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Carbon nanotubes-cylinders so tiny that it takes 50,000 lying side by side to equal the width of a human hair-are packed with the potential to be highly accurate vehicles for administering medicines and other therapeutic agents to patients. But a dearth of data about what happens to the tubes after they discharge their medical payloads has been a major stumbling block to progress. Now, Stanford researchers, who spent months tracking the tiny tubes inside mice, have found some answers. Studies in mice already had shown that most nanomaterials tend to accumulate in organs such as the liver and spleen, which...

BriefingAs big as a bed sheet, and the carbon won't rub off.NANOCOMP TECHNOLOGIES A company in the United States has made a sheet from tiny carbon nanotubes. Nature News finds out whether bigger is better when it comes to the very small. I thought the whole point about carbon nanotubes was that they are 'nano' — really, really small. True. As the name implies, nanotubes are on the order of 10-9 metres in size: they are famed for being thinner than human hair, and are typically less than a millimetre long. But they pack a lot of punch into such...

CHICAGO (Reuters) - Transistor radios tinier than a grain of sand, made using nanotechnology, can not only tune in to the traffic report, but may end up outperforming current silicon-based electronics, U.S. researchers said on Monday. The researchers made the microscopic radios out of carbon nanotubes -- tiny strands of carbon atoms -- and say in theory they could lead to faster devices. They overcame a series of obstacles that have defeated efforts to make nano-radios, including getting amplification, by making their devices on quartz wafers. "Our goal is not to make tiny radios per se, but really to develop...

(A) The thin film transistor array on a glass substrate. Inset: A magnified transparent transistor. (B) Scanning electron microscope image of the network of SWNTs. Image credit: Eun Ju Bae, et al. The ability to create flexible, transparent electronics could lead to a host of novel applications, such as e-paper and electronic car windshields. Now, scientists have constructed a transistor made of a network of nanotubes that may serve as an essential component in a trans-flex device. Such devices require two main components: light displays and current-controlling transistors. While scientists have found that OLEDs and LCDs work well as...

Presto chango! Dumping graphene oxide particles in water (top) causes them to begin binding together spontaneously into superstrong sheets.Credit: Rod Ruoff Researchers have developed a remarkably simple way to convert ordinary graphite particles into very thin but superstrong sheets that are tougher than steel and as flexible as carbon fiber but can be made much more cheaply. The discovery could spawn entirely new types of materials for applications as diverse as protective coatings, electronic components, batteries, and fuel cells. For tensile strength and stiffness, carbon is king. So it's no surprise that scientists have been working for years to develop...

DNA-like ice 'seen' inside carbon nanotubes 14:15 12 December 2006 NewScientist.com news service Tom Simonite Spectacular ice helix structures form when water molecules are squeezed into carbon nanotubes under high pressure, in computer simulations (Images: Xiao Cheng Zeng) Nanoscale ice formations resembling the double helices of DNA will form when water molecules are frozen inside carbon nanotubes, detailed computer simulations suggest. Researchers at the University of Nebraska, US, used a supercomputer to run detailed mathematical models of the behaviour of water molecules. In their simulations, they inserted the molecules into carbon nanotubes under high pressure, before cooling them to -23°C....

(Nanowerk Spotlight) Carbon nanotubes (CNTs) have great potential applications in making ballistic-resistance materials. The remarkable properties of CNTs makes them an ideal candidate for reinforcing polymers and other materials, and could lead to applications such as bullet-proof vests as light as a T-shirt, shields, and explosion-proof blankets. For these applications, thinner, lighter, and flexible materials with superior dynamic mechanical properties are required. A new study by researchers in Australia explores the energy absorption capacity of a single-walled carbon nanotube under a ballistic impact. The result offers a useful guideline for using CNTs as a reinforcing phase of materials to make...

Carbon nanotubes are no longer the proud boast of 21st century materials scientists. It appears their discovery was unwittingly pre-empted by mediaeval Muslim sword-smiths whose tough Damascus blades taught the Crusaders the true meaning of cold steel when they fought over the Holy Land. Peter Paufler and colleagues at Dresden’s Technical University discovered carbon nanotubes in the microstructure of a 17th century Damascus sabre. Intriguingly, the nanotubes could have encapsulated iron-carbide nanowires that might give clues to the mechanical strength and sharpness of these swords. To Europeans, Damascus steel blades seemed magical. Not only could they cut a piece of...

Secret's out for Saracen sabres 15 November 2006 NewScientist.com news service DURING the middle ages, the Muslims who fought crusaders with swords of Damascus steel had an edge - a very high-tech one. Their sabres contained carbon nanotubes. From about AD 900 to AD 1750, Damascus sabres were forged from Indian steel called wootz. Peter Paufler of the Technical University of Dresden, Germany, and colleagues studied samples of a 17th-century sword under an electron microscope and found clear evidence of carbon nanotubes and even nanowires. The researchers think that the sophisticated process of forging and annealing the steel formed the...

In an attempt to increase the sensitivity of cancer biomarker detection and to decrease the need for large samples from which to detect those molecules, a multi-institutional research team has shown that a “forest” of single-walled carbon nanotubes can be used to detect lower levels of the prostate specific antigen (PSA) than is possible using the current commercial assay. Moreover, this new system requires between 5 and 15 times less sample than does the commercial system. James Rusling, Ph.D., at the University of Connecticut, led the research team that developed this new assay system. The investigators report their findings in...

Based on a new theory, MIT scientists may be able to manipulate carbon nanotubes -- one of the strongest known materials and one of the trickiest to work with -- without destroying their extraordinary electrical properties. The work is reported in the Sept. 15 issue of Physical Review Letters, the journal of the American Physical Society. Carbon nanotubes -- cylindrical carbon molecules 50,000 times thinner than a human hair -- have properties that make them potentially useful in nanotechnology, electronics, optics and reinforcing composite materials. With an internal bonding structure rivaling that of another well-known form of carbon, diamonds, carbon...

In less than 20 minutes, researchers at New Jersey Institute of Technology (NJIT) can now seed, heat and grow carbon nanotubes in 10-foot-long, hollow thin steel tubing. “The work took us three years to develop and get right, but now we can essentially anchor nanotubes to a tubular wall. No one has ever done anything like this before,” said lead researcher Somenath Mitra, PhD, professor and acting chair of NJIT’s Dep’t of Chemistry and Environmental Science. Graduate and post-doctoral students who worked on the project are Mahesh Karwa, Chutarat Saridara and Roman Brukh. The ground-breaking method will lead to improvements...

Working with a material 10 times lighter than steel—but 250 times stronger—would be a dream come true for any engineer. If this material also had amazing properties that made it highly conductive of heat and electricity, it would start to sound like something out of a science fiction novel. Yet one Florida State University research group, the Florida Advanced Center for Composite Technologies (FAC2T), is working to develop real-world applications for just such a material. Dr. Ben Wang, a professor of industrial engineering at the Florida A&M University-FSU College of Engineering, serves as director of FAC2T (www.fac2t.eng.fsu.edu), which works to...

Nanotechnology, using particles as small as 100 nanometers in size, is offering exciting new possibilities for finding and treating breast tumors, according to speakers at the 28th Annual San Antonio Breast Cancer Symposium being held this week. Two researchers from Rice University in Houston, Texas, offered enticing insights into how these minute particles can be manipulated to have different properties, and tagged with antibodies to target them specifically at cancer cells. Jennifer West, PhD, has studied the unique optical properties of nanoshells. These particles consist of a nonconducting core (for example, silicon) surrounded by a metal shell of varying thickness....

They’re but a tiny speck, existing in a variety of forms: particles, tubes, shells, even a soccerball-like shape. They also share a common prefix: “nano,” connoting their size, a billionth of a meter or roughly 25-millionth of an inch. Today, cancer researchers are exploring the potential of such nanostructures to exquisitely target cancer cells without harming surrounding tissue, and to image the formation of tumors long before they have a chance to become life-threatening. While diagnostics and approved therapies are years away, several are nearing clinical studies, while a few already are being tested in patients. A press conference on...

Physicists in the US have generated extra-bright beams of infrared light from single-walled carbon nanotubes. The new technique is more efficient than many existing methods for producing light and could have applications in optoelectronics (Science 310 1171).Phaedon Avouris of IBM Research, Jie Liu of Duke University and co-workers began by laying down nanotubes with diameters of 2-3 nanometres by chemical vapour deposition. The nanotubes spanned trenches in a silica coating on a silicon substrate. Palladium source and drain electrodes were then added to the nanotubes. Suspended nanotubes The IBM-Duke team found that when certain voltages were applied, the nanotubes...

In conventional CRT TVs, an electron gun fires electrons at a phosphor-coated glass divided into pinpoints to create images. The electrons, however, need to disperse in a large vacuum, which is why TV tubes are so large and bulky. In so-called field emission display (FED) TVs, electrons get filtered into an array of thousands of tips only a few nanometers wide, which then deliver electrons to illuminate the screen. As a result, these TVs can be thin, like LCDs or plasmas. Another advantage comes in cost. The tips, whether nanotubes or diamonds or some other material, in a FED...

Carbon nanotubes are like minute bits of string, and untold trillions of these invisible strings must be assembled to make useful macroscopic articles that can exploit the phenomenal mechanical and electronic properties of the individual nanotubes. In the Aug. 19 issue of the prestigious journal Science, scientists from the NanoTech Institute at UTD and a collaborator, Dr. Ken Atkinson from Commonwealth Scientific and Industrial Research Organization (CSIRO), a national laboratory in Australia, report such assembly of nanotubes into sheets at commercially useable rates. Starting from chemically grown, self-assembled structures in which nanotubes are aligned like trees in a forest, the...

Traditional attempts to destroy cancerous tumors involve treatments such as chemotherapy that kill healthy cells right along with mutated ones, often leaving patients weak, nauseous, hairless and vulnerable to infection. But now biologists and engineers at the Massachusetts Institute of Technology have engineered a dual-chamber molecular bomb designed to infiltrate a tumor, shut down its blood vessels — thereby sealing off the exits — and detonate a dose of cancer-killing toxins. The drug-delivering nanocell, reported recently in the journal Nature, could help usher in more effective cancer therapies that pinpoint and obliterate disease without harming normal, healthy cells. "By having...

Scientists have shown for the first time that carbon nanotubes make an ideal scaffold for the growth of bone tissue. The new technique could change the way doctors treat broken bones, allowing them to simply inject a solution of nanotubes into a fracture to promote healing. The report appears in the June 14 issue of the American Chemical Society’s journal Chemistry of Materials. ACS is the world’s largest scientific society. The success of a bone graft depends on the ability of the scaffold to assist the natural healing process. Artificial bone scaffolds have been made from a wide variety of...