Individual silver nanoparticles in solutions typically grow through single atom attachment, but when they reach a certain size they can link with other particles, according to a team which includes scientists at Pacific Northwest National Laboratory. This seemingly simple result has shifted a long-held scientific paradigm that did not consider kinetic models when explaining how nanoparticle ensembles formed.
By emitting photons from a quantum dot at the top of a micropyramid, researchers at Linköping Univ. in Sweden are creating a polarized light source for such things as energy-saving computer screens and wiretap-proof communications.
By letting DNA strands grow together with gold, scientists in Finland have developed a new concept for super-sensitive disease diagnostics. The method relies on growth of a DNA strand over a narrow gap between two electrodes in an electric circuit. The strand will only grow if a certain DNA molecule has bound to the surface of one electrode, which makes it possible to build diagnostic tests for detection of that specific DNA molecule.
More than 2,800 commercially available applications are now based on nanoparticles, but this influx of nanotechnology is not without risks, say researchers at Missouri Univ. of Science and Technology. They have been systematically studying the effects of transition metal oxide nanoparticles on human lung cells and have found that the nanoparticles’ toxicity to the cells increased as they moved right on the periodic table.
Silk and diamonds aren't just for ties and jewelry anymore. They're ingredients for a new kind of tiny glowing particle that could provide doctors and researchers with a novel technique for biological imaging and drug delivery. Just tens of nanometers across, the new particles are made of diamond, covered in silk and can be injected into living cells.
Transparent displays have a variety of potential applications. A number of technologies have been developed for such displays, but all have limitations. Now, researchers have come up with a new approach that can have significant advantages over existing systems, at least for certain kinds of applications: a wide viewing angle, simplicity of manufacture and potentially low cost and scalability.
Rice Univ. scientists have found they can control the bonds between atoms in a molecule. The molecule in question is carbon-60, also known as the buckminsterfullerene and the buckyball, discovered at Rice in 1985. The scientists found that it’s possible to soften the bonds between atoms by applying a voltage and running an electric current through a single buckyball.
Vaccines combat diseases and protect populations from outbreaks, but the life-saving technology leaves room for improvement. Vaccines usually are made en masse in centralized locations far removed from where they will be used. They are expensive to ship and keep refrigerated and they tend to have short shelf lives. However, Univ. of Washington engineers have developed hope for on-demand vaccines.
Developed by a team of researchers in Massachusetts and California, “nanotraps” are nanoparticles that act as viral traps using specific molecules found naturally within the human body. Initial testing on the treatments, which each use tiny, non-toxic particles that can be injected, inhaled, or eaten, has shown them to be effective and safe against a multitude of strains of disease.
Researchers have developed a technique for creating nanoparticles that carry two different cancer-killing drugs into the body and deliver those drugs to separate parts of the cancer cell where they will be most effective. The technique was developed by researchers at North Carolina State Univ. and the Univ. of North Carolina at Chapel Hill.
Molecules anchored to the surfaces of nanoparticles modify and even control many characteristics of the particles, including how they interact with cells or react to light. Taking advantage of advanced instrumental capabilities, researchers have built a specially designed experimental cell to successfully deduce the how molecules of carboxylic acid, a common organic acid found in nature, bind to ceria nanoparticle surfaces.
The Ulsan National Institute of Science and Technology in Korea has developed a new method for the mass production of boron/nitrogen co-doped graphene nanoplatelets, which could lead to the fabrication of a graphene-based field-effect transistor with semiconducting nature. This opens up opportunities for practical use in electronic devices.
Researchers have created a new type of molecular motor made of DNA and demonstrated its potential by using it to transport a nanoparticle along the length of a carbon nanotube. The design was inspired by natural biological motors that have evolved to perform specific tasks critical to the function of cells.
Medical diagnostics seeks to learn early on whether a serious disease is developing or what its course will be. In many cases, treacherous molecules are present only in trace amounts, however. Researchers in Germany have come up with a new method of detection which has allowed them to notice the presence of only 17 dye molecules. The highly sensitive method might one day be used to scan a tiny drop of blood for potential diseases.
The same tiny cellulose crystals that give trees and plants their high strength, light weight and resilience, have now been shown to have the stiffness of steel. Calculations using precise models based on the atomic structure of cellulose show the crystals have a stiffness of 206 gigapascals, which is comparable to steel.
Physicists in Germany have developed a “planet-satellite model” to precisely connect and arrange nanoparticles in 3-D structures. Inspired by the photosystems of plants and algae, these artificial nanoassemblies of DNA strands might in the future serve to collect and convert energy.
A research team in France has invented an adhesion method that creates a strong bond between two gels by spreading on their surface a solution containing nanoparticles. Until now, there was no entirely satisfactory method of obtaining adhesion between two gels or two biological tissues. The bond is resistant to water and uses no polymers or chemical reactions.
Univ. of Oregon chemists studying the structure of ligand-stabilized gold nanoparticles have captured fundamental new insights about their stability. The information, they say, could help to maintain a desired, integral property in nanoparticles used in electronic devices, where stability is important.
Oil and water don’t mix, as any chemist or cook knows. Tom Russell, a polymer scientist from the Univ. of Massachusetts who now holds a visiting faculty appointment with Lawrence Berkeley National Laboratory’s Materials Sciences Div., is using that chemical and culinary truth to change the natural spherical shape of liquid drops into ellipsoids, tubes and even fibrous structures similar in appearance to glass wool.
Humble aluminum’s plasmonic properties may make it far more valuable than gold and silver for certain applications, according to new research by Rice Univ. scientists. Because aluminum, as nanoparticles or nanostructures, displays optical resonances across a much broader region of the spectrum than either gold or silver, it may be a good candidate for harvesting solar energy and for other large-area optical devices and materials.
Chemical engineers at Rice Univ. have found a new catalyst that can rapidly break down nitrites, a common and harmful contaminant in drinking water that often results from overuse of agricultural fertilizers. Nitrites and their more abundant cousins, nitrates, are inorganic compounds that are often found in both groundwater and surface water. The compounds are a health hazard.
Cooling systems generally rely on water pumped through pipes to remove unwanted heat. Now, researchers at Massachusetts Institute of Technology and in Australia have found a way of enhancing heat transfer in such systems by using magnetic fields, a method that could prevent hotspots that can lead to system failures. The system could also be applied to cooling everything from electronic devices to advanced fusion reactors, they say.
Batteries that power electric cars have problems. They take a long time to charge. The charge doesn’t hold long enough to drive long distances. They don’t allow drivers to quickly accelerate. They are big and bulky. By creating nanoparticles with controlled shape, engineers in California believe smaller, more powerful and energy-efficient batteries for vehicles can be built.
Sometimes big change comes from small beginnings. That’s especially true in the research of Anatoly Frenkel, a prof. of physics at Yeshiva Univ., who is working to reinvent the way we use and produce energy by unlocking the potential of some of the world’s tiniest structures: nanoparticles.
Using the x-ray beams at the European Synchrotron Research Facility a research team has showed that the electrons absorbed and released by cerium dioxide nanoparticles during chemical reactions behave in a completely different way than previously thought. They show that the electrons are not bound to individual atoms but, like a cloud, distribute themselves over the whole nanoparticle, like an electron “sponge".