Friday, February 25, 2011

This week in nanotechnology - February 25, 2011

For the first time, scientists have managed to measure the atomic structure of individual nanoparticles. The experimental data could help better understand the properties of nanoparticles in future. The exact 3D morphology, atomic structure and especially the surface composition of nanoparticles govern their chemical and physical properties. In a study, the three-dimensional structure of individual nanoparticles has now successfully been determined on the atomic level.

New nanomaterials research from the University at Buffalo could lead to new solutions for an age-old public health problem: how to separate bacteria from drinking water. Working with a special kind of polymer called a block copolymer, a research team has synthesized a new kind of nanomembrane containing pores about 55 nanometers in diameter -- large enough for water to slip through easily, but too small for bacteria.

For the first time, a team of scientists have succeeded in combining the concepts of spin electronics and molecular electronics in a single component consisting of a single molecule. Components based on this principle have a special potential, as they allow for the production of very small and highly efficient magnetic field sensors for read heads in hard disks or for non-volatile memories in order to further increase reading speed and data density.
Scanning tunneling microscopy  of organic molecules
Scanning tunneling microscopy (50 x 50 nm2) of organic molecules. Coloring indicates variable spin orientation.

MIT engineers have designed a new type of nanoparticle that could safely and effectively deliver vaccines for diseases such as HIV and malaria. The new particles consist of concentric fatty spheres that can carry synthetic versions of proteins normally produced by viruses. These synthetic particles elicit a strong immune response — comparable to that produced by live virus vaccines — but should be much safer.

Researchers have developed a simple method of making short protein chains with spiral structures that can also dissolve in water, two desirable traits not often found together. Such structures could have applications as building blocks for self-assembling nanostructures and as agents for drug and gene delivery.

Vaccine scientists say their "Holy Grail" is to stimulate immunity that lasts for a lifetime. Live viral vaccines such as the smallpox or yellow fever vaccines provide immune protection that lasts several decades, but despite their success, scientists have remained in the dark as to how they induce such long lasting immunity. Scientists now have designed nanoparticles that resemble viruses in size and immunological composition and that induce lifelong immunity in mice. They designed the particles to mimic the immune-stimulating effects of one of the most successful vaccines ever developed – the yellow fever vaccine. The particles, made of biodegradable polymers, have components that activate two different parts of the innate immune system and can be used interchangeablywith material from many different bacteria or viruses.

Friday, February 18, 2011

This week in nanotechnology - February 18, 2011

Researchers have documented the first observations of some unusual physics when two prominent electric materials are connected: superconductors and graphene. When a current is applied to a normal conductor, such as metal or graphene, it flows through the material as a stream of single electrons. By contrast, electrons travel in pairs in superconductors. Yet when a normal material is sandwiched between superconductors, the normal metal can carry the supercurrent.

From the art world: Nanoscopic investigation shows why van Gogh paintings lose their shine. cientists have identified a complex chemical reaction responsible for the degradation of two paintings by Vincent van Gogh and other artists of the late 19th century. This discovery is a first step to understanding how to stop the bright yellow colours of van Gogh's most famous paintings from being covered by a brown shade, and fading over time. In the meantime, the results suggest shielding affected paintings as much as possible from UV and sunlight.
how X-Rays were used to study why van Gogh paintings lose their shine
This illustration shows how X-Rays were used to study why van Gogh paintings lose their shine. Top: a photo of the painting "Bank of the River Seine" on display at the van Gogh Museum, divided in three and artificially colored to simulate a possible state in 1887 and 2050. Bottom left: microscopic samples from art masterpieces moulded in plexiglass blocks. The tube with yellow chrome paint is from the personal collection of M. Cotte. Bottom right: X-ray microscope set-up at the ESRF with a sample block ready for a scan. Centre: an image made using a high-resolution, analytical electron microscope to show affected pigment grains from the van Gogh painting, and how the color at their surface has changed due to reduction of chromium.


Scientists have invented a new way of creating atom thin nano-sheets from a wide variety of exotic layered materials with the potential to enable the next generation of electronic and energy storage technologies needed, for example, to power electric cars.

Engineering atomic interfaces for new electronics: A multi-institutional team has made fundamental discoveries at the border regions, called interfaces, between oxide materials. The team has discovered how to manipulate electrons oxide interfaces by inserting a single layer of atoms. The researchers also have discovered unusual electron behaviors at these engineered interfaces.

And finally, some Friday fun: Geckoman! Video game introduces youths to big ideas about a nano-sized world. Working on a science fair project with his lab partner Nikki, Harold Biggums finds himself transformed into a tiny superhero and flung into the midst of an alien plot to take over the world — a plot that he and Nikki can foil only by defying gravity, walking on water and charging across electric fields. This narrative dilemma is the basic storyline for Geckoman! - A video game about nanoscale forces, an online video game developed by Northeastern University researchers at the Center for High-rate Nanomanufacturing (CHN), which seeks to educate middle-school students about nanoscience and technology.

Friday, February 11, 2011

This week in nanotechnology - February 11, 2011

Engineers and scientists collaborating at Harvard University and the MITRE Corporation have developed and demonstrated the world's first programmable nanoprocessor. The groundbreaking prototype computer system represents a significant step forward in the complexity of computer circuits that can be assembled from synthesized nanometer-scale components.

In a complex feat of nanoengineering, a team of scientists at Kyoto University and the University of Oxford have succeeded in creating a programable molecular transport system, the workings of which can be observed in real time. The results open the door to the development of advanced drug delivery methods and molecular manufacturing systems.

Engineers at the University of California, Berkeley, have found a way to grow nanolasers directly onto a silicon surface, an achievement that could lead to a new class of faster, more efficient microprocessors, as well as to powerful biochemical sensors that use optoelectronic chips. Ultimately, this technique may provide a powerful and new avenue for engineering on-chip nanophotonic devices such as lasers, photodetectors, modulators and solar cells.

It has been a dream of researchers for over a decade: image biological materials at high resolution using incredibly intense X-ray laser pulses. Calculations had long predicted that these blasts of X-rays would allow exquisite measurements of the molecular structure of biological objects, from samples too small to be studied by conventional methods. Now, an international collaboration has proven this principle at the Linac Coherent Light Source (at SLAC National Accelerator Laboratory in California, USA) by forming images of the Photosystem I protein complex and particles of the Mimivirus. The results open a way for obtaining the molecular structures of proteins and viruses without the requirement of high-quality crystals.
Three-dimensional rendering of X-ray diffraction data obtained from over 15 000 single nanocrystal diffraction snapshots
Three-dimensional rendering of X-ray diffraction data obtained from over 15 000 single nanocrystal diffraction snapshots.

Researchers from from Nagoya University in Japan and Aalto University in Finland along with their colleagues have developed a simple and fast process to manufacture high quality carbon nanotube-based thin film transistors on a plastic substrate. They used this technology to manufacture the world's first sequential logic circuits using carbon nanotubes. Using this technology, we can expect the development of high-speed roll-to-roll manufacturing processes to manufacture low cost flexible devices such as electronic paper in the future.

A new combination of nanoparticles and graphene results in a more durable catalytic material for fuel cells. The catalytic material is not only hardier but more chemically active as well. The researchers are confident the results will help improve fuel cell design. The unique structure of this material provides much needed stability, good electrical conductivity and other desired properties.

Friday, February 4, 2011

This week in nanotechnology - February 4, 2011

Windshields that shed water so effectively that they don't need wipers. Ship hulls so slippery that they glide through the water more efficiently than ordinary hulls. These are some of the potential applications for graphene, one of the hottest new materials in the field of nanotechnology. Researchers have now figured out how to create a freestanding film of graphene oxide and alter its surface roughness so that it either causes water to bead up and run off or causes it to spread out in a thin layer.

Researchers from the University of Alabama at Birmingham's School of Engineering have created a three-dimensional electrospun scaffold on the nanoscale that more effectively and efficiently facilitates cell and tissue growth in the laboratory.

Using a concept called DNA origami, Arizona State University researchers are trying to pave the way to produce the next generations of electronics products. They have discovered a way to use DNA to effectively combine top-down lithography with chemical bonding involving bottom-up self-assembly. Enabling various molecules to attach to the DNA produces smaller nanostructure configurations – thus opening the way to construction of smaller electronic device components.
DNA origami nanotubes
DNA origami nanotubes can be efficiently aligned between gold islands with various interisland distances and relative locations. This development represents progress toward the goal of bridging bottom-up and top-down assembly approaches.

A new type of thin solar cell based on a honeycomb pattern of nanoscale dimples could offer a new direction for the field. Researchers at Stanford University succeeded in harnessing plasmonics to more effectively trap light within thin solar cells to improve performance and push them one step closer to daily reality.

University of Maryland researchers have made a breakthrough in the use of visible light for making tiny integrated circuits. They introduced a technique called RAPID lithography that makes it possible to use visible light to attain lithographic resolution comparable to (and potentially even better than) that obtained with shorter wave length radiation. Though their advance is probably at least a decade from commercial use, they say it could one day make it possible for companies like Intel to continue their decades long tread of making ever smaller, faster, and cheaper computer chips.

For almost two decades, cardiologists have searched for ways to see dangerous blood clots before they cause heart attacks. Now, researchers at Washington University School of Medicine in St. Louis report that they have designed nanoparticles that find clots and make them visible to a new kind of X-ray technology. These nanoparticles will take the guesswork out of deciding whether a person coming to the hospital with chest pain is actually having a heart attack.