Never before has the nano-scale world of viruses and proteins been so visible. A team led by scientists at IBM Research has developed a new imaging technique based on the same principles used in magnetic resonance imaging, or MRI, which is routinely used in hospitals. But the new process has 100 million times better resolution than a conventional MRI, allowing researchers to construct 3-D images of individual tobacco mosaic viruses, which are only 18 nanometers in diameter. “This technology stands to revolutionize the way we look at viruses, bacteria, proteins, and other biological elements,” said IBM [researcher] Mark Dean…. This advancement was enabled by a technique called magnetic resonance force microscopy (MRFM), which relies on detecting ultrasmall magnetic forces [CNN].
The MRFM process hasn’t captured images of the smallest objects ever: Techniques like atomic force and scanning tunneling microscopes have provided images of individual atoms. (An atom is about one-tenth of a nanometer in diameter). But these techniques are more destructive of biological samples because they send a stream of electrons at the target in order to get an image. And these microscopes cannot peer beneath the surface of the Lilliputian structures [The New York Times]. Researchers say the new 3-D technique will be enormously valuable for the study of protein structures.
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By harnessing a quantum mechanic force of repulsion researchers have caused nanoparticles to repel each other, and in their next experiment they plan to levitate a tiny gold nanosphere. The quantum force is part of the Casimir effect, first predicted in 1948 by the Dutch physicist Hendrik Casimir, which describes both the attraction and repulsion that occur between two tiny objects held close together in a vacuum. While the attractive force has previously been demonstrated, the new experiment marks the first time the repulsive force has been seen in a lab.
But the experiment wasn’t just a neat physics trick; the researchers say the repulsive force may one day be used in nanoscale devices. Lead author Jeremy Munday says the research may lend itself to producing ultrasensitive detectors and almost friction-free devices by separating their components via Casimir repulsion. “Where you would normally have friction,” he says, “you can start to greatly reduce that by having a repulsive interaction that doesn’t let the surfaces come into contact” [Scientific American].
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Federal research on the emerging field of nanotechnology has failed to adequately address health, safety, and environmental concerns, according to a critical new report from the National Research Council. With more than 600 products that use nanotech materials already on the market, the lag in research creates a risk to consumers, and could also fuel a “nanophobia” in which people assume that every product that uses the new technology is harmful. David Rejeski, director of the Project on Emerging Nanotechnologies … said the report echoed calls by industry and congressional leaders for a revamped research plan for nanotechnology. “The administration’s delay has hurt investor and consumer confidence,” Rejeski said in a statement. “It has gambled with public health and safety” [Reuters].
Nanomaterials are engineered on the scale of a billionth of a meter, perhaps 1/10,000 the width of a human hair. They are turning up in a range of items including consumer products like toothpaste and tennis rackets and industrial products like degreasers or adhesives [The New York Times]. Engineered nanoparticles can also be found in sunscreens, cosmetics, and the fabric used in “nano-pants” that resist stains.
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IBM has won a $4.9 million government grant from DARPA to begin the first phase of research on “cognitive computing”– essentially building computers that work like living brains. The new brain-like computers will aim to process vast amounts of data to solve problems without relying on specific programmed algorithms. Mark Dean, Vice President of IBM said, “The challenge is that computers today are very good at computing, but what we really need is a more efficient way of sifting through information” [International Herald Tribune].
The inside of computers already have the look of neural networks, a static road map of electronic circuits. But the brain actually works by constantly creating, breaking, and tweaking the synaptic connections between neurons. Although today’s computers may excel at complex challenges with clear rules, like chess, they fail at simple tasks that require strategy, sensation, perception, and learning, like finding misplaced keys. IBM will partner with five universities to develop new nano-scale circuitry that has the ability to shift depending on the signals that pass through them. Free from the constraints of explicitly programmed function, computers could gather together disparate information, weigh it based on experience, form memory independently and arguably begin to solve problems in a way that has so far been the preserve of what we call “thinking” [BBC].
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Next-generation loudspeakers could be as thin as paper, as clear as glass, and as stretchable as rubber. Chinese researchers have discovered that sheets of carbon nanotubes can amplify sound as loud as conventional speakers can. These nanotube speakers could eventually be used to add audio capabilities to windows, video screens, and clothing. “It is so wonderfully simple, that it brings up a strong wave of ‘Duh, why didn’t I think of that!’,” says physical chemist Howard Schmidt at Rice University [Nature News].
The researchers made the speaker by aligning carbon nanotubes, each about 10 nanometers in diameters, into thin flexible sheets. When they applied an electric current with an audio frequency to the sheets, the sheets broadcast the sounds loud and clear. The researcher describe their device in Nano Letters. The physics behind the nanotube speakers is different from that of conventional speakers. Unlike standard loudspeakers that generate sound by vibrations in the surrounding air molecules, the nanotube speaker doesn’t emit vibrations. The team used a laser vibrometer to detect vibrations in the sheet, but found nothing [Physorg.com].
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A thin nanotech paper that’s being developed in a Florida lab could revolutionize everything from aviation to laptop computers, researchers say. The super-strong “buckypaper” could be layered like papier-mâché to build lighter airplanes and cars, or it could be exposed to an electric charge and used to illuminate computer and television screens–and those are just the most obvious applications, researchers say.
Buckypaper is 10 times lighter but potentially 500 times stronger than steel when sheets of it are stacked and pressed together to form a composite. Unlike conventional composite materials, though, it conducts electricity like copper or silicon and disperses heat like steel or brass. “All those things are what a lot of people in nanotechnology have been working toward as sort of Holy Grails,” said [nanotech expert] Wade Adams [AP].
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Researchers have invented a new tool in the fight against antibiotic-resistant “superbugs” that are becoming a growing health threat worldwide: a nanoscale device that shows instantly whether new drugs can kill the bacteria. The device uses tiny springboards coated in bacteria proteins, which are then exposed to an antibiotic; if the drug effectively binds to the proteins, the springboard bends.
[D]rug resistant superbugs are becoming more common and increasingly causing problems outside of hospitals. So [lead researcher Rachel] McKendry and colleagues want to find speedier ways to screen new potential antibiotics. They say their new nanoscale device can help, revealing in minutes whether an antibiotic is potent enough to kill bacteria [New Scientist]. Typically, researchers test new antibiotics by growing a bacterial culture and then applying the antibiotics, but it can take days for the cultures to grow.
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Would-be superheros have a cause for celebration, as the ability to walk up walls just got a little closer. Researchers have developed a nanotech superglue modeled on the minute structures on gecko feet that allow the lizards to scamper up sheer surfaces. They say the new glue is three times stronger than previous gecko-inspired glues, and ten times stickier than the lizards themselves.
The gecko owes its gravity-defying capacity to tiny structures that make use of the atomic-scale attractive van der Waals force. Look close enough at a gecko foot and you will see an ordered, forest-like structure — roughly half a million fine hairs that each sprout into hundreds of even thinner, spatula-shaped tips. When these tips come into close contact with a surface they induce strong van der Waals forces that keep the foot anchored — that is, until the gecko decides to peel it off [Physics World].
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Researchers have used nets of carbon nanotubes to print electronic circuits on to thin, flexible sheets of plastic, in yet another example of nanotechnology‘s expanding possibilities. The work is a major step towards the development of ‘plastic electronics’, where circuits on light, flexible surfaces could provide a range of products from paper-thin displays to intelligent food packaging and smart clothing [Chemistry World].
Everyone from entrepreneurs to the military is dreaming up applications for flexible electronics: They could be used to make a single-page electronic newspaper, for example, or could be formed into an electronic “skin” that covers an entire airplane, and checks the plane’s surface for cracks. Since the typical silicon-based circuits are too rigid to use in such devices, researchers have been trying out new materials. The other major contender is semiconductors that use organic molecules, but those have been shown to have poor performance and reliability.
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Sometimes good things come in small packages. Researchers say they’ve developed a nanoparticle that can deliver cancer-fighting drugs to a tumor’s blood vessels with laser-like precision, and that studies in mice show that this system could stop tumors from metastasizing, or spreading through the body.
Researchers say that packaging a toxic chemotherapy drug in nanoparticles for specific delivery to cancer cells, rather than a larger, wide-acting dose, could make for safer and more potent cancer treatments. “There are many drugs that companies have made that have fallen by the wayside or been shelved due to toxicity,” says [study author] David Cheresh [New Scientist].
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A mesh made of tiny metal nanowires could clean up oil spills in the ocean, according to a new report [Nature Nanotechnology, subscription required]. The “nanosponge,” which looks like a thin piece of brown paper, can sit on top of water without ever getting wet, while absorbing 20 times its weight in oil.
The MIT nanotech researchers haven’t tested their invention outside the lab yet, but say the nanosponge could be more effective than materials that are currently used to sop up oil, which often absorb water as well as the targeted oil, and which can’t be reused.
The nanowires, which are each 20 nanometers in diameter, are made of potassium manganese oxide and clump together naturally in dense tangles. The researchers then coated the material with a water-repelling silicone layer.
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