Nano Letters, 2010, 10 (3), pages 765-772
Derek Stein, Zeno Deurvorst, Frank H. J. van der Heyden, Wiepke J. A. Koopmans, Alan Gabel and Cees Dekker. Kavli Institute of NanoScience, Delft University of Technology, Delft, The Netherlands
DNA molecules can be concentrated in a narrow region of a nanochannel when driven electrokinetically in submillimolar salt solutions. Transport experiments and theoretical modeling reveal the interplay of electrophoresis, electro-osmosis, and the unique statistical properties of confined polymers that lead to DNA aggregation. A finite conductance through the bulk of the device also plays a crucial role by influencing the electric fields in the nanochannel. We build on this understanding by demonstrating how a nanofluidic device with integrated electrodes can preconcentrate DNA at selected locations and at physiological salt concentrations that are relevant to lab-on-a-chip applications.