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Electrophoretic separation of large DNAs using steric confinement

Jérôme Mathé·Jean-Marc Di Meglio·Bernard Tinland
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Abstract

We report an alternative method for electrophoretic separation of large DNAs using steric confinement between solid walls, without gel or obstacles. The change of electrophoretic mobility vs confinement thickness is investigated using fluorescence video microscopy. We observe separation at small confinement thicknesses followed by a transition to the bulk behaviour (no separation) at a thickness of about 4 μm (a few radii of gyration for the studied DNA chains). We present tentative explanations of our original observations.

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Jérôme Mathé, Jean-Marc Di Meglio, Bernard Tinland. 2007-07-27. Electrophoretic separation of large DNAs using steric confinement. https://arxiv.org/abs/cond-mat/0610328

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