DNA has unique electronic and optical properties. It has low
optical loss over a broad range of wavelengths and its
electrical resistivity is three to five orders of magnitude
lower than other polymers. Moreover, the resisitivty of the DNA
can be tweaked by changing the molecule's molecular weight.
According to Grote's team, which includes researchers from the
universities of Dayton and Cincinatti, the material could be
used to make a waveguide device that could have lower optical
losses than other polymers. "There is also promise for both
passive and active all DNA devices such as electro-optic
modulators," adds Grote.  The team obtained the DNA by treating
a mix of salmon milt and roe sacs with enzymes to remove
unwanted proteins. They then purified the material by dissolving
it in an organic solvent and filtering it through a membrane.
Finally, they used the technique of "spin deposition" to create
thin DNA films on a substrate that are stable up to 200°C. By
cross-linking DNA -- joining neighbouring mole