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Researchers at MIT and Harvard Medical School have built targeted nanoparticles that can cling to artery walls and slowly release medicine, an advance that potentially provides an alternative to drug-releasing stents in some patients with cardiovascular disease. The particles, dubbed “nanoburrs” because they are coated with tiny protein fragments that allow them to stick to target proteins, can be designed to release their drug payload over several days. The nanoburrs are targeted to a specific structure, known as the basement membrane, which lines the arterial walls and is only exposed when those walls are damaged. Therefore, the nanoburrs could be used to deliver drugs to treat atherosclerosis and other inflammatory cardiovascular diseases. They are one of the first such targeted particles that can precisely home in on damaged vascular tissue, says Omid Farokhzad, associate professor at Harvard Medical School. Farokhzad and MIT Institute Professor Robert Langer have previously developed nanoparticles that seek out and destroy tumorsThe researchers hope the particles could become a complementary approach that can be used with vascular stents, which are the standard of care for most cases of clogged and damaged arteries, or in lieu of stents in areas not well suited to them, such as near a fork in the artery.

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Stanford University scientists are harnessing nanotechnology to quickly produce ultra-lightweight, bendable batteries and supercapacitors in the form of everyday paper. Simply coating a sheet of paper with ink made of carbon nanotubes and silver nanowires makes a highly conductive storage device, said Yi Cui, assistant professor of materials science and engineering. "Society really needs a low-cost, high-performance energy storage device, such as batteries and simple supercapacitors," he said. Like batteries, capacitors hold an electric charge, but for a shorter period of time. However, capacitors can store and discharge electricity much more rapidly than a battery.
httpvh://www.youtube.com/watch?v=QPTcQJPbGHw
Above: Post doctoral students in the lab of Prof. Yi Cui, Materials Science and Engineering, light up a diode from a battery made from treated paper, similar to what you would find in a copy machine. The paper batteries are treated with a nanotube ink, baked and folded into electrical generating sources like the one wrapped in foil seen here. (Video Credit: Stanford University)

"These nanomaterials are special," Cui said. "They're a one-dimensional structure with very small diameters." The small diameter helps the nanomaterial ink stick strongly to the fibrous paper, making the battery and supercapacitor very durable. The paper supercapacitor may last through 40,000 charge-discharge cycles – at least an order of magnitude more than lithium batteries. The nanomaterials also make ideal conductors because they move electricity along much more efficiently than ordinary conductors, Cui said. Cui had previously created nanomaterial energy storage devices using plastics. His new research shows that a paper battery is more durable because the ink adheres more strongly to paper (answering the question, "Paper or plastic?").
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This illustration shows the tip of a scanning tunneling microscope approaching an undulating sheet of perfect graphene. The exotic substance is 10 times stronger than steel and conducts electricity better than any known material at room temperature. Both physicists and nanoscientists are studying graphene and exploring its potential applications. (Image Source: Vanderbilt Univeristy; Image Credit: Calvin Davidson, British Carbon Group)

First, it was the soccer-ball-shaped molecules dubbed buckyballs. Then it was the cylindrically shaped nanotubes. Now there is graphene: a remarkably flat molecule made of carbon atoms arranged in hexagonal rings much like molecular chicken wire.  It is 10 times stronger than steel and conducts electricity better than any other known material at room temperature. These and graphene’s other exotic properties have attracted the interest of physicists, who want to study them, and nanotechnologists, who want to exploit them to make novel electrical and mechanical devices. Although graphene is the first truly two-dimensional crystalline material that has been discovered, over the years scientists have put considerable thought into how two-dimensional gases and solids should behave. They have also succeeded in creating a close approximation to a two-dimensional electron gas by bonding two slightly different semiconductors together. Electrons are confined to the interface between the two and their motions are restrained to two dimensions. When such a system is cooled down to less than one degree above absolute zero and a strong magnetic field is applied, then the fractional quantum Hall effect appears. Since scientists figured out how to make graphene five years ago, they have been trying to get it to exhibit this effect with only marginal success. The best way to understand it is to think of the electrons in graphene as a forming a (very thin) sea of charge. When the magnetic field is applied, it generates whirlpools in the electron fluid. Because electrons carry a negative charge, these vortices have a positive charge.
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As depicted in this illustration, tiny particles of a gold-aluminum alloy were alternately heated and cooled inside a vacuum chamber, and then silicon and germanium gases were alternately introduced. As the gold-aluminum bead absorbed the gases, it became "supersaturated" with silicon and germanium, causing them to precipitate and form wires. (Image Source: Purdue University, Birck Nanotechnology Center/Seyet LLC)

A new generation of ultrasmall transistors and more powerful computer chips using tiny structures called semiconducting nanowires is closer to reality after a key discovery by researchers at IBM, Purdue University and the University of California at Los Angeles.  The researchers have learned how to create nanowires with layers of different materials that are sharply defined at the atomic level, which is a critical requirement for making efficient transistors out of the structures. "Having sharply defined layers of materials enables you to improve and control the flow of electrons and to switch this flow on and off," said Eric Stach, an associate professor of materials engineering at Purdue. Electronic devices are often made of "heterostructures," meaning they contain sharply defined layers of different semiconducting materials, such as silicon and germanium. Until now, however, researchers have been unable to produce nanowires with sharply defined silicon and germanium layers. Instead, this transition from one layer to the next has been too gradual for the devices to perform optimally as transistors. The new findings point to a method for creating nanowire transistors. Whereas conventional transistors are made on flat, horizontal pieces of silicon, the silicon nanowires are "grown" vertically. Because of this vertical structure, they have a smaller footprint, which could make it possible to fit more transistors on an integrated circuit, or chip, Stach said. New technologies will be needed for industry to maintain Moore's law, an unofficial rule stating that the number of transistors on a computer chip doubles about every 18 months, resulting in rapid progress in computers and telecommunications. Doubling the number of devices that can fit on a computer chip translates into a similar increase in performance. However, it is becoming increasingly difficult to continue shrinking electronic devices made of conventional silicon-based semiconductors . 
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Scanning electron micrograph of two thin, flat rings of silicon nitride, each 190 nanometers thick and mounted a millionth of a meter apart. Under the right conditions optical forces between the two rings are enough to bend the thin spokes and pull the rings toward one another, changing their resonances enough to act as an optical switch. Image Credit: Cornell Nanophotonics Group

With a bit of leverage, researchers have used a very tiny beam of light with as little as 1 milliwatt of power to move a silicon structure up to 12 nanometers. That’s enough to completely switch the optical properties of the structure from opaque to transparent, they report.

The technology could have applications in the design of nanoscale devices with moving parts—known as micro-electromechanical systems (MEMS)—and micro-optomechanical systems (MOMS), which combine moving parts with photonic circuits, says Michal Lipson, associate professor of electrical and computer engineering at Cornell University. Light can be thought of as a stream of particles that can exert a force on whatever they strike. The sun doesn’t knock you off your feet because the force is very small, but at the nanoscale it can be significant. “The challenge is that large optical forces are required to change the geometry of photonic structures,” Lipson explained.
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Mouse tumor cells stain red, showing penetration of anti-cancer drug after 24 hours. Image Credit: Pratt School of Engineering, Duke University

Going smaller could bring better results, especially when it comes to cancer-fighting drugs. Duke University bioengineers have developed a simple and inexpensive method for loading cancer drug payloads into nano-scale delivery vehicles and demonstrated in animal models that this new nanoformulation can eliminate tumors after a single treatment. After delivering the drug to the tumor, the delivery vehicle breaks down into harmless byproducts, markedly decreasing the toxicity for the recipient. Nano-delivery systems have become increasingly attractive to researchers because of their ability to efficiently get into tumors. Since blood vessels supplying tumors are more porous, or leaky, than normal vessels, the nanoformulation can more easily enter and accumulate within tumor cells. This means that higher doses of the drug can be delivered, increasing its cancer-killing abilities while decreasing the side effects associated with systematic chemotherapy.
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For the first time, researchers can use infrared spectroscopy to determine what type of bonds protein molecules contain and to identify materials. The new technique has been sought to overcome several limitations of the current, standard technique.Image Credit: Hatice Altug, Electrical Engineering Department, Boston University

An interdisciplinary team of researchers has created a new, ultra-sensitive technique to analyze life-sustaining protein molecules. The technique may profoundly change the methodology of biomolecular studies and chart a new path to effective diagnostics and early treatment of complex diseases. Researchers from Boston University and Tufts University near Boston recently demonstrated an infrared spectroscopy technique that can directly identify the "vibrational fingerprints" of extremely small quantities of proteins, the machinery involved in maintaining living organisms. The new technique exploits nanotechnology to overcome several limitations of current, conventional techniques used to study biomolecules. Previous bio-molecular study methods commonly use fluorescence spectroscopy, where biomolecules are labeled with very bright fluorescence tags to track how efficiently they interact with each other. Understanding interactions is important for medical drug research. Molecules consist of atoms bonded to each other with springs. Depending on the mass of atoms, how stiff these springs are, or how the atoms' springs are arranged, the molecules rotate and vibrate at specific frequencies similar to a guitar string that vibrates at specific frequencies depending on the string length. These resonant frequencies are molecule specific and they mostly occur in the infrared frequency range of the electromagnetic spectrum. The sensitivity of infrared spectroscopy previously had been too low to detect these vibrations, particularly from small quantities of samples.
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  Brain implants that can more clearly record signals from surrounding neurons in rats have been created at the University of Michigan. The findings could eventually lead to more effective treatment of neurological disorders such as Parkinson's disease and paralysis. Neural electrodes must work for time periods ranging from hours to years. When the electrodes are implanted, the brain first reacts to the acute injury with an inflammatory response. Then the brain settles into a wound-healing, or chronic, response. It's during this secondary response that brain tissue starts to encapsulate the electrode, cutting it off from communication with surrounding neurons. The new brain implants developed at U-M are coated with nanotubes made of poly(3,4-ethylenedioxythiophene) (PEDOT), a biocompatible and electrically conductive polymer that has been shown to record neural signals better than conventional metal electrodes. U-M researchers found that PEDOT nanotubes enhanced high-quality unit activity (signal-to-noise ratio >4) about 30 percent more than the uncoated sites. They also found that based on in vivo impedance data, PEDOT nanotubes might be used as a novel method for biosensing to indicate the transition between acute and chronic responses in brain tissue. Find out more... 

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3D Electron tomography image of a polymer-metal oxide solar cell. The 3D nanoscopic morphology shows the interpenetrating metal oxide network in (yellow) inside a polymer matrix (black).Image Source: Eindhoven University of Technology

Researchers from the Eindhoven University of Technology (TU/e) have made the first high-resolution 3D images of the inside of a polymer solar cell. This gives them important new insights in the nanoscale structure of a polymer solar cell and the effect on its performance. The research was a joint effort of TU/e-researchers and colleagues at the University of Ulm, Germany. The investigations shed new light on the operational principles of polymer solar cells. This is expected to be very important for the development of better polymer solar cells. Polymer solar cells do not have the high efficiencies of their silicon counterparts yet. Polymer cells, however, can be printed in roll-to-roll processes, at very high speeds, which makes the technology potentially very cost-effective. Added to that, polymer cells are flexible and lightweight, and therefore suitable to be used on vehicles or clothing or to be incorporated in the design of objects. In these hybrid solar cells, a mixture of two different materials, a polymer and a metal oxide are used to create charges at their interface when the mixture is illuminated by the sun.
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POSTECH's research team, led by chemistry professor Kim Kwang-soo, said it has successfully synthesized lenses that are hundreds of times thinner than a single hair. The team discovered a new physics phenomenon. When the size of a lens shrinks to the level of the wavelength of light, it shows the ultra-resolution that thinner things than the half wavelength of light could be distinguished. The half-wavelength of light is theoretically limiting value of diffraction in traditional geometrical optics. Kim's team found that the organic matter Calix Hydro Quinon can shape a nanometer-thin cross-sectioned convex lens. The team found an ultra-refraction for the first time in which a light-wavelength-thin lens makes the light draw a curve through diffraction and interference and makes the nano-lens have a very short focal distance. The team proved the intriguing optical phenomenon of the nano-lens through the precise simulation of electromagnetic waves and established a new physical phenomenon theory. The optical features of a nanometer-thin lens can be used to analyze structures of nano and micro-bio substances, to improve technologies for the development of nano components, and to integrate light that is impossible to observe with traditional optical microscopes. Nanometerthin lenses can be also used for the development of next-generation nano-optical memories and detection components. The success of the research resulted from cooperation between academics in chemistry, physics, and mechanical and electronic engineering.
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