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Project to help bring widespread use of micro-robotics

Nanotech-Now - August 5, 2016 - 7:45am
Micro-robotic manipulators with the ability to move in increments far smaller than the width of a human hair might be enlisted for a range of applications in research, manufacturing, medicine and home...

Park Systems Launches Park NX20 300mm Research Atomic Force Microscope with Full 300 mm Semiconductor Wafer Scan - Vastly Improving Productivity

Nanotech-Now - August 5, 2016 - 7:45am
Park Systems, world leading manufacturer of Atomic Force Microscopes (AFM) today announced Park NX20 300mm, the first and only research AFM on the market capable of scanning the entire sample area...

Wireless, wearable toxic-gas detector

InterNano Industry News - August 5, 2016 - 3:45am
MIT researchers have developed low-cost chemical sensors, made from chemically altered carbon nanotubes, that enable smartphones or other wireless devices to detect trace amounts of toxic gases. Using the sensors, the researchers hope to design lightweight, inexpensive radio-frequency identification (RFID) badges to be used for personal safety and security. Such badges could be worn by soldiers on the battlefield to rapidly detect the presence of chemical weapons — such as nerve gas or choking agents — and by people who work around hazardous chemicals prone to leakage.   “Soldiers have all this extra equipment that ends up weighing way too much and they can’t sustain it,” says Timothy Swager, the John D. MacArthur Professor of Chemistry and lead author on a paper describing the sensors that was published in the Journal of the American Chemical Society. “We have something that would weigh less than a credit card. And [soldiers] already have wireless technologies with them, so it’s something that can be readily integrated into a soldier’s uniform that can give them a protective capacity.” The sensor is a circuit loaded with carbon nanotubes, which are normally highly conductive but have been wrapped in an insulating material that keeps them in a highly resistive state. When exposed to certain toxic gases, the insulating material breaks apart, and the nanotubes become significantly more conductive. This sends a signal that’s readable by a smartphone with near-field communication (NFC) technology, which allows devices to transmit data over short distances. The sensors are sensitive enough to detect less than 10 parts per million of target toxic gases in about five seconds. “We are matching what you could do with benchtop laboratory equipment, such as gas chromatographs and spectrometers, that is far more expensive and requires skilled operators to use,” Swager says. Moreover, the sensors each cost about a nickel to make; roughly 4 million can be made from about 1 gram of the carbon nanotube materials. “You really can’t make anything cheaper,” Swager says. “That’s a way of getting distributed sensing into many people’s hands.” The paper’s other co-authors are from Swager’s lab: Shinsuke Ishihara, a postdoc who is also a member of the International Center for Materials Nanoarchitectonics at the National Institute for Materials Science, in Japan; and PhD students Joseph Azzarelli and Markrete Krikorian.  Wrapping nanotubes In recent years, Swager’s lab has developed other inexpensive, wireless sensors, called chemiresistors, that have detected spoiled meat and the ripeness of fruit, among other things. All are designed similarly, with carbon nanotubes that are chemically modified, so their ability to carry an electric current changes when exposed to a target chemical. This time, the researchers designed sensors highly sensitive to “electrophilic,” or electron-loving, chemical substances, which are often toxic and used for chemical weapons. To do so, they created a new type of metallo-supramolecular polymer, a material made of metals binding to polymer chains. The polymer acts as an insulation, wrapping around each of the sensor’s tens of thousands of single-walled carbon nanotubes, separating them and keeping them highly resistant to electricity. But electrophilic substances trigger the polymer to disassemble, allowing the carbon nanotubes to once again come together, which leads to an increase in conductivity. In their study, the researchers drop-cast the nanotube/polymer material onto gold electrodes, and exposed the electrodes to diethyl chlorophosphate, a skin irritant and reactive simulant of nerve gas. Using a device that measures electric current, they observed a 2,000 percent increase in electrical conductivity after five seconds of exposure. Similar conductivity increases were observed for trace amounts of numerous other electrophilic substances, such as thionyl chloride (SOCl2), a reactive simulant in choking agents. Conductivity was significantly lower in response to common volatile organic compounds, and exposure to most nontarget chemicals actually increased resistivity. Creating the polymer was a delicate balancing act but critical to the design, Swager says. As a polymer, the material needs to hold the carbon nanotubes apart. But as it disassembles, its individual monomers need to interact more weakly, letting the nanotubes regroup. “We hit this sweet spot where it only works when it’s all hooked together,” Swager says. Resistance is readable To build their wireless system, the researchers created an NFC tag that turns on when its electrical resistance dips below a certain threshold. Smartphones send out short pulses of electromagnetic fields that resonate with an NFC tag at radio frequency, inducing an electric current, which relays information to the phone. But smartphones can’t resonate with tags that have a resistance higher than 1 ohm. The researchers applied their nanotube/polymer material to the NFC tag’s antenna. When exposed to 10 parts per million of SOCl2 for five seconds, the material’s resistance dropped to the point that the smartphone could ping the tag. Basically, it’s an “on/off indicator” to determine if toxic gas is present, Swager says. According to the researchers, such a wireless system could be used to detect leaks in Li-SOCl2 (lithium thionyl chloride) batteries, which are used in medical instruments, fire alarms, and military systems. Alexander Star, a professor of chemistry and bioengineering and clinical and translational science at the University of Pittsburgh, says the researchers’ design for a wireless sensor (or dosimeter) for electrophilic substances could improve soldier safety. “The authors were able to synthesize a [carbon nanotube] composite sensitive to … a class of chemicals of high interest for sensing,” Star says. “This type of device architecture is important for real-life application, due to the fact that a chemical weapon dosimeter worn by military and security personnel requires rapid reading.” The next step, Swager says, is to test the sensors on live chemical agents, outside of the lab, which are more dispersed and harder to detect, especially at trace levels. In the future, there’s also hope for developing a mobile app that could make more sophisticated measurements of the signal strength of an NFC tag: Differences in the signal will mean higher or lower concentrations of a toxic gas. “But creating new cell phone apps is a little beyond us right now,” Swager says. “We’re chemists.” The work was supported by the National Science Foundation and the Japan Society for the Promotion of Science.
Categories: Nanotechnology News

“Ostwald ripening” improves solar cells

Nanotechweb - August 5, 2016 - 2:58am
A new and easy way to turn low-quality perovskite films into high-quality ones.

Materials Characterization Workshop

InterNano - Upcoming Events - August 4, 2016 - 11:19am
Workshop/TrainingTuesday, August 23, 2016 to Wednesday, August 24, 2016University of Delaware - Newark, DE http://sites.udel.edu/materials-characterization/ Today’s materials – from biomaterials to thin films and materials used in renewable energy production – range in size from macro- to nanoscale and require a variety of characterization techniques throughout their design and fabrication. With this in mind, the University of Delaware has once again assembled an interdisciplinary roster of renowned experts in nanofabrication and materials characterization. Featured Speakers: D. Bruce Chase, University of Delaware David G. Cory, University of Waterloo Alain Diebold, State University of New York Polytechnic Institute Mrignayani Kotecha, University of Illinois at Chicago Theodore R. Krause, Argonne National Laboratory J. Alexander Liddle, National Institute of Standards & Technology Jennifer Mass, University of Delaware and Winterthur Museum Susanna M. Thon, Johns Hopkins University

Nanoparticles carrying rapamycin help lower immune response to biologic drugs

Nanotechweb - August 4, 2016 - 1:16am
Novel immunotherapy could help prevent the formation of antidrug antibodies.

All phase-change neuromorphic device recognises correlations

Nanotechweb - August 3, 2016 - 7:52am
(with movie)Incorporating a level-tuning mechanism in a neuromorphic device that has both phase-change synapses and neurons, advances the ability to distinguish patterns and correlations.

A new leaf: Scientists turn carbon dioxide back into fuel

Nanotech-Now - August 3, 2016 - 7:45am
As scientists and policymakers around the world try to combat the increasing rate of climate change, they have focused on the chief culprit: carbon dioxide.

Swapping substrates improves edges of graphene nanoribbons: Using inert boron nitride instead of silica creates precise zigzag edges in monolayer graphene

Nanotech-Now - August 3, 2016 - 7:45am
It is now feasible to make a prized material for spintronic devices and semiconductors -- monolayer graphene nanoribbons with zigzag edges.

Synthetic vaccine particles immune tolerance mechanism published in Nature Nanotechnology: Antigen-specific targeting of the immune system offers new treatment approach to improve efficacy and safety profile of biologic drugs

Nanotech-Now - August 3, 2016 - 7:45am
Selecta Biosciences, Inc. (NASDAQ: SELB), a clinical-stage biopharmaceutical company developing targeted antigen-specific immune therapies for rare and serious diseases, announced today that Nature Na...

IBM Lab-on-a-Chip Breakthrough Aims to Help Physicians Detect Cancer and Diseases at the Nanoscale: IBM scientists will collaborate with the Icahn School of Medicine at Mt. Sinai to test on prostate cancer

Nanotech-Now - August 3, 2016 - 7:45am
IBM (NYSE: IBM) scientists have developed a new lab-on-a-chip technology that can, for the first time, separate biological particles at the nanoscale and could enable physicians to detect diseases suc...

STMicroelectronics Earns MEMS Manufacturer of the Year Award

Nanotech-Now - August 3, 2016 - 7:45am
STMicroelectronics (NYSE: STM), a global semiconductor leader serving customers across the spectrum of electronics applications, has been named the MEMS Manufacturer of the Year at the MEMS World Summ...

PPPL applies quantum theory and Einstein's special relativity to plasma physics issues

Nanotech-Now - August 3, 2016 - 7:45am
Among the intriguing issues in plasma physics are those surrounding X-ray pulsars -- collapsed stars that orbit around a cosmic companion and beam light at regular intervals, like lighthouses in the s...

New material could advance superconductivity

Nanotech-Now - August 3, 2016 - 7:45am
Scientists have looked for different ways to force hydrogen into a metallic state for decades. A metallic state of hydrogen is a holy grail for materials science because it could be used for supercond...

Scientists find a way of acquiring graphene-like films from salts to boost nanoelectronics: Physicists use supercomputers to find a way of making 'imitation graphene' from salt

Nanotech-Now - August 3, 2016 - 7:45am
Researchers from Moscow Institute of Physics and Technology (MIPT), Skolkovo Institute of Science and Technology (Skoltech), the Technological Institute for Superhard and Novel Carbon Materials (TISNC...

Vortex laser offers hope for Moore's Law: The optics advancement may solve an approaching data bottleneck by helping to boost computing power and information transfer rates tenfold

Nanotech-Now - August 3, 2016 - 7:45am
Like a whirlpool, a new light-based communication tool carries data in a swift, circular motion. Described in a study published today (July 28, 2016) by the journal Science, the optics advancement...

New method for making green LEDs enhances their efficiency and brightness

Nanotech-Now - August 3, 2016 - 7:45am
Researchers at the University of Illinois at Urbana Champaign have developed a new method for making brighter and more efficient green light-emitting diodes (LEDs). Using an industry-standard semicond...