Fu Jianping, Yoo Juhwan, Han Jongyoon
Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Phys Rev Lett. 2006 Jul 7;97(1):018103. doi: 10.1103/PhysRevLett.97.018103.
We present an experimental study of Ogston-like sieving process of rodlike DNA in patterned periodic nanofluidic filter arrays. The electrophoretic motion of DNA through the array is described as a biased Brownian motion overcoming periodically modulated free-energy landscape. A kinetic model, constructed based on the equilibrium partitioning theory and the Kramers theory, explains the field-dependent mobility well. We further show experimental evidence of the crossover from Ogston-like sieving to entropic trapping, depending on the ratio between nanofilter constriction size and DNA size.
我们展示了在图案化周期性纳米流体过滤阵列中，棒状DNA的类奥格斯顿筛分过程的实验研究。DNA通过阵列的电泳运动被描述为克服周期性调制自由能景观的有偏布朗运动。基于平衡分配理论和克莱默斯理论构建的动力学模型，很好地解释了场依赖迁移率。我们进一步展示了根据纳米过滤器收缩尺寸与DNA尺寸之比，从类奥格斯顿筛分过渡到熵捕获的实验证据。
