Affiliation:
1. Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, MA 01003, USA.
Abstract
Linear DNA molecules are visualized while undergoing Brownian motion inside media patterned with molecular-sized spatial constraints. The media, prepared by colloidal templating, trap the macromolecules within a two-dimensional array of spherical cavities interconnected by circular holes. Across a broad DNA size range, diffusion does not proceed by the familiar mechanisms of reptation or sieving. Rather, because of their inherent flexibility, DNA molecules strongly localize in cavities and only sporadically “jump” through holes. Jumping closely follows Poisson statistics. By reducing DNA's configurational freedom, the holes act as molecular weight–dependent entropic barriers. Sterically constrained macromolecular diffusion underlies many separation methods and assumes an important role in intracellular and extracellular transport.
Publisher
American Association for the Advancement of Science (AAAS)
Cited by
142 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献