What a flurry of activity in the nanotech world these days. Sandia researchers have unveiled a self-assembly process forming durable nanocrystal arrays, paving the way for laser light, catalysts and new memory storage. The American Chemical Society says that scientists have developed nanotube transistors operating at extremely fast microwave frequencies (2.6 GHz) that could lead to better cell phones and faster computers. At Lehigh University, researchers have found that 'nanogold' does not glitter, but its future looks bright as it turns into a semiconductor. Meanwhile, researchers at Oak Ridge National Laboratory have developed a nanobiosensor technology that gives new access to living cell's molecular processes.
Let's start with the nanobiosensor from ONRL.
Researchers at the Department of Energy's Oak Ridge National Laboratory have developed a nanoscale technology for investigating biomolecular processes in single living cells. The new technology enables researchers to monitor and study cellular signaling networks, including the first observation of programmed cell death in a single live cell.
The "nanobiosensor" allows scientists to physically probe inside a living cell without destroying it. As scientists adopt a systems approach to studying biomolecular processes, the nanobiosensor provides a valuable tool for intracellular studies that have applications ranging from medicine to national security to energy production.
||"This image shows a nanoprobe, with a tip 1,000 times finer than a human hair, penetrating a cell. The probe can enter, perform a measurement in situ and be withdrawn without destroying the cell. The nanobiosensor technology provides researchers who study cell systems at the molecular level a valuable tool for monitoring the health of a single cell." (Credit: ORNL).|
Now, let's move to the self-assembly process developed by Sandia National Laboratories and the University of New Mexico.
The self-assembly approach developed by the SNL/UNM teams allows nanocrystal arrays to be integrated into devices using standard microelectronic processing techniques, bridging huge gaps in scale.
Said IBM staff researcher Chuck Black at T. J. Watson Research Center in Yorktown Heights, NY, “One thing that’s nice is that these materials are hard materials. Often they come with an organic surfactant layer that makes it difficult to process materials, like a kind of grease. This material is embedded in oxide. It sounds like a neat thing and a new approach.” The Sandia/UNM approach scrubs the surfactants with an ozone compound.
Sandia has applied for a patent on this approach, which should aid attempts at several major universities to identify individual cancer cells before they increase in number.
||"This image shows self-assembled, well-shaped gold nanocrystal/silica arrays. (Credit: SNL).|
It's time to look at the high-speed nanotube transistors developed at the University of California, Irvine.
"Since the invention of nanotube transistors, there have been theoretical predictions that they can operate very fast," says Peter Burke, Ph.D., a professor of electrical engineering and computer science at the University of California, Irvine, and lead author of the paper. "Our work is the first to show that single-walled nanotube transistor devices can indeed function at very high speeds."
Burke and his colleagues built an electrical circuit with a carbon nanotube between two gold electrodes. When they varied the voltage, the circuit operated at a frequency of 2.6 gigahertz (GHz), which means electrical current could be switched on and off in about one billionth of a second. This is the first demonstration of a nanotube operating in the frequency range of microwaves — electromagnetic waves with faster frequencies than radio waves.
Finally, here are some short quotes about nanogold.
At the nano-level, gold acquires a new shine, a new set of properties and a host of potential new applications.
All that glitters is not gold, goes the old adage. But the shrinking frontiers of science require a qualifier: Gold itself does not always glitter.
In fact, if gold is created in small enough chunks, it turns red, blue, yellow and other colors, says Chris Kiely, who directs the new Nanocharacterization Laboratory in Lehigh's Center for Advanced Materials and Nanotechnology.
That's all for today. For more information, read the individual news releases.
Sources: Sandia National Laboratories, April 26, 2004; American Chemical Society, April 27, 2004, via EurekAlert!; Lehigh University, April 27, 2004; Oak Ridge National Laboratory, April 27, 2004, via EurekAlert!