Self-Assembly of Novel Mesoscopic Structures using DNA-programmed Interactions

该项目将开发技术，以工程悬浮的DNA标记的微球，将自发地自组装成新的，三维胶体晶体结构。 球体的自组装将由大量结合到其表面的非常弱缔合的单链DNA分子诱导的短程可逆吸引相互作用驱动。 重要的是，这种相互作用是由DNA分子的序列决定的，从而能够产生二元和三元胶体混合物，其中不同球体群体之间的相互作用在大小和符号上是独立可编程的，吸引或排斥。 这种灵活性将允许创建以前未观察到的合金相，如BCC，SC和类金刚石相，这些相作为原子晶体和相变的模型系统以及光子带隙晶体的3D模板都很有意义。 从长远来看，目标是生产和传播自动化设计工具，用于生成产生所需晶体结构的DNA配方。 此外，这项工作将为化学工程专业的学生提供出色的机会，从事基础材料研究，以及掌握从显微镜到计算基因组学的技术。凝聚态物理学中的一个主要突出主题涉及晶体如何形成和生长，以及是什么决定了它们的原子结构。 许多实验使用漂浮在水中的微球来模拟原子过程-像原子一样，它们会自发结晶成有序的3D阵列，但与原子不同的是，这个过程在简单的显微镜下是可见的。 拟议的研究将开发新的方法，通过使用附着在其表面的DNA分子将这些球体粘在一起形成新型晶体结构。 当两个球体带着互补的双螺旋的一半走到一起时，分子会拉上拉链，把球体拉在一起。 除了具有根本性的意义外，这些新的合金状晶体在技术上还可以用作所谓光子带隙材料的模板，一些研究人员认为这将导致更高效的激光器以及更快的计算机和电信系统。 此外，这项工作将为化学工程专业的学生提供出色的机会，从事基础材料研究，以及从显微镜到计算基因组学的掌握技术。

This project will develop techniques to engineer suspensions of DNA-labeled microspheres that will spontaneously self-assemble into novel, 3-dimensional colloidal crystal structures. The self-assembly of the spheres will be driven by a short-ranged, reversible attractive interaction induced by large numbers of very weakly associating single-stranded DNA molecules bound to their surface. Importantly, this interaction is determined by the sequence of the DNA molecules--enabling the creation of binary and ternary colloidal mixtures where the interactions between the different sphere populations are independently programmable in magnitude and sign, attractive or repulsive. This flexibility will permit the creation of previously unobserved alloy phases, such as BCC, SC and diamond-like phases, which are of interest both as model systems for atomic crystals and phase transitions as well as 3D templates for photonic bandgap crystals. Over the long-term, the goal is to produce and disseminate automated design tools for generating DNA recipes yielding a desired crystal structure. In addition, this work will provide chemical engineering students outstanding opportunities to pursue basic materials research, as well as master techniques ranging from microscopy to computational genomics.A major outstanding topic in Condensed Matter Physics concerns how crystals form and grow, and what determines their atomic structure. Many experiments use microspheres floating in water to model atomic processes--like atoms they will spontaneously crystallize into ordered 3D arrays, but unlike atoms, the process is visible under a simple microscope. The proposed research will develop new methods for sticking these spheres together into new types of crystal structures by using DNA molecules attached to their surfaces. When two spheres come together bearing complementary halves of the double helix, the molecules will zip up pulling the spheres together. Besides being of fundamental interest, these new alloy-like crystals will be technologically useful as templates for so-called photonic bandgap materials, which some researchers believe will lead to more efficient lasers as well as faster computers and telecommunication systems. In addition, this work will provide chemical engineering students outstanding opportunities to pursue basic materials research, as well as master techniques ranging from microscopy to computational genomics.