Randall Greg C, Doyle Patrick S
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Phys Rev Lett. 2004 Jul 30;93(5):058102. doi: 10.1103/PhysRevLett.93.058102. Epub 2004 Jul 29.
We study the dynamics of single DNA molecules driven by an electric field into a stationary obstacle. These collisions are broadly classified as "hook" and "roll-off" events. We show that obstacle-induced electric field gradients stretch impacting DNA and thus greatly influence the hooking probability. Consequently, in addition to collision geometry, determination of the hooking probability depends on the Deborah number (De) for 0.5<De<40. Individual DNA impact dynamics are highly configuration sensitive, characteristic of polymers in elongational flows and fields.
我们研究了在电场驱动下单条DNA分子与固定障碍物的碰撞动力学。这些碰撞大致可分为“钩挂”和“滚落”事件。我们发现障碍物诱导的电场梯度会拉伸碰撞中的DNA，从而极大地影响钩挂概率。因此，除了碰撞几何形状外，钩挂概率的确定还取决于Deborah数（De），其中0.5<De<40。单个DNA的碰撞动力学对构型高度敏感，这是聚合物在拉伸流和电场中的特性。
