Electrophoretic separation of large DNAs using steric confinement
Résumé
We report a new method for electrophoresis 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 thickness followed by a sharp transition to the bulk behaviour (no separation) at a thickness of about 4Rg (Rg the radius of gyration in bulk). We present tentative explanations of our original observations.