Direct measurements reveal non-Markovian fluctuations of DNA threading through a solid-state nanopore

Nicholas A. W. Bell; Ulrich F. Keyser

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arXiv · 1607.04612

Direct measurements reveal non-Markovian fluctuations of DNA threading through a solid-state nanopore

Nicholas A. W. Bell·Ulrich F. Keyser

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Abstract

The threading of a polymer chain through a small pore is a classic problem in polymer dynamics and underlies nanopore sensing technology. However important experimental aspects of the polymer motion in a solid-state nanopore, such as an accurate measurement of the velocity variation during translocation, have remained elusive. In this work we analysed the translocation through conical quartz nanopores of a 7 kbp DNA double-strand labelled with six markers equally spaced along its contour. These markers, constructed from DNA hairpins, give direct experimental access to the translocation dynamics. On average we measure a 5% reduction in velocity during the translocation. We also find a striking correlation in velocity fluctuations with a decay constant of 100s of {\mu}s. These results shed light on hitherto unresolved problems in the dynamics of DNA translocation and provide guidance for experiments seeking to determine positional information along a DNA strand.

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Nicholas A. W. Bell, Ulrich F. Keyser. 2016-07-15. Direct measurements reveal non-Markovian fluctuations of DNA threading through a solid-state nanopore. https://arxiv.org/abs/1607.04612

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