Macfarlane Robert J, Thaner Ryan V, Brown Keith A, Zhang Jian, Lee Byeongdu, Nguyen SonBinh T, Mirkin Chad A
Department of Chemistry and International Institute for Nanotechnology, Northwestern University, Evanston, IL 60208; and.
X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439.
Proc Natl Acad Sci U S A. 2014 Oct 21;111(42):14995-5000. doi: 10.1073/pnas.1416489111. Epub 2014 Oct 8.
If a solution of DNA-coated nanoparticles is allowed to crystallize, the thermodynamic structure can be predicted by a set of structural design rules analogous to Pauling's rules for ionic crystallization. The details of the crystallization process, however, have proved more difficult to characterize as they depend on a complex interplay of many factors. Here, we report that this crystallization process is dictated by the individual DNA bonds and that the effect of changing structural or environmental conditions can be understood by considering the effect of these parameters on free oligonucleotides. Specifically, we observed the reorganization of nanoparticle superlattices using time-resolved synchrotron small-angle X-ray scattering in systems with different DNA sequences, salt concentrations, and densities of DNA linkers on the surface of the nanoparticles. The agreement between bulk crystallization and the behavior of free oligonucleotides may bear important consequences for constructing novel classes of crystals and incorporating new interparticle bonds in a rational manner.
如果让DNA包覆的纳米颗粒溶液结晶，其热力学结构可通过一组类似于鲍林离子结晶规则的结构设计规则来预测。然而，结晶过程的细节被证明更难描述，因为它们取决于许多因素的复杂相互作用。在此，我们报告该结晶过程由单个DNA键决定，并且通过考虑这些参数对游离寡核苷酸的影响，可以理解改变结构或环境条件的作用。具体而言，我们在具有不同DNA序列、盐浓度以及纳米颗粒表面DNA连接体密度的系统中，利用时间分辨同步加速器小角X射线散射观察了纳米颗粒超晶格的重组。体相结晶与游离寡核苷酸行为之间的一致性可能对构建新型晶体类别以及合理引入新的颗粒间键具有重要意义。
