Nano (not!): Built for the 1958 Brussels World's Fair, this model of a body-centred cubic crystal is similar to the nano crystal created with DNA except it is magnified 165 billion times.Courtesy John Kerno

First step toward three-dimensional catalytic, magnetic, and/or optical nanomaterials

Assembling structures that are 1000 times smaller than a human hair is difficult. One technique that works is known as "self assembly". A random mixture of microscopic parts can be coaxed into assembling spontaneously into a desired structure by attaching appropriate segments of DNA to various parts. Complementary DNA strands want to "pair up". This is how nano structures are assembled in living organisms.

"researchers at the U.S. Department of Energy's Brookhaven National Laboratory have for the first time used DNA to guide the creation of three-dimensional, ordered, crystalline structures of nanoparticles.

Nanomaterials: Golden handshake

The team from Brookhaven and another group from Northwestern University in Evanston, US, both started with tiny spheres of gold around 10 nanometres across, and attached short strands of DNA. By varying the length of the DNA strands, their flexibility,and the types of sticky ends, they are working toward reliably binding them together in particular ways. This is the first step toward building three-dimensional catalytic, magnetic, and/or optical nanomaterials.

Sources:

• "DNA-programmable nanoparticle crystallization" Nature; abstract (Jan 31, 2008)
• New Scientist Tech: source article
• Brookhaven National Laboratory News release from