Friday, January 29, 2010

This week in nanotechnology - January 29, 2010

Heatable paint for aircraft: Scientists at Battelle have worked for nearly a decade to overcome ice buildup on aircraft. Recently, they developed an environmentally friendly deicing fluid that can be sprayed on planes prior to flight. Now those same scientists have created a technology using carbon nanotubes that will work to prevent ice from forming during in-flight applications that could change the way this problem is solved in the future.

Researchers in the Electro-Optics Center (EOC) Materials Division at Penn State have produced 100 mm diameter graphene wafers, a key milestone in the development of graphene for next generation high-power, high-frequency electronic devices.

This graphene wafer contains more than 22,000 devices and test structures.

This graphene wafer contains more than 22,000 devices and test structures.

As the first group in the world, researchers from Chalmers will build up body parts using nanocellulose and the body's own cells. The researchers will build up a three-dimensional nanocellulose network that is an exact copy of the patient's healthy outer ear and construct an exact mirror image of the ear. It will have sufficient mechanical stability for it to be used as a bioreactor, which means that the patient's own cartilage and stem cells can be cultivated directly inside the body or on the patient, in this case on the head.

Scientists have great expectations that nanotechnologies will bring them closer to the goal of creating computer systems that can simulate and emulate the brain's abilities for sensation, perception, action, interaction and cognition while rivaling its low power consumption and compact size. Researchers in France have now developed a hybrid nanoparticle-organic transistor that can mimic the main functionalities of a synapse.

Power-generating rubber films developed by Princeton University engineers could harness natural body movements such as breathing and walking to power pacemakers, mobile phones and other electronic devices. The material, composed of ceramic nanoribbons embedded onto silicone rubber sheets, generates electricity when flexed and is highly efficient at converting mechanical energy to electrical energy.

Phase transitions -- changes of matter from one state to another without altering its chemical makeup -- are an important part of life in our three-dimensional world. Water falls to the ground as snow, melts to a liquid and eventually vaporizes back to the clouds to begin the cycle anew. Now a team of scientists has devised a new way to explore how such phase transitions function in less than three dimensions and at the level of just a few atoms. They hope the technique will be useful to test aspects of what until now has been purely theoretical physics, and they hope it also might have practical applications for sensing conditions at very tiny scales, such as in a cell membrane.

And finally a reference to an interesting conference where nanotechnology solutions certainly will find a role to play in coming up with answers to the "14 challenges the world must address to ensure the planet's survival".

Friday, January 22, 2010

This week in nanotechnology - January 22, 2010

Quite a few developments in nanomedicne this week. Nanoparticle-studded contact lenses may change the way diabetics monitor their glucose levels. These engineered nanoparticles react with glucose molecules found in tears – similar to those found in blood – causing a chemical reaction. When there is a variation in a person’s sugar level, the contact lenses respond by changing their color.

Another medical nanoparticle application has been reported by researchers at MIT and Harvard Medical School, who have built targeted nanoparticles that can cling to artery walls and slowly release medicine, an advance that potentially provides an alternative to drug-releasing stents in some patients with cardiovascular disease.

Scientists have demonstrated that a quantum dot based siRNA (small interfering RNA) approach selectively inhibits brain cancer cells. They showed that small double-stranded RNA molecules can sequence-specifically inhibit the expression of targeted genes that are associated with the development of cancer.

View into a vacuum chamber where attosecond light pulses are generated.

Targeted delivery of multifunctional siRNA-quantum dots (red) incubated in a co-culture of malignant tumor cells. (Scale bar = 50 µm)

Biophysicists have published the results of single-molecule experiments that bring a higher-resolution tool to the study of protein folding. How proteins arrive at the three-dimensional shapes that determine their essential functions – or cause grave diseases when folding goes wrong – is considered one of the most important and least understood questions in the biological and medical sciences

Big-name retailers like Tesco and Carrefour should help prepare consumers for innovations in the food sector, according to the top civil servant in the EU executive's directorate for health and consumer protection. Robert Madelin, director-general of the European Commission's DG Sanco, told a meeting of retailers that supermarkets needed to be upfront in explaining the risks and benefits of advances such as nanotechnology.

New research sheds light on how atoms arrange themselves into thin films. To make thin films for semiconductors in electronic devices, layers of atoms must be grown in neat, crystalline sheets. But while some materials grow smooth crystals, others tend to develop bumps and defects – a serious problem for thin-film manufacturing.

Saturday, January 16, 2010

This week in Nanotechnology - Jan 15, 2010

A strip of paper infused with carbon nanotubes can quickly and inexpensively detect a toxin produced by algae in drinking water. Engineers at the University of Michigan led the development of the new biosensor.

Another group of researchers is working to develop nanoscale optical fiber biosensor tests, or assays, for detection of bioterrorist agents. They coat an optical fiber with antibodies or DNA that will bind to antigens or DNA in the specimen. When this happens, the light that normally passes through the fiber will be decreased, indicating the presence of a biological agent.

Anyone delving deep into matter must reckon with the fact that the usual time scales cease to be valid in the tiny dimensions of molecules, atoms and electrons. Molecules react within femtoseconds (millionths of a billionth of a second). The motion of electrons in atoms is a thousand times faster still, lasting just a few attoseconds. Researchers in Munich are conducting research on these ultrafast processes by means of ultrashort light flashes.

View into a vacuum chamber where attosecond light pulses are generated.

View into a vacuum chamber where attosecond light pulses are generated.

In many biomedical applications, protein nanotubes present several advantages over nanospheres. First, nanotubes can possess different interior and exterior surfaces independently. It is therefore possible to construct a one-dimensional space interior for specific reactions and a biocompatible surface exterior that can be tailored to target specific tissues or to respond to particular stimuli. Second, nanotubes have open end terminals, which may be useful for delivery applications. Large quantities of guest molecules can be readily loaded and released without structural change. Researchers in Japan describe for the first time molecular capturing properties of protein nanotubes with a controllable affinity and size selectivity.

Building microscopic materials known as superlattices on the surface of gold may lead to a treasure for researchers interested in faster, smaller, and more energy efficient computing devices, say researchers at Missouri University of Science and Technology.

Researchers in China have developed a simple method for fabricating environmentally stable superhydrophilic wool fabrics. They applied silica sols to natural wool fibers to form an ultrathin layer on the surface of the fibers, increasing both the surface roughness and surface energy of the wool fabrics. That way, functionalized fabrics can be obtained by further modification of the surface of the wool fibers with bioactive agents or stimuli-responsive molecules.

Friday, January 8, 2010

This week in nanotechnology, Jan 8, 2010

With the passage of a molecule through the labyrinth of a chemical system being so critical to catalysis and other important chemical processes, computer simulations are frequently used to model potential molecule/labyrinth interactions. In the past, such simulations have been expensive and time-consuming to carry out, but now researchers have developed a new algorithm that should make future simulations easier and faster to compute, and yield much more accurate results.

To circumvent the limitations of conventional computers in tackling the problems of understanding and modeling the behavior of complex quantum systems, physicists have proposed using well-understood quantum systems called ‘quantum simulators’ (or ‘quantum emulators’) to emulate similar, but otherwise poorly understood, quantum systems.

Schematic diagrams of three types of quantum simulators

Schematic diagrams of three types of quantum simulators: atoms (red) held in place by an optical field (green; top left); ions (yellow) aligned using an electromagnetic field (top right); and superconducting circuits (bottom) (Image: RIKEN)

Scientists at the University of Glasgow have imaged the self-assembly of nanoparticles, unveiling the blueprint for building designer molecular machines atom-by-atom.

A new class of biodegradable nanosized particles that can easily slip through the body’s sticky and viscous mucus secretions to deliver a sustained-release medication cargo.

Researchers have for the first time observed a nanoscale symmetry hidden in solid state matter. They have measured the signatures of a symmetry showing the same attributes as the golden ratio famous from art and architecture.