Friday, December 31, 2010

This week in nanotechnology - December 31, 2010

Researchers from the Quantum Photonics Group at DTU Fotonik in collaboration with the Niels Bohr Institute, University of Copenhagen surprise the scientific world with the discovery that light emission from solid-state photon emitters, the so-called quantum dots, is fundamentally different than hitherto believed. The new insight may find important applications as a way to improve efficiency of quantum information devices.

Your genome in minutes: New technology could slash sequencing time. Scientists from Imperial College London are developing technology that could ultimately sequence a person's genome in mere minutes, at a fraction of the cost of current commercial techniques. In the new study, the researchers demonstrated that it is possible to propel a DNA strand at high speed through a tiny 50 nanometre (nm) hole - or nanopore - cut in a silicon chip, using an electrical charge. As the strand emerges from the back of the chip, its coding sequence (bases A, C, T or G) is read by a 'tunnelling electrode junction'.

An interdisciplinary team of researchers at UC Santa Barbara has produced a groundbreaking study of how nanoparticles are able to biomagnify in a simple microbial food chain.

Researchers in Japan have succeeded in controlling the few-particle quantum state of a semiconductor quantum dot, and changing its correlation energies. This research achievement will make it possible to develop semiconductor non-linear devices which enable stable drive with low power consumption.

Just as walkie-talkies transmit and receive radio waves, carbon nanotubes can transmit and receive light at the nanoscale, Cornell researchers have discovered. The researchers used the Rayleigh scattering of light -- the same phenomenon that creates the blue sky -- from carbon nanotubes grown in the lab. They found that while the propagation of light scattering is mostly classical and macroscopic, the color and intensity of the scattered radiation is determined by intrinsic quantum properties.

An international team of researchers has announced a breakthrough that gives a new spin to semiconductor nanoelectronics and the world of information technology. The team has developed an electrically controllable device whose functionality is based on an electron's spin. Their results are the culmination of a 20-year scientific quest involving many international researchers and groups. The team is the first to combine the spin-helix state and anomalous Hall effect to create a realistic spin-field-effect transistor (FET) operable at high temperatures, complete with an AND-gate logic device.

Researchers in Japan Researchers fabricate first single crystal diamond nanoelectromechanical switch. The NEMS switch has the advantages of low-leakage current, low-power consumption and sharp on/off ratio in comparison with the conventional semiconductor devices.

And finally, some Friday fun - researchers etch the periodic table onto a single hair:

Friday, December 17, 2010

This week in nanotechnology - December 17, 2010

University of Utah physicists stored information for 112 seconds in what may become the world's tiniest computer memory: magnetic "spins" in the centers or nuclei of atoms. Then the physicists retrieved and read the data electronically – a big step toward using the new kind of memory for both faster conventional and superfast "quantum" computers.

Researchers open the door to biological computers. Genetically modified cells can be made to communicate with each other as if they were electronic circuits. Using yeast cells, a group of researchers at the University of Gothenburg, Sweden, has taken a groundbreaking step towards being able to build complex systems in the future where the body's own cells help to keep us healthy.
Genetically modified cells can be made to communicate with each other as if they were electronic circuits
Genetically modified cells can be made to communicate with each other as if they were electronic circuits.

You can touch a functioning light bulb and know right away that it's hot. Ouch! But you can't touch a single molecule and get the same feedback. Rice University researchers say they have the next best thing -- a way to determine the temperature of a molecule or flowing electrons by using Raman spectroscopy combined with an optical antenna.

Artificial fluidic nanochannels that mimic the capabilities of transmembrane proteins are highly prized for a number of advanced technologies. However, it has been difficult to make individual artificial channels of this size – until now. Researchers with the Berkeley Lab have been able to fabricate nanochannels that are only two nanometers in size, using standard semiconductor manufacturing processes.

Engineers at Duke and Harvard universities have developed a "magnetic sponge" that after implantation into a patient can "squeeze" out drugs, cells, or other agents when passed over by a magnet. The researchers demonstrate that the new material — called a macroporous ferrogel — can be compressed as much as 70 percent by an applied magnetic field. The reversible compression quickly forces out the drugs, cells, or proteins embedded in the ferrogel.

Microchips that 'harvest' the energy they need from their own surroundings, without depending on batteries or mains electricity. That will be possible now that researchers from the University of Twente's MESA+ Institute for Nanotechnology have for the first time succeeded in manufacturing a microchip with an efficient solar cell placed on top of the microelectronics.

A nano endoscope for living cells. Researchers have now developed a multifunctional endoscope-like device, using individual carbon nanotubes for prolonged intracellular probing at the single-organelle level, without any recordable disturbance to the metabolism of the cell. These endoscopes can transport attoliter volumes of fluid, record picoampere signals from cells, and can be manipulated magnetically. Furthermore, the tip deflects with submicrometer resolution, and the attachment of gold nanoparticles allows intracellular fingerprinting using surface-enhanced Raman spectroscopy (SERS).

Friday, December 10, 2010

This week in nanotechnology - December 10, 2010

Taking a leaf from animals like dolphins and pilot whales that are known to have anti-fouling skins, researchers are using nanotechnology to create anti-bacteria plastic 'skins' with nanoimprint technology  – synthetic, chemical-free, anti-bacterial surfaces. The surfaces can reduce infections caused by pathogens such as S. aureus and E. coli and can be used on common plastics, medical devices, lenses and even ship hulls. Conventional methods for preventing bacterial surface attachment may use potentially harmful metal ions, nanoparticles, chemicals or UV-radiation.

Chemists have refuted a basic postulate of Förster theory, which describes energy transfers between pigment molecules, such as those that underlie photosynthesis. A revised version of the theory could have an impact on the design of optical computers and improve the efficiency of solar cells.

Viruses have a bad rep - and rightly so. The ability of a virus to quickly and precisely replicate itself makes it a destructive scourge to animals and plants alike. Now, researchers are turning the tables, harnessing and exploiting the "self-renewing" and "self-assembling" properties of viruses for a higher purpose: to build a new generation of small, powerful and highly efficient batteries and fuel cells.

Researchers have shown that a magnetically polarised current can be manipulated by electric fields. This important discovery opens up the prospect of simultaneously processing and storing data on electrons held in the molecular structure of computer chips - combining computer memory and processing power on the same chip.

Researchers have moved a step closer to creating robust, three-dimensional microbatteries that would charge faster and hold other advantages over conventional lithium-ion batteries. They could power new generations of remote sensors, display screens, smart cards, flexible electronics and biomedical devices. The batteries employ vertical arrays of nickel-tin nanowires perfectly encased in PMMA, a widely used polymer best known as Plexiglas.

Even smaller batteries - the world's smallest battery, as a matter of fact - consists of a single tin oxide nanowire anode 100 nanometers in diameter and 10 micrometers long, a bulk lithium cobalt oxide cathode three millimeters long, and an ionic liquid electrolyte. The device offers the ability to directly observe change in atomic structure during charging and discharging of the individual "trees."

Friday, December 3, 2010

This week in nanotechnology - December 3, 2010

IBM scientists this week unveiled a new chip technology - called CMOS Integrated Silicon Nanophotonics - that integrates electrical and optical devices on the same piece of silicon, enabling computer chips to communicate using pulses of light (instead of electrical signals), resulting in smaller, faster and more power-efficient chips than is possible with conventional technologies.

A group of Beckman Institute researchers have discovered a practical method for direct writing of metal lines less than five nanometers (5 nm) wide, a big step in creating contacts to and interconnects between nanoscale device structures like carbon nanotubes and graphene that have potential uses in electronics applications.

Researchers at Delft University of Technology and Oxford University announce a new type of nanopore device that could help in developing fast and cheap genetic analysis. They report on a novel method that combines man-made and biological materials to result in a tiny hole on a chip, which is able to measure and analyze single DNA molecules.
formation of hybrid pores by the directed insertion of the biological protein pore alpha hemolysin into solid-state nanopores

Artistic rendering of the formation of hybrid pores by the directed insertion of the biological protein pore alpha hemolysin (pink) into solid-state nanopores (holes in the green bottom layer). An applied electric field drives a double-stranded DNA molecule (blue, left) into the hole, which subsequently drags the pink hemolysin protein into position. Once assembled, these hybrid nanopores can be used to pull single-strand DNA (blue, center) through, for analysis and sequencing.

Emerging applications of carbon nanotubes: Researchers at MIT have published an overview of a variety of applications that are based on the unique properties of pristine as well as functionalized carbon nanotubes.
While the nanotechnology industry is expected to produce large quantities of nanoparticles in the near future, researchers have been worried about the environmental impact of the global nanotechnological revolution. Now, researchers found a method that could replace nearly all of the toxic chemicals required to make gold nanoparticles. The missing ingredient can be found in nearly every kitchen's spice cabinet - cinnamon.

A European consortium comprising National Physical Laboratory (NPL), ST Microelectronics, the University of Edinburgh, and TU Delft has been involved in the development and application of the Megaframe Imager - an ultrafast camera capable of recording images at the incredible rate of one million frames.

And finally for this week: free goodies! InTech, a multidisciplinary Open Access publisher of journals and books covering the fields of Science, Technology and Medicine, so far has published seven nanotechnology book titles that are available as free downloads.

Friday, November 26, 2010

This week in nanotechnology - November 26, 2010

A breakthrough in a University of Cincinnati engineering lab that could clear the way for a low-cost, even disposable, e-reader is gaining considerable attention. The researchers demonstrated that paper could be used as a flexible host material for an electrowetting device.

Methane-powered laptops may be closer than you think. Making fuel cells practical and affordable will not happen overnight. It may, however, not take much longer. With advances in nanostructured devices, lower operating temperatures, and the use of an abundant fuel source and cheaper materials, a group of researchers at the Harvard School of Engineering and Applied Sciences (SEAS) are increasingly optimistic about the commercial viability of the technology.

Oxygen rich graphene support could lead to durable fuel cell catalysts. In the search for efficient, durable and commercially viable fuel cells, scientists have discovered a new catalyst-support combination that could make fuel cells more efficient and more resistant to carbon monoxide poisoning.
Platinum nanocatalysts

Platinum nanocatalysts supported on lightly reduced graphene oxide could make fuel cells more stable and resistant to carbon monoxide poisoning.

Emerging applications of carbon nanotubes: Researchers at MIT have published an overview of a variety of applications that are based on the unique properties of pristine as well as functionalized carbon nanotubes.

Success in developing groundbreaking electrolyte materials for solid oxide fuel cells: The Fuel Cell Nano-Materials Group at the International Center for Materials Nanoarchitectonics in Japan has successfully developed two types of novel materials which satisfy all the three requirements for electrolyte: ion conductivity, chemical stability and sinterability, at high levels.

Ultrathin alternative to silicon for future electronics: Integrating ultra-thin layers of the semiconductor indium arsenide onto a silicon substrate leads to a nanoscale transistor with excellent electronic properties. A member of the III–V family of semiconductors, indium arsenide offers several advantages as an alternative to silicon including superior electron mobility and velocity, which makes it an oustanding candidate for future high-speed, low-power electronic devices.

Researchers are creating a system that harvests heat from an engine's exhaust to generate electricity, reducing a car's fuel consumption. Current thermoelectric technology cannot withstand the temperatures inside catalytic converters, where gases are about 1,000 degrees Celsius, he said. However, researchers also are working on new thermoelectrics capable of withstanding such high temperatures, a step that would enable greater fuel savings.

New YouTube videos explain graphene for the baffled. Two two short videos explain graphene and its amazing properties. The videos show how amazingly graphene can be produced using just a pencil and some sticky tape.

Friday, November 19, 2010

This week in nanotechnology - November 19, 2010

Engineers from Harvard University have designed and demonstrated ice-free nanostructured materials that literally repel water droplets before they even have the chance to freeze. The finding could lead to a new way to keep airplane wings, buildings, powerlines, and even entire highways free of ice during the worst winter weather. Moreover, integrating anti-ice technology right into a material is more efficient and sustainable than conventional solutions like chemical sprays, salt, and heating.

Sunlight represents the cleanest, greenest and far and away most abundant of all energy sources, and yet its potential remains woefully under-utilized. High costs have been a major deterrant to the large-scale applications of silicon-based solar cells. Nanopillars – densely packed nanoscale arrays of optically active semiconductors – have shown potential for providing a next generation of relatively cheap and scalable solar cells, but have been hampered by efficiency issues. The nanopillar story, however, has taken a new twist and the future for these materials now looks brighter than ever.

Nanotech teabag filter cleans water: Instead of being filled with black or green tea, the bag contains active carbon granules and is made from nanofibers treated with biocide, which kills bacteria rather than simply filtering them from the water.
teabag water filter

Each disposable filter can purify one liter of water.

Gene therapy holds the promise for curing a variety of diseases, including cancer, and nanoparticles have been recognized as promising vehicles for effective and safe delivery of genes into specific type of cells or tissues. However, the existing process available for producing and examining nanoparticles for this purpose is limited due to the use of conventional synthetic approaches that are cumbersome and time-consuming. UCLA researchers have now found a faster way to produce efficient nano-vehicles for gene delivery.

As electronics become smaller and smaller the need to understand nanoscale phenomena becomes greater and greater. Because materials exhibit different properties at the nanoscale than they do at larger scales, new techniques are required to understand and to exploit these new phenomena. A team of researchers led by Paul Weiss, UCLA's Fred Kavli Chair in NanoSystems Sciences, has developed a tool to study nanoscale interactions. Their device is a dual scanning tunneling and microwave-frequency probe that is capable of measuring the interactions between single molecules and the surfaces to which the molecules are attached.

Cancer scientists believe nanoparticles could accurately target tumors, avoiding side effects. Several nanoparticle drugs are now in clinical trials, and many more are being developed in research labs. These particles hold great potential to improve the performance of existing cancer drugs.

Friday, November 12, 2010

This week in nanotechnology - November 12, 2010

Low-cost, hybrid thermoelectrics: Historically, high-efficiency thermoelectrics have required high-cost, materials-intensive processing. By engineering a hybrid of soft and hard materials using straightforward flask chemistry in water, researchers at the Berkeley Lab have now developed a route that provides respectable efficiency with a low cost to production.

Andre Geim, who along with his colleague  Kostya Novoselov won the 2010 Nobel Prize for graphene, has now modified it to make fluorographene – a one-molecule-thick material chemically similar to Teflon. The team hope that fluorographene, which is a flat, crystal version of Teflon and is mechanically as strong as graphene, could be used as a thinner, lighter version of Teflon, but could also be in electronics, such as for new types of LED devices.

In other graphene news, Empa researchers have fabricated graphene-like materials using a surface chemical route and clarified in detail the corresponding reaction pathway. Understanding chemical reactions in detail helps to control them and enables to tailor graphene products.

The scanning tunnelling microscope images shows nanographene molecules and the two stabilized intermediate products on a copper surface. The molecular models show a nanographene (at the bottom right) as well as the two intermediate products (above and left). In reality the diameter of the molecule is approximately one nanometer.

Scientists at the Institute of Bioengineering and Nanotechnology in Singapore have devised a new environmentally friendly technique to transform carbon dioxide, an abundant and renewable carbon source, into highly functionalized propiolic acids, which are basic building blocks for the synthesis of a wide range of pharmaceuticals such as cholesterol-reducing drugs and peptidomimetic and other small molecule inhibitors that may be used, for example, to kill cancer cells.

Nanogenerators grow strong enough to power small conventional electronics: The nanogenerators devised in the laboratory of Zhong Lin Wang at Georgia Tech rely on the piezoelectric effect seen in crystalline materials such as zinc oxide, in which an electric charge potential is created when structures made from the material are flexed or compressed. By capturing and combining the charges from millions of these nanoscale zinc oxide wires, Wang and his research team can produce as much as three volts – and up to 300 nanoamps.

Quantum computers should be much easier to build than previously thought, because they can still work with a large number of faulty or even missing components. This surprising discovery brings scientists one step closer to designing and building real-life quantum computing systems – devices that could have enormous potential across a wide range of fields, from drug design, electronics, and even code-breaking.

A greener way to grow carbon nanotubes: It turns out that one process commonly used to produce carbon nanotubes may release several hundred tons of chemicals, including greenhouse gases and hazardous air pollutants, into the air each year. MIT researchers report that in experiments, removing one step in that process — a step that involves heating carbon-based gases and adding key reactive "ingredients" — reduced emissions of harmful by-products at least tenfold and, in some cases, by a factor of 100. It also cut the amount of energy used in the process by half.

Friday, November 5, 2010

This week in nanotechnology - November 5, 2010

Researchers at Oregon State University have solved a quest in fundamental material science that has eluded scientists since the 1960s, and could form the basis of a new approach to electronics. The discovery outlines the creation for the first time of a high-performance "metal-insulator-metal" diode. These diodes can be used to perform some of the same functions as silicon-based materials, but in a fundamentally different way.

A team of researchers at the University of Warwick has found molecular hooks on the surface of Graphene Oxide that will potentially provide massive benefits to researchers using transmission electron microscopes. They could even be used in building molecular scale mechanisms.

Scientists at Brookhaven National Laboratory and Los Alamos National Laboratory have fabricated transparent thin films capable of absorbing light and generating electric charge over a relatively large area. The material - which consists of a semiconducting polymer doped with carbon-rich fullerenes - could be used to develop transparent solar panels or even windows that absorb solar energy to generate electricity. Under carefully controlled conditions, the material self-assembles to form a reproducible pattern of micron-size hexagon-shaped cells over a relatively large area (up to several millimeters).
conjugated polymer honeycombTop: Scanning electron microscopy image and zoom of conjugated polymer (PPV) honeycomb. Bottom (left-to-right): Confocal fluorescence lifetime images of conjugated honeycomb, of polymer/fullerene honeycomb double layer and of polymer/fullerene honeycomb blend. Efficient charge transfer within the whole framework is observed in the case of polymer/fullerene honeycomb blend as a dramatic reduction in the fluorescence lifetime.

Radically simple technique developed to grow conducting polymer thin films: Oil and water don't mix, but add in some nanofibers and all bets are off. A team of UCLA chemists and engineers has developed a new method for coating large surfaces with nanofiber thin films that are both transparent and electrically conductive. Their method involves the vigorous agitation of water, dense oil and polymer nanofibers. After this solution is sufficiently agitated it spreads over virtually any surface, creating a film.

Engineers have discovered a new method to speed the production rate of nanoparticles by 500 times, an advance that could play an important role in making nanotechnology products more commercially practical. The approach uses an arrayed microchannel reactor and a "laminated architecture" in which many sheets, each with thousands of microchannels in them, are stacked in parallel to provide a high volume of production and excellent control of the processes involved.

Remember the Star Wars scene in which R2D2 projects a three-dimensional image of a troubled Princess Leia delivering a call for help to Luke Skywalker and his allies? What used to be science fiction is now close to becoming reality thanks to a breakthrough in 3D holographic imaging technology developed at the University of Arizona College of Optical Sciences.

Friday, October 29, 2010

This week in nanotechnology - October 29, 2010

Researchers at the University of Pennsylvania have developed a new electronic method for detecting microRNA isolated from living cells. MicroRNAs are a class of small biomolecules that control gene expression into proteins, the "workers" of the cell. MicroRNAs act by binding to specific messenger RNAs that code for proteins, and, by doing so, inhibit protein synthesis.

Bone consists of fibers of collagen in which calcium phosphate is deposited in the form of nanocrystals. Researchers at Eindhoven University of Technology have for the first time succeeded in mimicking the process of bone formation in the laboratory, and in visualizing the process in great detail.

EU research initiative called 'Steeper'aims to increase electronic device efficiency by 10x and eliminate power consumption of devices in standby mode. Scientists collaborating on the project will apply their expertise and research to tunnel field effect transistors (TFETs) and semiconducting nanowires to improve the efficient use of energy in electronics. To explain the challenge, consider a leaky water faucet -- even after closing the valve as far as possible water continues to drip -- this is similar to today's transistor, in that energy is constantly "leaking" or being lost or wasted in the off-state. In Steeper, scientists not only hope to contain the leak by using a new method to close the valve or gate of the transistor more tightly, but also open and close the gate for maximum current flow with less turns, i.e. less voltage for maximum efficiency.

Researchers from North Carolina State University have found a way to optimize the development of DNA self-assembling materials, which hold promise for technologies ranging from drug delivery to molecular sensors.

buckyballs in space

And some fun fact at the end: Astronomers have discovered bucket loads of buckyballs in space. They used NASA's Spitzer Space Telescope to find the little carbon spheres throughout our Milky Way galaxy – in the space between stars and around three dying stars. What's more, Spitzer detected buckyballs around a fourth dying star in a nearby galaxy in staggering quantities – the equivalent in mass to about 15 of our moons.

Friday, October 22, 2010

This week in nanotechnology, October 22, 2010

Scientists have captured the first direct images of magnetic monopoles which were theoretically conceived by the British-Swiss physicist Dirac in the early 1930s who showed that their existence is consistent with the ultimate theory of matter – quantum theory.

For the first time scientists have been able to watch nanoparticles grow from the earliest stages of their formation. Nanoparticles are the foundation of nanotechnology and their performance depends on their structure, composition, and size. Researchers will now be able to develop ways to control conditions under which they are grown. The breakthrough will affect a wide range of applications including solar-cell technology and chemical and biological sensors.
bacterial nanowire

This image shows nanoparticles growing.

Photonic crystals are exotic materials with the ability to guide light beams through confined spaces and could be vital components of low-power computer chips that use light instead of electricity. Cost-effective ways of producing them have proved elusive, but researchers have recently been turning toward a surprising source for help: DNA molecules. The researchers demonstrated that tiny particles of gold and balls of protein known as virus-like particles, both with strands of DNA attached to them, would spontaneously organize themselves into a lattice-like structure. Although the materials themselves aren't useful for making photonic crystals, the distances between the particles are exactly those that would enable a photonic crystal to guide light in the visible spectrum.

Nature has one very big advantage over any human research team: plenty of time. Billions of years, in fact. And over all that time, it has produced some truly amazing materials — using weak building blocks that human engineers have not yet figured out how to use for high-tech applications, and with many properties that humans have yet to find ways to duplicate. But now a number of researchers have begun to unravel these processes at a deep level, not just finding out how the materials behave but what the essential structural and chemical characteristics are that give them their unique properties. In the future, they hope to mimic those structures in ways that produce even better results.

Twisting spires, concentric rings, and gracefully bending petals are a few of the new three-dimensional shapes that University of Michigan engineers can make from carbon nanotubes using a new manufacturing process. The process is called "capillary forming", and it takes advantage of capillary action, the phenomenon at work when liquids seem to defy gravity and travel up a drinking straw of their own accord.
bacterial nanowire

Twisting spires are one of the 3D shapes researchers were able to develop using a new manufacturing process.

University of Virginia chemical engineers have uncovered the key features that control the high reactivity of gold nanoparticles in a process that oxidizes alcohols in water. The research is an important first step in unlocking the potential of using metal catalysts for developing biorenewable chemicals.

Scientists take first step toward electronically interfacing microbes with inorganic materials. The Terminator. The Borg. The Six Million Dollar Man. Science fiction is ripe with biological beings armed with artificial capabilities. In reality, however, the clunky connections between living and non-living worlds often lack a clear channel for communication. Now, scientists with the Berkeley Lab have designed an electrical link to living cells engineered to shuttle electrons across a cell's membrane to an external acceptor along a well-defined path. This direct channel could yield cells that can read and respond to electronic signals, electronics capable of self-replication and repair, or efficiently transfer sunlight into electricity.

Friday, October 15, 2010

This week in nanotechnology - October 15, 2010

Scientists have developed a novel nano-tomography method, which uses X-rays to allow doctors to produce three-dimensional (3D) detailed imaging of fragile bone structures. This method could lead to the development of better therapeutic approaches to tackle the brittle bone disease osteoporosis, one of the most common disorders among older people.

Some bacteria grow electrical hair that lets them link up in big biological circuits, according to a University of Southern California biophysicist and his collaborators. The finding suggests that microbial colonies may survive, communicate and share energy in part through electrically conducting hairs known as bacterial nanowires.
bacterial nanowire

Like human hair, a bacterial nanowire consists mostly of protein.

Rice University research that capitalizes on the wide-ranging capabilities of graphene could lead to circuit applications that are far more compact and versatile than what is now feasible with silicon-based technologies. Triple-mode, single-transistor amplifiers based on graphene -- the one-atom-thick form of carbon that recently won its discoverers a Nobel Prize -- could become key components in future electronic circuits.

Researchers at the Georgia Institute of Technology and Emory University have developed a novel approach for delivering small bits of genetic material into the body to improve the treatment of inflammatory bowel diseases. Delivering short strands of RNA into cells has become a popular research area because of its potential therapeutic applications, but how to deliver them into targeted cells in a living organism has been an obstacle. The team encapsulated short pieces of RNA into engineered particles called thioketal nanoparticles and orally delivered the genetic material directly to the inflamed intestines of animals.

Tyndall National Institute, UCC announced the development of a new nanomaterial that will dramatically reduce the operating temperature of silicon chip components and circuits, thereby enhancing the reliability and lifetime of electronics in products ranging from smart phones to automotive electronics.

Friday, October 8, 2010

This week in nanotechnology, October 8, 2010

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2010 to Andre Geim and Konstantin Novoselov, University of Manchester, "for groundbreaking experiments regarding the two-dimensional material graphene".

In recent years, studies have shown that for many types of cancer, combination drug therapy is more effective than single drugs. However, it is usually difficult to get the right amount of each drug to the tumor. Now researchers at MIT and Brigham and Women's Hospital have developed a nanoparticle that can deliver precise doses of two or more drugs to prostate cancer cells.

The enigmatic Möbius strip has long been an object of fascination, appearing in numerous works of art, most famously a woodcut by M.C. Escher, in which a tribe of ants traverses the form's single, never-ending surface. Scientists have now reproduced a nanoscale Möbius strip, joining up braid-like segments of DNA to create Möbius structures measuring just 50 nanometers across—roughly the width of a virus particle. Eventually, researchers hope to capitalize on the unique material properties of such nano-architectures, applying them to the development of biological and chemical sensing devices, nanolithography, drug delivery mechanisms pared down to the molecular scale and a new breed of nanoelectronics.
nanoscale DNA Möbius strip
This is the design for the DNA Möbius strip. Single-stranded viral DNA is used as scaffolding and 164 short segments of DNA are used as staple strands, to create the nanostructure. The Möbius form is composed of eleven double helices, assembled in parallel (left). Each double-helical length contains a twist of 180 degrees along its central axis, before it seamlessly reconnects with itself. The central helix, (seen in red) circles around the length of the strip once. The other helices circle twice, while also twisting around the core helix by 180 degrees before reconnecting to close the Möbius loop. (Center) A small segment of the strip with the details of the helices shown. Scaffold strands are seen in blue and staple strands are different colors. To create the Möbius, 20.5 units like this were used, with the precise folding pattern pre-programmed through the design of appropriate nucleotide base-pairing. (Right) Atomic Force Microscopy image.

Early detection is critical for improving cancer survival rates. Yet, one of the deadliest cancers in the United States, lung cancer, is notoriously difficult to detect in its early stages. Now, researchers have developed a method to detect lung cancer by merely shining diffuse light on cells swabbed from patients' cheeks. Nanoscale disturbances in cheek cells indicate the presence of lung cancer. Regular microscopy looking at chromatin, the genetic material inside a cell's nucleus, will not reveal significant dissimilarities between the cheek cells of a healthy person and those of a lung cancer patient. However, a new technique called partial wave spectroscopic microscopy (PWS) zeroes in on smaller-than-microscopic disturbances at the nano-level, which are harbingers of trouble.

Cornell researchers have developed a new method to create a patterned single-crystal thin film of semiconductor material that could lead to more efficient photovoltaic cells and batteries. The "holy grail" for such applications has been to create on a silicon base, or substrate, a film with a 3-D structure at the nanoscale, with the crystal lattice of the film aligned in the same direction (epitaxially) as in the substrate. Doing so is the culmination of years of research into using polymer chemistry to create nanoscale self-assembling structures.

Friday, October 1, 2010

This week in nanotechnology - October 1, 2010

A 'forest' of molecules holds the promise of turning waste heat into electricity. What do a car engine, a power plant, a factory and a solar panel have in common? They all generate heat – a lot of which is wasted. University of Arizona physicists have discovered a new way of harvesting waste heat and turning it into electrical power. Unlike existing heat-conversion devices such as refrigerators and steam turbines, the new devices of require no mechanics and no ozone-depleting chemicals. Instead, a rubber-like polymer sandwiched between two metals acting as electrodes can do the trick.

Researchers at IBM have added a new measurement method to their toolkit to capture ultra-fast phenomena on individual nano-objects. The ability to measure nanosecond-fast phenomena opens a new realm of experiments for scientists, since they can now add the dimension of time to experiments in which extremely fast changes occur.

In a major physics breakthrough with international significance, scientists have developed a technique to consistently isolate and capture a fast-moving neutral atom – and have also seen and photographed this atom for the first time. The researchers used laser cooling technology to dramatically slow a group of rubidium 85 atoms. A laser-beam, or "optical tweezers", was then deployed to isolate and hold one atom - at which point it could be photographed through a microscope.

Graphene may hold key to speeding up DNA sequencing - researchers from Harvard University and MIT have demonstrated that graphene, a surprisingly robust planar sheet of carbon just one-atom thick, can act as an artificial membrane separating two liquid reservoirs. By drilling a tiny pore just a few-nanometers in diameter, called a nanopore, in the graphene membrane, the researchers were able to measure exchange of ions through the pore and demonstrate that a long DNA molecule can be pulled through the graphene nanopore just as a thread is pulled through the eye of a needle.

A layer of graphene is shown with a tiny nanopore drilled into its surface

A layer of graphene is shown with a tiny nanopore drilled into its surface. Researchers at Harvard and MIT say the membrane holds potential for speeding up DNA sequencing due to its extreme thinness.

Getting an inside look at the center of a cell can be as easy as a needle prick, thanks to University of Illinois researchers who have developed a tiny needle to deliver a shot right to a cell's nucleus. The team developed a nanoneedle that also served as an electrode that could deliver quantum dots directly into the nucleus of a cell – specifically to a pinpointed location within the nucleus.

Scientists report the first successful assembly of 3-D multi-component nanoscale structures with tunable optical properties that incorporate light-absorbing and -emitting particles. This work, using synthetic DNA as a programmable component to link the nanoparticles, demonstrates the versatility of DNA-based nanotechnology for the fabrication of functional classes of materials, particularly optical ones, with possible applications in solar-energy conversion devices, sensors, and nanoscale circuits.

Friday, September 24, 2010

This week in nanotechnology - September 24, 2010

Is this the end of microplates? Novel nanoelectronic biosensing technology could facilitate new era of personalized medicine. The multi-welled microplate, long a standard tool in biomedical research and diagnostic laboratories, could become a thing of the past thanks to new electronic biosensing technology developed by a team of microelectronics engineers and biomedical scientists at the Georgia Institute of Technology.

The new electronic microplate is shown in front of the technology it aims to replace, the conventional microplate
The new electronic microplate is shown in front of the technology it aims to replace, the conventional microplate.

A nanoparticle-based catalyst developed at Rice University may give that tiger in your tank a little more roar. A new paper details a process that should help oil refineries make the process of manufacturing gasoline more efficient and better for the environment. The researchers found that sub-nanometer clusters of tungsten oxide lying on top of zirconium oxide are a highly efficient catalyst that turns straight-line molecules of n-pentane, one of many hydrocarbons in gasoline, into better-burning branched n-pentane.

A team of Yale physicists has used lasers to cool molecules down to temperatures near what's known as absolute zero, about -460 degrees Fahrenheit. Their new method for laser cooling is a significant step toward the ultimate goal of using individual molecules as information bits in quantum computing.

plasmons in a pair of gold nanotips concentrate light from a laser, amplifying it by a factor of 1,000
This artist's rendering shows how plasmons in a pair of gold nanotips concentrate light from a laser, amplifying it by a factor of 1,000.

Condensed matter physicists have found a way to make an optical antenna from two gold tips separated by a gap less than a nanometer wide, that gathers light from a laser. The tips grab the light and concentrate it down into a tiny space, leading to a thousand-fold increase in light intensity in the gap. Putting the nanotips so close together allows charge to flow via quantum tunneling as the electrons are pushed from one side to the other.

A novel nano-tomography method opens the door to computed tomography examinations of minute structures at nanometer resolutions. Three-dimensional detailed imaging of fragile bone structures becomes possible. This new technique will facilitate advances in both life sciences and materials sciences.
Schematic of the new nano-CT method. The sample is scanned with an X-ray beam while the detector records a diffraction pattern for every beam position. The sample is then turned around its axis and scanned again, until a complete set of data is gathered for every angle. A high-resolution three-dimensional image of the sample is then computed from the hundreds of thousands of diffraction patterns by means of specially developed image reconstruction algorithms.

Researchers have come up with an intriguing new class of molecular probes for biomedical research called nanoLAMPs. Unlike most probes used in biomedicine or other types of research they don't require dyes or fluorescence but, like an ordinary house lamp, they do need a light switch in order to illuminate the molecular world. These nanoLAMPs, which stands for Nano-Layered Metal-dielectric Particles, can solve a problem in biomedical research: the inability to measure multiple molecules simultaneously with a high degree of accuracy and reliability.

Computers, light bulbs, and even people generate heat—energy that ends up being wasted. With a thermoelectric device, which converts heat to electricity and vice versa, you can harness that otherwise wasted energy. Researchers at Caltech have developed a new type of material - made out of silicon, the second most abundant element in Earth's crust - that could lead to more efficient thermoelectric devices.

Friday, September 17, 2010

This week in nanotechnology - September 17, 2010

Graphene may hold key to speeding up DNA sequencing. Researchers from Harvard University and MIT have demonstrated that graphene, a surprisingly robust planar sheet of carbon just one-atom thick, can act as an artificial membrane separating two liquid reservoirs. By drilling a tiny pore just a few-nanometers in diameter, called a nanopore, in the graphene membrane, they were able to measure exchange of ions through the pore and demonstrated that a long DNA molecule can be pulled through the graphene nanopore just as a thread is pulled through the eye of a needle.

artificial e-skin with nanowire active matrix circuitry covering a hand
An artist's illustration of an artificial e-skin with nanowire active matrix circuitry covering a hand. The fragile egg illustrates the functionality of the e-skin device for prosthetic and robotic applications.

Engineers make artificial skin out of nanowires. Engineers at UC Berkeley, have developed a pressure-sensitive electronic material from semiconductor nanowires that could one day give new meaning to the term "thin-skinned." A touch-sensitive artificial skin would help overcome a key challenge in robotics: adapting the amount of force needed to hold and manipulate a wide range of objects.

Using carbon nanotubes, MIT chemical engineers have found a way to concentrate solar energy 100 times more than a regular photovoltaic cell. Such nanotubes could form antennas that capture and focus light energy, potentially allowing much smaller and more powerful solar arrays.

Molecular machines can be found everywhere in nature, for example, transporting proteins through cells and aiding metabolism. To develop artificial molecular machines, scientists need to understand the rules that govern mechanics at the molecular or nanometer scale. To address this challenge, a research team at UC Riverside studied a class of molecular machines that 'walk' across a flat metal surface. They considered both bipedal machines that walk on two 'legs' and quadrupedal ones that walk on four.

aregions on a cathode surface display varying electrochemical behaviors when probed with ESM
This 1 micron x 1 micron composite image demonstrates how regions on a cathode surface display varying electrochemical behaviors when probed with ESM.

As industries and consumers increasingly seek improved battery power sources, cutting-edge microscopy performed at the Department of Energy's Oak Ridge National Laboratory is providing an unprecedented perspective on how lithium-ion batteries function. They have developed a new type of scanning probe microscopy called electrochemical strain microscopy (ESM) to examine the movement of lithium ions through a battery's cathode material.

A Florida State University engineering professor's innovative research with nanomaterials could one day lead to a new generation of hydrogen fuel cells that are less expensive, smaller, lighter and more durable. Working with carbon nanotubes, he has designed a membrane that could reduce the need for expensive platinum components in hydrogen fuel cells.

quantum tornado
A flat wave (left) meets the specially shaped grid screen, which converts the electron beam into right-rotating and left-rotating vortex beams (top and bottom), and a middle beam that does not rotate. Similar to in a tornado, the rotation of the electron current is low internally.

Manipulating materials with rotating quantum particles: a team from the University of Antwerp and TU Vienna has succeeded in producing what are known as vortex beams - rotating electron beams, which make it possible to investigate the magnetic properties of materials. In the future, it may even be possible to manipulate the tiniest components in a targeted manner and set them in rotation.

Researchers at Oregon State University have reported the successful loading of biological molecules onto "nanosprings" - a type of nanostructure that has gained significant interest in recent years for its ability to maximize surface area in microreactors. Nanosprings are a little like a miniature version of an old-fashioned, curled-up phone cord. They make a great support on which to place reactive catalysts, and there are a variety of potential applications.

The ability of phase-change materials to readily and swiftly transition between different phases has made them valuable as a low-power source of non-volatile or "flash" memory and data storage. Now an entire new class of phase-change materials has been discovered that could be applied to phase change random access memory (PCM) technologies and possibly optical data storage as well. The new phase-change materials – nanocrystal alloys of a metal and semiconductor – are called "BEANs," for binary eutectic-alloy nanostructures.

Friday, September 10, 2010

This week in nanotechnology - September 10, 2010

Researchers create new self-assembling photovoltaic technology that repairs itself. Plants are good at doing what scientists and engineers have been struggling to do for decades: converting sunlight into stored energy, and doing so reliably day after day, year after year. Now some MIT scientists have succeeded in mimicking a key aspect of that process. Plants constantly break down their light-capturing molecules and reassemble them from scratch, so the basic structures that capture the sun's energy are, in effect, always brand new.

Researchers from ETH Zurich's Institute for Field Theory and High Frequency Electronics have developed new surfaces for radar absorption. Thanks to this multifaceted application, window panes could even double up as solar panels in future. The researchers have devised a new method to produce surfaces that can absorb radar radiation over an extremely broad range.
new metamaterials are particularly efficient at absorbing radar radiation through a recurring pattern of copper plates and holes.

The new metamaterials are particularly efficient at absorbing radar radiation through a recurring pattern of copper plates and holes.

A North Carolina State University researcher and colleagues have figured out a way to make an aluminum alloy, or a mixture of aluminum and other elements, just as strong as steel. The aluminum alloys have unique structural elements that, when combined to form a hierarchical structure at several nanoscale levels, make them super-strong and ductile.

Scientists have discovered that electrons in graphene can split up into an unexpected and tantalizing set of energy levels when exposed to extremely low temperatures and extremely high magnetic fields. The new research raises several intriguing questions about the fundamental physics of this exciting material and reveals new effects that may make graphene even more powerful than previously expected for practical applications.

For the first time, a team of MIT chemical engineers has observed single ions marching through a tiny carbon-nanotube channel. Such channels could be used as extremely sensitive detectors or as part of a new water-desalination system. They could also allow scientists to study chemical reactions at the single-molecule level.

Friday, September 3, 2010

This week in nanotechnology - September 3, 2010

Sugar, salt, alcohol and a little serendipity led a Northwestern University research team to discover a new class of nanostructures that could be used for gas storage and food and medical technologies. And the compounds are edible. The porous crystals are the first known all-natural metal-organic frameworks (MOFs) that are simple to make. Most other MOFs are made from petroleum-based ingredients, but the Northwestern MOFs you can pop into your mouth and eat, and the researchers have.

Silicon oxide nanoelectronics circuits break barrier. Scientists at Rice University have created the first two-terminal memory chips that use only silicon, one of the most common substances on the planet, in a way that should be easily adaptable to nanoelectronic manufacturing techniques and promises to extend the limits of miniaturization subject to Moore's Law.

Playing snooker with atoms. Scientists speak of sputtering when energy-rich ions hit a solid object and cause atoms to be released from its surface. The phenomenon can be exploited to apply microscopically thin coatings to glass surfaces. A research team has developed a special sputtering technique that greatly increases the efficiency of the coating process.

One of the most difficult aspects of working at the nanoscale is actually seeing the object being worked on. Biological structures like viruses, which are smaller than the wavelength of light, are invisible to standard optical microscopes and difficult to capture in their native form with other imaging techniques. A multidisciplinary research group at UCLA has now teamed up to not only visualize a virus but to use the results to adapt the virus so that it can deliver medication instead of disease.

To watch a magician transform a vase of flowers into a rabbit, it's best to have a front-row seat. Likewise, for chemical transformations in solution, the best view belongs to the molecular spectators closest to the action. Those special molecules comprise the "first solvation shell," and although it has been known for decades that they can sense and dictate the fate of nearly every chemical reaction, it has been virtually impossible to watch them respond. University of Michigan researchers Kevin Kubarych and Carlos Baiz, however, recently achieved the feat.
An optical microscopy image of seven color filters illuminated by white microscope light

The molecules shown here in yellow are first-hand observers to an ultrafast chemical reaction. As the reaction proceeds, the vibrational frequencies of the yellow molecules change. By "listening" to changes in these vibrational frequencies, researchers could observe the chemical reaction underway. The rainbow colors indicate how the "notes" of the yellow molecules change in response to the reaction.

Physicists at the National Institute of Standards and Technology have used a small crystal of ions (electrically charged atoms) to detect forces at the scale of yoctonewtons - that's 0.000000000000000000000001 Newtons. The ion sensor works by examining how an applied force affects ion motion, based on changes in laser light reflected off the ions.

Researchers at Georgia Tech have developed a new class of electronic logic device in which current is switched by an electric field generated by the application of mechanical strain to zinc oxide nanowires. The devices, which include transistors and diodes, could be used in nanometer-scale robotics, nano-electromechanical systems (NEMS), micro-electromechanical systems (MEMS) and microfluidic devices. The mechanical action used to initiate the strain could be as simple as pushing a button, or be created by the flow of a liquid, stretching of muscles or the movement of a robotic component.

Researchers at Caltech have devised a new technique - using a sheet of carbon just one atom thick - to visualize the structure of molecules. The technique, which was used to obtain the first direct images of how water coats surfaces at room temperature, can also be used to image a potentially unlimited number of other molecules, including antibodies and other biomolecules.

Friday, August 27, 2010

This week in nanotechnology - August 27, 2010

Scientists and engineers seek to meet three goals in the production of biofuels from non-edible sources such as microalgae: efficiency, economical production and ecological sustainability. Syracuse University researchers have uncovered a process that is a promising step toward accomplishing these three goals. They have discovered a method to make algae, which can be used in the production of biofuels, grow faster by manipulating light particles through the use of nanobiotechnology. By creating accelerated photosynthesis, algae will grow faster with minimal change in the ecological resources required.

Just as cilia lining the lungs help keep passages clear by moving particles along the tips of the tiny hair-structures, man-made miniscule bristles known as nano-brushes can help reduce friction along surfaces at the molecular level, among other things. In their latest series of experiments, Duke University engineers have developed a novel approach to synthesize these nano-brushes, which could improve their versatility in the future. These polymer brushes are currently being used in biologic sensors and microscopic devices, such as microcantilevers, and they will play an important role in the future drive to miniaturization, the researchers said.

In a step toward more efficient, smaller and higher-definition display screens, a University of Michigan professor has developed a new type of color filter made of nano-thin sheets of metal with precisely spaced gratings. The gratings, sliced into metal-dielectric-metal stacks, act as resonators. They trap and transmit light of a particular color, or wavelength. Simply by changing the space between the slits, the researchers can generate different colors. Through nanostructuring, they can render white light any color.

An optical microscopy image of seven color filters illuminated by white microscope light

An optical microscopy image of seven color filters illuminated by white microscope light.

If a drug can be guided to the right place in the body, the treatment is more effective and there are fewer side-effects. Researchers at Lund University in Sweden have now developed magnetic nanoparticles that can be directed to metallic implants such as artificial knee joints, hip joints and stents in the coronary arteries. The team has shown that the principle works in animal experiments. They have succeeded in attaching a clot-dissolving drug to the nanoparticles and, with the help of magnets, have directed the particles to a blood clot in a stent in the heart to dissolve it. Thus the nanoparticles have been able to stop an incipient heart attack.

Researchers from North Carolina State University have developed extremely small microneedles that can be used to deliver medically-relevant nanoscale dyes called quantum dots into skin – an advance that opens the door to new techniques for diagnosing and treating a variety of medical conditions, including skin cancer.

Using a cutting edge nanotechnology, researchers at MIT have created a robotic prototype that could autonomously navigate the surface of the ocean to collect surface oil and process it on site. The system, called Seaswarm, is a fleet of vehicles that may make cleaning up future oil spills both less expensive and more efficient than current skimming methods.

NanoEngineers at the University of California, San Diego are designing new types of lithium-ion (Li-ion) batteries that could be used in a variety of NASA space exploration projects – and in a wide range of transportation and consumer applications. The nearly $600,000 program builds upon expertise in the UC San Diego Department of NanoEngineering in modeling new nanocomposite structures for next generation electrode materials, and NEI's capability to reproducibly synthesize electrode materials at the nanoscale.

Friday, August 20, 2010

This week in nanotechnology - August 20, 2010

Researchers demonstrate that non-viral gene therapy can delay the onset of some forms of eye disease and preserve vision. The team developed nanoparticles to deliver therapeutic genes to the retina and found that treated mice temporarily retained more eyesight than controls.

Nanocorrosion causes implants to fail. Extra-hard coatings made from diamond-like carbon (DLC) extend the operating lifetime of tools and components. In artificial joints, however, these coatings often fail because they detach. Empa researchers found out why – and developed methods to both make the interface between the DLC layer and the metal underneath corrosion-resistant and to predict the lifetime of the implants.

Ultra- or supercapacitors are emerging as a key enabling storage technology for use in fuel-efficient transport as well as in renewable energy. Engineers hope that supercapacitors can bridge the gap between batteries and electrolytic capacitors, but contemporary devices have a lower specific energy than Li-ion batteries and are orders of magnitude slower than electrolytic capacitors. Researchers have now shown that by moving from porous carbon with a network of pores inside particles as electrode material to exposed surfaces of nanostructured carbon onions of 6-7 nm diameter, it is possible to reach the discharge rate (power) of electrolytic capacitors, but with volumetric capacitance about four orders of magnitude higher.

Clinical trials using patients' own immune cells to target tumors have yielded promising results. However, this approach usually works only if the patients also receive large doses of drugs designed to help immune cells multiply rapidly, and those drugs have life-threatening side effects. Now a team of MIT engineers has devised a way to deliver the necessary drugs by smuggling them on the backs of the cells sent in to fight the tumor. That way, the drugs reach only their intended targets, greatly reducing the risk to the patient.

drug-carrying pouches attached to the surfaces of cells

Engineers have developed a way to attach drug-carrying pouches (yellow) to the surfaces of cells.

As semiconductor manufacturers build ever smaller components, circuits and chips at the nano scale become less reliable and more expensive to produce. The variability in their behavior from device to device and over their lifetimes – due to manufacturing, aging-related wear-out, and varying operating environments – is largely ignored by today's mainstream computer systems. Now a visionary team of computer scientists and electrical engineers from six universities is proposing to deal with the downside of nanoscale computer components by re-thinking and enhancing the role that software can play in a new class of computing machines that are adaptive and highly energy efficient.

Friday, August 13, 2010

This wek in nanotechnology - August 13, 2010

Scientists can detect the movements of single molecules by using fluorescent tags or by pulling them in delicate force measurements, but only for a few minutes. A new technique by Rice University researchers will allow them to track single molecules without modifying them – and it works over longer timescales.

Chemists and engineers at Harvard University have fashioned nanowires into a new type of V-shaped transistor small enough to be used for sensitive probing of the interior of cells. The new device is smaller than many viruses and about one-hundredth the width of the probes now used to take cellular measurements, which can be nearly as large as the cells themselves. Its slenderness is a marked improvement over these bulkier probes, which can damage cells upon insertion, reducing the accuracy or reliability of any data gained.

Under the microscope, the bacteria start dividing normally, two cells become four and then eight and so on. But then individual cells begin "popping," like circus balloons being struck by darts. This phenomenon, which surprised the Duke University bioengineers who captured it on video, turns out to be an example of a more generalized occurrence that must be considered by scientists creating living, synthetic circuits out of bacteria. Even when given the same orders, no two cells will behave the same. The researchers believe this accidental finding of a circuit they call "ePop" can help increase the efficiency and power of future synthetic biology circuits.

A new test for oral cancer, which a dentist could perform by simply using a brush to collect cells from a patient´s mouth, is set to be developed by researchers at the University of Sheffield and Sheffield Teaching Hospitals NHS Foundation Trust. The nano-bio-chips are disposable and slotted like a credit card into a battery-powered analyser.

Researchers at Ohio State University have demonstrated the first plastic computer memory device that utilizes the spin of electrons to read and write data. An alternative to traditional microelectronics, so-called "spintronics" could store more data in less space, process data faster, and consume less power.

Researchers have taken one more step toward understanding the unique and often unexpected properties of graphene, a two-dimensional carbon material that has attracted interest because of its potential applications in future generations of electronic devices. They describe for the first time how the orbits of electrons are distributed spatially by magnetic fields applied to layers of epitaxial graphene.

It turns out that watching paint dry might not be as boring as the old adage claims. A team led by Yale University researchers has come up with a new technique to study the mechanics of coatings as they dry and peel, and has discovered that the process is far from mundane. They present a new way to image and analyze the mechanical stress that causes colloidal coatings – those in which microscopic particles of one substance are dispersed throughout another – to peel off of surfaces.

A "smart" nanomaterial recently developed at the University of Dayton Research Institute for multi-purpose use in aircraft coatings, wind turbines and other large-scale commercial applications may also lead to a significant breakthrough in glaucoma treatment. Nicknamed "fuzzy fiber", the tailored carbon material is expected to improve the lives of glaucoma sufferers by reducing the number of medical procedures needed to treat the disease.

Friday, August 6, 2010

This week in nanotechnology - August 6, 2010

One Chicago skyline is dazzling enough. Now imagine 15,000 of them.
A Northwestern University research team has done just that -- drawing 15,000 identical skylines with tiny beams of light using an innovative nanofabrication technology called beam-pen lithography (BPL). The technology offers a means to rapidly and inexpensively make and prototype circuits, optoelectronics and medical diagnostics and promises many other applications in the electronics, photonics and life sciences industries.

Nanoparticle-coated pavement that cleans the air: The concentrations of toxic nitrogen oxide that are present in German cities regularly exceed the maximum permitted levels. That's now about to change, as innovative paving slabs that will help protect the environment are being introduced. Coated in titanium dioxide nanoparticles, they reduce the amount of nitrogen oxide in the air.

A newly discovered nanomaterial – silicon nanoneedles with modulated porosity – could improve healthcare devices by increasing energy storage, help realize implantable microchips or make better drugs. The nanoporous needles are flexible, semiconductors, biodegradable and have a surface one hundred times larger that of solid nanowires. These unique properties of the nanowires will provide a higher energy density when used as large surface anodes in lithium batteries, constitute the active elements of bioresorbable, flexible microchips for subcutaneous implants or protect drugs while in the body and release them in a controlled manner to improve their therapeutic effect.

atomically-thin graphene nanopores

Left: A side view of a forest of bicolor nanoneedles. A central low porosity segment is green and two siding high porosity segments are red. An ultrathin porous wire crosses the picture sideways, in yellow. Middle: Bicolor nanoneedles seen from an angle. The high porosity segment is red and low porosity segment is green. The grass-like flexibility of the nanowires allows the tips to join. Right: A forest of evenly spaced cylindrical nanoneedles. The diameter is 100nm and allows piercing of cell membrane without harming the cells.

In an innovation critical to improved DNA sequencing, a markedly slower transmission of DNA through nanopores has been achieved. Solid-state nanopores sculpted from silicon dioxide are generally straight. They are used as sensors to detect and characterize DNA, RNA and proteins. But these materials shoot through such holes so rapidly that sequencing the DNA passing through them is a problem. Researchers now report using self-assembly techniques to fabricate equally tiny but kinked nanopores which achieve a fivefold slowdown in the voltage-driven translocation speeds critically needed in DNA sequencing.

For the first time ever, scientists watch an atom's electrons moving in real time. The researchers used ultrashort flashes of laser light to directly observe the movement of an atom's outer electrons for the first time. Through a process called attosecond absorption spectroscopy, researchers were able to time the oscillations between simultaneously produced quantum states of valence electrons with great precision. These oscillations drive electron motion.

While most most polymer solar cells are manufactured through a spin-coating process – a technology very useful for fabricating very thin and homogeneous film and for controlling the film thickness – spin-coating has several drawbacks with regard to its application to mass production: scale-up is problematic and the process is not continuous; it is impossible to fabricate flexible devices; the process is not only expensive and wasteful but the cost increases exponentially as the substrate size increases. To overcome these problems, researchers have now introduced a highly efficient polymer solar cell fabrication method by a novel coating process – roller painting.

Friday, July 30, 2010

This week in nanotechnology - July 30, 2010

Spotting a single cancerous cell that has broken free from a tumor and is traveling through the bloodstream to colonize a new organ might seem like finding a needle in a haystack. But a new imaging technique from the University of Washington is a first step toward making this possible. Researchers have developed a multifunctional nanoparticle that eliminates the background noise, enabling a more precise form of medical imaging – essentially erasing the haystack, so the needle shines through.

Imagine a device the size of – and nearly as cheap as – a grain of sand which is capable of analyzing the environment around it, recognize its chemical composition, and report it to a monitoring system. Researchers have now demonstrated a method to design prospective simple sensing arrays - so-called electronic noses - which, in principle, might be scaled down to the size of few micrometers and thus become the smallest analytical instrument.

First step towards electronic DNA sequencing: Translocation through graphene nanopores. Researchers at the University of Pennsylvania have developed a new, carbon-based nanoscale platform to electrically detect single DNA molecules. Using electric fields, the tiny DNA strands are pushed through nanoscale-sized, atomically thin pores in a graphene nanopore platform that ultimately may be important for fast electronic sequencing of the four chemical bases of DNA based on their unique electrical signature.

atomically-thin graphene nanopores

Electric fields push tiny DNA strands through atomically-thin graphene nanopores that ultimately may sequence DNA bases by their unique electrical signature.

By linking individual semiconductor quantum dots with gold nanoparticles, scientists have demonstrated the ability to enhance the intensity of light emitted by individual quantum dots by up to 20 times. The precision method for making the light-emitting particle clusters will greatly advance scientists' ability to study and modify the optical properties of quantum dots, and could eventually lead to improved solar energy conversion devices, light-controlled electronics, and biosensors.

Using chemical "nanoblasts" that punch tiny holes in the protective membranes of cells, researchers have demonstrated a new technique for getting therapeutic small molecules, proteins and DNA directly into living cells.

Numerous pathogens can cause bloodstream infections (sepsis) and the most straightforward cure is to remove the disease-causing factors from a patient's blood as quickly as possible. By using metal nanomagnets carrying target-specific ligands, researchers at ETH Zurich have shown that blood purification at a nano- to pico-molar scale is possible.

Researchers report the creation of pseudo-magnetic fields far stronger than the strongest magnetic fields ever sustained in a laboratory – just by putting the right kind of strain onto a patch of graphene. They show that when graphene is stretched to form nanobubbles on a platinum substrate, electrons behave as if they were subject to magnetic fields in excess of 300 tesla, even though no magnetic field has actually been applied.

 graphene nanobubble

In this scanning tunneling microscopy image of a graphene nanobubble, the hexagonal two-dimensional graphene crystal is seen distorted and stretched along three main axes.

Friday, July 23, 2010

This week in nanotechnology - July 23, 2010

Nanotechnologists at University of Twente's MESA+ research institute have developed a sensor that can detect anthrax spores. The invention is more sensitive and efficient than existing detection methods. The sensor that can detect a biomarker of the spores and thus determine their presence in a concentration one thousand times lower than the known toxic level.

Gene-silencing nanoparticles may put end to mosquito pest. Research conducted by a Kansas State University team may help solve a problem that scientists and pest controllers have been itching to for years. The team investigated using nanoparticles to deliver double-stranded ribonucleic acid, dsRNA – a molecule capable of specifically triggering gene silencing – into mosquito larvae through their food. By silencing particular genes, the dsRNA may kill the developing mosquitoes or make them more susceptible to pesticides.

A new vaccine-delivery patch based on hundreds of microscopic needles that dissolve into the skin could allow persons without medical training to painlessly administer vaccines -- while providing improved immunization against diseases such as influenza. Patches containing micron-scale needles that carry vaccine with them as they dissolve into the skin could simplify immunization programs by eliminating the use of hypodermic needles – and their "sharps" disposal and re-use concerns. Applied easily to the skin, the microneedle patches could allow self-administration of vaccine during pandemics and simplify large-scale immunization programs in developing nations.

vaccine-delivery patch

By imaging the cell walls of a zinnia leaf down to the nanometer scale, energy researchers have a better idea about how to turn plants into biofuels. Using different microscopy methods, the team was able to visualize single cells in detail, cellular substructures, fine-scale organization of the cell wall, and even chemical composition of single zinnia cells, indicating that they contain an abundance of lignocellulose.

To trap and hold tiny microparticles, engineers at Harvard have "put a ring on it," using a silicon-based circular resonator to confine particles stably for up to several minutes. The advance could one day lead to the ability to direct, deliver, and store nanoparticles and biomolecules on all-optical chips.

Scientists at the University of Liverpool have constructed molecular 'knots' with dimensions of around two nanometer. Most molecules are held together by chemical bonds between atoms – 'nano-knots' are instead mechanically bonded by interpenetrating loops. This is an unusual example of 'self-assembly', a process which underpins biology and allows complex structures to assemble from more simple building blocks.

The molecular knots have dimensions of around two nanometers

ETH Zurich researchers have built a transistor whose crucial element is a carbon nanotube, suspended between two contacts, with outstanding electronic properties. A novel fabrication approach allowed the scientists to construct a transistor with no gate hysteresis. This opens up new ways to manufacture nano-sensors and components that consume particularly little energy.

Engineers at Oregon State University have made a significant advance toward producing electricity from sewage, by the use of new coatings on the anodes of microbial electrochemical cells that increased the electricity production about 20 times. The findings bring the researchers one step closer to technology that could clean biowaste at the same time it produces useful levels of electricity – a promising new innovation in wastewater treatment and renewable energy.

Astronomers using NASA's Spitzer Space Telescope have discovered carbon molecules, known as "buckyballs," in space for the first time. The fukkerenes were found in a planetary nebula named Tc 1. Planetary nebulas are the remains of stars, like the sun, that shed their outer layers of gas and dust as they age. A compact, hot star, or white dwarf, at the center of the nebula illuminates and heats these clouds of material that has been shed. The buckyballs were found in these clouds, perhaps reflecting a short stage in the star's life, when it sloughs off a puff of material rich in carbon.

Friday, July 16, 2010

This week in nanotechnology - July 16, 2010

Nanotechnology wound dressing automatically detects and treats infection. Researchers in the UK have conducted experiments that explored the elementary question of what it is that makes some bacteria pathogenic, and some not? Based on their findings, they have demonstrated that a simple vesicle (nanocapsule) system can be used as a 'nano-Trojan horse' for controlling bacterial growth and infection. Integrated into wound dressings, this novel material can automatically detect infection by pathogenic bacteria and respond to this by releasing an antibiotic into the wound, and changing color to alert medical staff.

A team of researchers from Delft University of Technology announces a new type of nanopore device that may significantly impact the way we screen DNA molecules, for example to read off their sequence. They report a novel technique to fabricate tiny holes in a layer of graphene (a carbon layer with a thickness of only 1 atom) and they managed to detect the motion of individual DNA molecules that travel through such a hole.

Adding a bit of graphene to battery materials could dramatically cut the time it takes to recharge electronics. Researchers at the Department of Energy's Pacific Northwest National Laboratory have demonstrated that small quantities of graphene — an ultra-thin sheet of carbon atoms — can dramatically improve the power and cycling stability of lithium-ion batteries, while maintaining high energy storage capacity. The pioneering work could lead to the development of batteries that store larger amounts of energy and recharge quickly.

New solar-powered process removes CO2 from the air and stores it as solid carbon. Researchers have now presented the first experimental evidence of a new solar conversion process, combining electronic and chemical pathways, for carbon dioxide capture in what could become a revolutionary approach to remove and recycle CO2 from the atmosphere on a large scale. Rather than trying to sequester or hide away excess carbon dioxide, this new method allows it to be stored as solid carbon or converted in useful products ranging from plastics to synthetic jet fuel.

Rice University scientists have found the "ultimate" solvent for all kinds of carbon nanotubes, a breakthrough that brings the creation of a highly conductive quantum nanowire ever closer. Nanotubes have the frustrating habit of bundling, making them less useful than when they're separated in a solution. The researchers have found that chlorosulfonic acid can dissolve half-millimeter-long nanotubes in solution, a critical step in spinning fibers from ultralong nanotubes.

New research confirms that a revolutionary technology developed at Wake Forest University will slash years off the time it takes to develop drugs – bringing vital new treatments to patients much more quickly. Lab-on-Bead uses nanoscopic beads studded with "pins" that match a drug to a disease marker in a single step, so researchers can test an infinite number of possibilities for treatments all at once. When Lab-on-Bead makes a match, it has found a viable treatment for a specific disease – speeding up drug discovery by as much as 10,000 times and cutting out years of testing and re-testing in the laboratory.

Friday, July 9, 2010

This week in nanotechnology - July 9, 2010

Clusters of heated, magnetic nanoparticles targeted to cell membranes can remotely control ion channels, neurons and even animal behavior. The UB researchers demonstrated that their method could open calcium ion channels, activate neurons in cell culture and even manipulate the movements of the tiny nematode, C. elegans.

While those wonderful light sabers in the Star Wars films remain the figment of George Lucas' fertile imagination, light mills – rotary motors driven by light – that can power objects thousands of times greater in size are now fact. Researchers have created the first nano-sized light mill motor whose rotational speed and direction can be controlled by tuning the frequency of the incident light waves.

Researchers have demonstrated how they can adjust process conditions to influence the properties of novel plasma polymer coatings containing silver nanoparticles. Tailor-made films can be generated through a one-step plasma process. The scientists developed these new coatings, which kill bacteria while having no negative effect on human tissue.

At first, nanoshocks may seem like something to describe the millions of aftershocks of a large earthquake. But physicists are using an ultra-fast laser-based technique they dubbed "nanoshocks" for something entirely different. In fact, the "nanoshocks" have such a small spatial scale that scientists can use them to study shock behavior in tiny samples such as thin films or other systems with microscopic dimensions (a few tens of micrometers). In particular they have used the technique to shock materials under high static pressure in a diamond anvil cell.

Researchers are using nanotechnology to develop a medical dressing which will detect and treat infection in wounds. The dressing will work by releasing antibiotics from nanocapsules triggered by the presence of disease-causing pathogenic bacteria, which will target treatment before the infection takes hold. The dressing will also change colour when the antibiotic is released, alerting healthcare professionals that there is infection in the wound.

The tunable fluorescent nanoparticles known as quantum dots make ideal tools for distinguishing and identifying rare cancer cells in tissue biopsies. New research describes how multicolor quantum dots linked to antibodies can distinguish the Reed-Sternberg cells that are characteristic of Hodgkin's lymphoma.

Reed-Sternberg cells

Reed-Sternberg cells can be distinguished by their red outline, blue and white internal staining, and their lack of green staining

Metallic carbon nanotubes show great promise for applications from microelectronics to power lines because of their ballistic transmission of electrons. But who knew magnets could stop those electrons in their tracks? Researchers came to the unexpected conclusion that magnetic fields can turn highly conductive nanotubes into semiconductors.

Biomechanical energy is one of the main energy components in biological systems. Developing an effective technique that can convert biomechanical energy into electricity is important for the future of in vivo implantable biosensors and other nanomedical devices. Researchers have already shown the conversion of biomechanical energy into electricity by a muscle-movement-driven nanogenerator to harvest mechanical energy from body movement under in vitro conditions. In a first demonstration of using nanotechnology to convert tiny physical motion into electricity in an in vivo environment, the same team has now reported the implanting of a nanogenerator in a live rat to harvest energy generated by its breath and heartbeat.