Manipulation of Conductivity in DNA
M. Tinkham and H. Park
a) Topographic image of a DNA strand; b) Phase shift image indicating that the conductivity
has increased by several orders of magnitude compared to pure l-DNA.
In previous work using a novel contactless scanning conductance method, we
imaged the conductivity of l-DNA strands and found
that they are insulating, apparently ruling out their use in “wiring” nano-circuits.
Recently, we have discovered that by substituting Zn2+ ions into
the base pairs of l-DNA the conductivity of the
DNA strand increased sufficiently to appear on our scanning conductance probe.
Further work will be needed to explore possible applications of such DNA with enhanced conductivity.