Gupta Damini, Sheats Julian, Muralidhar Abhiram, Miller Jeremy J, Huang Derek E, Mahshid Sara, Dorfman Kevin D, Reisner Walter
Department of Chemical Engineering and Materials Science, University of Minnesota - Twin Cities, 421 Washington Ave SE, Minneapolis, Minnesota 55455, USA.
Physics Department, McGill University, 3600 rue University, Montreal, Quebec H3A 2T8, Canada.
J Chem Phys. 2014 Jun 7;140(21):214901. doi: 10.1063/1.4879515.
We have used a combination of fluorescence microscopy experiments and Pruned Enriched Rosenbluth Method simulations of a discrete wormlike chain model to measure the mean extension and the variance in the mean extension of λ-DNA in 100 nm deep nanochannels with widths ranging from 100 nm to 1000 nm in discrete 100 nm steps. The mean extension is only weakly affected by the channel aspect ratio. In contrast, the fluctuations of the chain extension qualitatively differ between rectangular channels and square channels with the same cross-sectional area, owing to the "mixing" of different confinement regimes in the rectangular channels. The agreement between experiment and simulation is very good, using the extension due to intercalation as the only adjustable parameter.
我们结合荧光显微镜实验和离散蠕虫状链模型的剪枝富集罗森布鲁斯方法模拟，以测量λ-DNA在深度为100 nm、宽度在100 nm至1000 nm之间且以100 nm为离散步长的纳米通道中的平均伸展长度以及平均伸展长度的方差。平均伸展长度仅受通道纵横比的微弱影响。相比之下，由于矩形通道中不同限制区域的“混合”，具有相同横截面积的矩形通道和方形通道中链伸展的波动在性质上有所不同。以嵌入引起的伸展作为唯一可调参数时，实验与模拟之间的吻合度非常好。
