Migration of DNA Due to a Combination of Parallel Pressure Gradient and External Electric Field

A combination of a parallel electric field and pressure gradient can cause DNA molecules to migrate transverse to the field lines. We hypothesize that the phenomenon is due to an electrically induced velocity disturbance. A Brownian Dynamics method for a bead-spring model of a polymer, that incorporates this electrically induced velocity disturbance, was constructed and used to predict the dynamics of DNA molecules transported through a microfluidic channel due to the pressure driven flow and electric field. To test the predictions, corresponding measurements of the probability distribution of the centers-of-mass of the DNA molecules were made in multiple channels having different cross-sectional dimensions. Preliminary simulation results match, at least qualitatively, the migration velocity, extent of migration, and entry length measured in the experiments.