidic devices. We determine the entropic penalty for the confinement of elastic polymer of persistence lengthPin the long-chain limit. We examine three geometries: (1) parallel planes separated by a distanced(a slit); (2) a circular tube of diameterd; and (3) a sphere of diameterd. We first consider infinitely thin (ideal) chains. Asd/Pdrops from 100 to 0.01,TΔSrises from ∼5 × 10–4kTto ∼30kTper persistence length for cases (1) and (2), with the entropic penalty for case (2) being consistently about twice that for case (1).TΔSis ∼5kTper persistence length for confinement to a sphere whend=P, about twice the value predicted by mean field theory. For all three geometries, in the limitd/P≫ 1, the asymptotic behavior of ΔSvsdis consistent with thed-2behavior predicted by theory. In the limitd/P≪ 1, the scaling of ΔSfor slits and tubes is also consistent with earlier predictions (d–2/3). Finally, we treat volume exclusion effects, examining chains of diameterD> 0. Confinement to a narrow slit or tube (d/P≪ 1) has the same entropic penalty as that for an ideal chain in a slit or tube withd′ = d – D; in the weak confinement regime (d/P≫ 1), the entropic penalties are significantly larger than those for infinitely thin chains. When a chain of finite diameter is forced into a sphere or other closed cavity, the entropic confinement penalty rises without limit because there are no configurations available to the chain once its volume exceeds that of the cavity.
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影响因子：
5.5
作者：
T. Sakaue;E. Raphael
通讯作者：
T. Sakaue;E. Raphael
病毒组装：分子建模视角。
DOI：
10.1039/b912884k
发表时间：
2009
期刊：
Physical chemistry chemical physics : PCCP
影响因子：
--
作者：
Harvey,StephenC;Petrov,AntonS;Devkota,Batsal;Boz,MustafaBurak
通讯作者：
Boz,MustafaBurak
影响因子：
2.9
作者：
SCHELLMAN, JA
通讯作者：
SCHELLMAN, JA
影响因子：
3.4
作者：
Locker, C. Rebecca;Fuller, Stephen D.;Harvey, Stephen C.
通讯作者：
Harvey, Stephen C.
影响因子：
56.9
作者：
Han, J;Craighead, HG
通讯作者：
Craighead, HG