Spatially controlled DNA unzipping by microfluidic interface positioning on a molecule perpendicular to a multicomponent flow.

A DNA molecule is rotated under a transversal electric field to be perpendicular to a longitudinal, multicomponent microfluidic flow. Positioning the interface allows us to control DNA unzipping with spatio-temporal resolution. This demonstrates that a microfluidic gradient can be applied at the single molecule level for a dynamic intramolecular stimulation.