Thomas LaBean of Duke University and his colleagues first assembled tiles from synthetic DNA molecules, which they used as building blocks. Under the right chemical conditions, these tiles arrange themselves into tubes that measure just 25 nanometers in diameter and up to 20 microns in length. (The new process improves on previous assembly methods, which resulted in tubes of greatly varying lengths and some leftover tiles.) The scientists then created smooth, uniform silver nanowires from the tubes through a two-step chemical reaction.
The benefit of utilizing DNA to assemble nanotechnology lies in its specificity. Because DNA bonds according to well-understood base-pairing rules, the scientists hope to exploit it in order to place nanowires at precise locations on a relatively large chip without having to directly manipulate them.