Department of Chemical Engineering and Materials Science, University of Minnesota-Twin Cities, 421 Washington Ave. SE, Minneapolis, Minnesota 55455, USA.
Biomicrofluidics. 2013 Mar 1;7(2):24102. doi: 10.1063/1.4794371. eCollection 2013.
Using Monte Carlo simulations of a touching-bead model of double-stranded DNA, we show that DNA extension is enhanced in isosceles triangular nanochannels (relative to a circular nanochannel of the same effective size) due to entropic depletion in the channel corners. The extent of the enhanced extension depends non-monotonically on both the accessible area of the nanochannel and the apex angle of the triangle. We also develop a metric to quantify the extent of entropic depletion, thereby collapsing the extension data for circular, square, and various triangular nanochannels onto a single master curve for channel sizes in the transition between the Odijk and de Gennes regimes.
利用双链 DNA 触珠模型的蒙特卡罗模拟，我们表明，由于在通道拐角处的熵耗竭，等腰三角形纳米通道（相对于相同有效尺寸的圆形纳米通道）中的 DNA 延伸得到增强。增强的延伸程度与纳米通道的可及面积和三角形的顶角非单调相关。我们还开发了一种度量标准来量化熵耗竭的程度，从而将圆形、方形和各种三角形纳米通道的延伸数据压缩到 Odijk 和 de Gennes 区域之间的通道尺寸的单个主曲线上。
