Nanotech Gadgets to Be Built by Algae?

<< Back to Page 1   Page 2 of 2

(Newtonian physics denotes well-known forces like gravity, while quantum mechanics describes laws of physics that apply at very small scales, such as those found in atoms.)

At the nanoscale, for example, the metal germanium glows blue when energy is applied to it. This has a host of applications in electronic and medical imaging technologies, Rorrer said.

The process to incorporate germanium nanoparticles in silica is "doable but difficult with existing technology," the scientist said.

The conventional process involves vaporizing a germanium crystal in a vacuum with a high-energy laser beam and coaxing the vaporized atoms to glom onto a silica surface.

"That has to be done at a high temperature [and] at a high vacuum and [with] all the equipment associated with the control of that," Rorrer said. "We do essentially the same thing by growing living organisms in a vat."

The trick for Rorrer and his Oregon State University colleague, Chih-hung Chang, is to add just enough dissolved metal to the vat to allow the diatoms to absorb it without dying.

To date "the concept for germanium incorporation has been proven," Chang said. "We will work on incorporating other metals very soon."

Another advantage to using diatoms, Rorrer said, is that when the algae divide, they make a perfect copy of themselves, meaning "we can make a gazillion of these, and they are all the same."

Shapes

In addition to the ability of the diatoms to absorb these metals and create nanostructured materials, each diatom species makes shells with unique designs. And there are tens of thousands of diatom species.

Which means there are "tens of thousands of micro-templates," Rorrer said. "Some have holes, some ribs, some oval, some square—and all the microfabrication has been done by the organisms. We just put additional material on it."

In the future, the researchers hope they can use these diatoms to make intricate designs at the microscale that are currently not possible with existing technology.

To find the appropriate template, all a researcher would need is a searchable database of natural diatom designs. Genetic engineering may also one day make it possible to control diatom design.

Free E-Mail News Updates
Sign up for our Inside National Geographic newsletter. Every two weeks we'll send you our top stories and pictures (see sample).

<< Back to Page 1   Page 2 of 2


SOURCES AND RELATED WEB SITES

ADVERTISEMENT

NATIONAL GEOGRAPHIC'S PHOTO OF THE DAY

NEWS FEEDS     After installing a news reader, click on this icon to download National Geographic News's XML/RSS feed.   After installing a news reader, click on this icon to download National Geographic News's XML/RSS feed.

Get our news delivered directly to your desktop—free.
How to Use XML or RSS

National Geographic Daily News To-Go

Listen to your favorite National Geographic news daily, anytime, anywhere from your mobile phone. No wires or syncing. Download Stitcher free today.
Click here to get 12 months of National Geographic Magazine for $15.