Modeling the conductance and DNA blockade of solid-state nanopores
Modeling the conductance and DNA blockade of solid-state nanopores
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DOI：
10.1088/0957-4484/22/31/315101
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发表时间：
2011-08-05
期刊：
影响因子：
3.5
通讯作者：
Dekker, Cees
中科院分区：
文献类型：
--
作者：
Kowalczyk, Stefan W.;Grosberg, Alexander Y.;Dekker, Cees
我们给出了直径为5-100 nm的固体纳米孔的离子电导G的测量和理论模型，其中包括插入和不插入DNA的情况。首先，我们证明了包括访问电阻来描述电导是必要的，特别是对于较大的孔直径。然后，我们给出了沙漏形孔的G的精确解，它与我们的测量结果非常吻合，没有任何可调的参数，这是对柱面近似的改进。随后，我们讨论了由于DNA分子插入到孔中而导致的电导阻塞Delta G，我们通过实验研究了它与孔直径的关系。我们发现，Delta G随孔直径的增大而减小，这与先前预测的Delta G恒定的模型相反。我们比较了三种Delta G模型，它们都与我们的实验数据很好地吻合。
We present measurements and theoretical modeling of the ionic conductance G of solid-state nanopores with 5-100 nm diameters, with and without DNA inserted into the pore. First, we show that it is essential to include access resistance to describe the conductance, in particular for larger pore diameters. We then present an exact solution for G of an hourglass-shaped pore, which agrees very well with our measurements without any adjustable parameters, and which is an improvement over the cylindrical approximation. Subsequently we discuss the conductance blockade Delta G due to the insertion of a DNA molecule into the pore, which we study experimentally as a function of pore diameter. We find that Delta G decreases with pore diameter, contrary to the predictions of earlier models that forecasted a constant Delta G. We compare three models for Delta G, all of which provide good agreement with our experimental data.