Self-Assembly of Bifunctional Patchy Particles with Anisotropic Shape into Polymers Chains: Theory, Simulations, and Experiments
Self-Assembly of Bifunctional Patchy Particles with Anisotropic Shape into Polymers Chains: Theory, Simulations, and Experiments
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DOI：
10.1021/ma201962x
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发表时间：
2012-01-24
期刊：
影响因子：
5.5
通讯作者：
Sciortino, Francesco
中科院分区：
文献类型：
--
作者：
De Michele, Cristiano;Bellini, Tommaso;Sciortino, Francesco
已知短至6个碱基对的短平端DNA双链体的浓缩溶液有序地进入双相液晶相。这种自组装是由于双链末端之间的堆叠相互作用，促进它们聚集成具有显著持久长度的多分散链。实验表明，液晶相的形成取决于双链体长度的临界体积分数以上。我们介绍和调查，通过数值模拟，一个粗粒度的DNA双螺旋模型。每个双链体被表示为硬准圆柱体，其基部被两个相同的反应位点装饰。终端点之间的堆垛相互作用用短程方阱势模拟。我们比较的数值计算结果与预测的基础上的自由能泛函，并找到满意的定量匹配的各向同性相边界和系统结构。数值和理论结果与实验结果的比较证实，DNA双链体的自组装可以通过圆柱形粒子的平衡聚合适当建模。这一认识使我们能够估计堆积能。
Concentrated solutions of short blunt-ended DNA duplexes, as short as 6 base pairs, are known to order into the nematic liquid crystal phases. This self-assembly is due to the stacking interactions between duplex terminals that promotes their aggregation into polydisperse chains with a significant persistence length. Experiments show that liquid crystal phases form above a critical volume fraction depending on the duplex length. We introduce and investigate via numerical simulations, a coarse-grained model of DNA double-helical duplexes. Each duplex is represented as an hard quasi-cylinder whose bases are decorated with two identical reactive sites. The stacking interaction between terminal sites is modeled short-range square-well potential. We compare the numerical results with predictions based on a free energy functional and find satisfactory quantitative matching of the isotropic nematic phase boundary and of the system structure. Comparison of numerical and theoretical results with experimental findings confirm that the DNA duplex self-assembly can be properly modeled via equilibrium polymerization of cylindrical particles. This insight enables us to estimate the stacking energy.