June 19, 2009: Russia’s state-owned nanotech business group RUSNANO and Japan’s Ministry of Economy, Trade and Industry (METI) have agreed to establish a “workgroup” to collaborate in nanotechnology, initially to select Japanese nanotech application projects that can be implemented in Russia, according to the according to a statement.

The agreement — announced as RUSNANO officials tour Japan to study the nation’s support for its nanotech industry and innovation, seeking “best practices” will focus on selecting specific projects the two can work on together. Companies being visited on this tour include Hitachi, Toshiba, and Sumitomo, as well as Nippon Keidanren (the Japanese Business Federation) and the city of Tsukuba, seen as a nanotech R&D hub. Alexander Losyukov, RUSNANO deputy director general (and former Russian ambassador to Japan), will spearhead things from the Russian side; Japan’s participation will be helmed by Hideiti Okada, director general of METI’s trade policy department.

Further discussions will involve how to expand the cooperation to include smaller businesses alongside larger ones. The two also are eyeing a follow-up “platform for dialogue,” possibly to coincide with the Nanotechnology International Forum in Moscow scheduled for October.

June 18, 2009: Researchers from IBM and the U. of Regensburg (Germany) say they have demonstrated the ability to measure the charge state of a single atom, distinguishing between neutral/positive/negative ones, using noncontact atomic force microscopy (AFM) — an achievement they say opens up explorations into nanoscale structures and devices “at the ultimate atomic and molecular limits” for applications in molecular electronics, catalysis, and photovoltaics.

The work, reported in the June 12 issue of Science, imaged and identified differently charged gold and silver atoms by measuring the differences in forces between the AFM tip and charged/uncharged atoms located below it. The tool setup is a combined scanning tunneling microscope (STM) and atomic force microscope (AFM) operated in vacuum at very low temperature (5 Kelvin). The AFM incorporates a qPlus force sensor with a tip mounted on one prong of a tuning fork (the other prong is fixed), which actuates mechanically with ≤0.02nm oscillation amplitudes. As the AFM tip approaches the sample, the tuning fork’s resonance frequency shifts; scanning the tip over the surface and measuring the differences in frequency shift creates a force map of the surface; measuring the variation of force with voltage applied between tip and sample allowed them to distinguish between positively and negatively charged single atoms. The researchers found the difference in forces between a neutral gold atom and one with an additional electron was about 11piconewtons (accurate to <1piconewton), measured about half a nanometer above the atom.

Figure 1: Single atoms (orange) could be connected with molecules to form metal-molecular networks. Using the tip for charging these atoms, scientists could then inject electrons into the system and measure their distribution directly with the non-contact AFM. Understanding the charge distribution in molecules and molecular networks is a crucial step in the exploration of future computing elements on the nanoscale. (Source: IBM)

“The AFM with single-electron-charge sensitivity is a powerful tool to explore the charge transfer in molecule complexes, providing us with crucial insights and new physics to what might one day lead to revolutionary computing devices and concepts,” explains Gerhard Meyer, who leads the STM and AFM-related research efforts at IBM’s Zurich Research Laboratory. To study the charge transfer in molecule complexes, scientists envision that, in future experiments, single atoms could be connected with molecules to form metal-molecular networks (see Figure 1). Using the tip for charging these atoms, scientists could then inject electrons into the system and measure their distribution directly with the non-contact AFM (see Figure 2).

Figure 2: Model of the experimental setup (left). The gold atom is on a substrate covered with a very thin insulating film of sodium chloride, which also stabilizes the charged atom. The atomically-sharp AFM tip is brought into close proximity with the gold atom, up to a minimum distance of about 0.5nm. The tip, which is mounted on one prong of a tuning fork (not shown) oscillates with amplitudes as small as 0.02nm, about one-tenth of an atom’s diameter. Using this setup, the scientists were able to sense the minute differences in the force exerted by a neutral gold atom and a gold atom charged with one additional electron (right). (Source: IBM)

June 18, 2009: Researchers at the U. of California-Riverside and Seoul National University have fabricated microscopic polymer beads that change color according to changes in magnetic fields, touting their possible use in reusable signs, magnetically activated security features, and environmentally friendly pigments.

The “magnetochromatic microspheres” are said to be compatible with dispersion media including water, alcohol, hexane, and even polymer solutions, able to retain magnetically tunable colors in various chemical environments. They have “excellent structural stability” with the color change not affecting their structure or intrinsic properties, according to UC-Riverside’s Yadong Yin, assistant professor of chemistry.

Their work appeared in the June 15 online issue of the Journal of the American Chemical Society.

In the lab, researchers mixed magnetic iron oxide particles into a resin (a liquid that solidifies on exposure to UV-curable resin), and dispersed the resin in oil where it transformed into spherical droplets. An external magnetic field was applied to organize the iron oxide particles into periodically orderedstructures , which display a reflective color if viewed along the direction of the magnetic field. Exposing the liquid system to UV radiation polymerized the resin droplets to make them solid microspheres. Changing the orientation of the array “switched” the colors on and off via interference effects, rather than pigmentation (think the color schemes seen in some birds, butterflies, and beetles). The color states are also bistable, which is required for rewritable displays.

“Conventional methods to produce tunable structural color rely on changing the periodicity of the array or the refractive index of the materials — changes that are difficult to achieve or involve slow processes,” said Yin in a statement. In the UC-R/Seoul method, the color is tuned by changing the relative orientation of the microspheres’ periodic arrays through stimulation of external magnetic fields — which, he added, “has the additional benefits of instant action, contactless control, and easy integration into electronic devices already in the market.”

The researchers next plan to further explore specific applications for the magnetochromatic microspheres. Candidates include rewritable energy-saving display units such as papers and posters; future work will target development of a similar material for chemical and biological sensors.

Optical microscopy images of magnetochromatic microspheres with different diffraction colors switched “on” by using external magnetic fields. (Image credit: Yin lab, UC Riverside.)

June 15, 2009: Researchers at New York University say they’ve created a method to precisely bind nanoparticles into larger structures that overcomes a “sticky” problem and enables creation of stable, sophisticated microscopic and macroscopic structures.

The work, reported in an advanced online publication by Nature Materials, describes confronting the problem of self-replication: when the number of objects doubles in each cycle it presents a linear challenge when trying to fabricate things microscopic objects with a sophisticated architecture.

Their solution? Coat micrometer particles with short stretches of DNA (“sticky ends”), each with a particular sequence of DNA building blocks; those with complimentary sequences form reversible bonds when a certain temperature is applied. Thus, the particles can be organized in a controlled fashion onto a template, and then released again.

The novel DNA ‘sticky ends’ can form intra-particle loops and hairpins (e.g. schemes II & III), giving more control over the particles’ interactions than conventional sticky ends that can only form inter-particle bridges (scheme Ia). (Source: NYU)

DNA-mediated interactions are known, but binding just subsets of a particle (not the whole thing) into structures has proven difficult. So the researchers at NYU’s Center for Soft Matter Research and in the university’s Department of Chemistry focused on a particular type of DNA sequence that can fold like a hairpin and bind to neighboring “sticky ends,” determining that lowering the temperature rapidly caused the sticky ends to fold up on the particle before they could bind to other sticky ends; this occurred long enough (a few minutes) for the sticky ends to find binding partners on other particles (moved around by optical traps), thus building a structure. “We can finely tune and even switch off the attractions between particles, rendering them inert unless they are heated or held together — like a nano-contact glue,” said Mirjam Leunissen, the study’s lead author, in a statement.

Potential applications listed by NYU include ordering arrays of these particles into optical devices such as sensors and photonic crystals. The same organizational principles also apply to smaller nanoparticles, which have a range of electrical, optical, and magnetic properties useful for applications, NYU noted.

The work was supported by the NSF’s Materials Research Science and Engineering Center (MRSEC) program, the Keck Foundation, and the Netherlands Organization for Scientific Research.

June 11, 2009: Scientists have identified for the first time a mechanism by which nanoparticles cause lung damage and have demonstrated that it can be combated by blocking the process involved, taking a step toward addressing the growing concerns over the safety of nanotechnology.

Although nanoparticles have been linked to lung damage, it has not been clear how they cause it.

In a study published online today in the newly launched Journal of Molecular Cell Biology, Chinese researchers discovered that a class of nanoparticles being widely developed in medicine – ployamidoamine dendrimers (PAMAMs) — cause lung damage by triggering a type of programmed cell death known as autophagic cell death. They also showed that using an autophagy inhibitor prevented the cell death and counteracted nanoparticle-induced lung damage in mice.

“This provides us with a promising lead for developing strategies to prevent lung damage caused by nanoparticles. Nanomedicine holds extraordinary promise, particularly for diseases such as cancer and viral infections, but safety concerns have recently attracted great attention and with the technology evolving rapidly, we need to start finding ways now to protect workers and consumers from any toxic effects that might come with it,” said the study’s leader, Chengyu Jiang, a molecular biologist at the Chinese Academy of Medical Sciences in Beijing, China.

The first nanomaterial was developed by German scientists in 1984. Nanomaterials are now used in a variety of products, including sporting goods, cosmetics and electronics. The fact that unusual physical, chemical, and biological properties can emerge in materials at the nanoscale makes them particularly appealing for medicine. Scientists hope nanoparticles will be able to improve the effectiveness of drugs and gene therapy by carrying them to the right place in the body and by targeting specific tissues, regulating the release of drugs and reducing damage to healthy tissues. They also envision the possibility of implantable nano devices that would detect disease, treat it and report to the doctor automatically from inside the body. The U.S. Food and Drug Administration has approved some first generation nanodrugs. One example is Abraxane, a nanoformulation of the anti-cancer chemotherapy paclitaxel.

Lung damage is the chief human toxicity concern surrounding nanotechnology, with studies showing that most nanoparticles migrate to the lungs. However, there are also worries over the potential for damage to other organs.

In the study, the researchers first showed, through several independent experiments, that several types of PAMAMs killed human lung cells in the lab. They did not observe any evidence that the cells were dying by apoptosis, a common type of programmed cell death. However, they found that the particles triggered autophagic cell death through the Akt-TSC2-mTOR signalling pathway. Autophagy is a process that degrades damaged materials in a cell and plays a normal part in cell growth and renewal, but scientists have found that sometimes an overactivity of this destruction process leads to cell death.

Top: Percentage of cells containing autophagic vesicles after treatment with control, PAMAM G5.5, PAMAM G3 ,and PAMAM G3 plus 3MA. Bottom: Percentage of cells tested positive for light chain 3 (LC3) — a marker protein for autophagy — after control, PAMAM G5.5, PAMAM G3, and PAMAM G3 plus 3MA treatment. [**P < 0.01 and *P < 0.05.] (Source: Journal of Molecular Cell Biology)

The researchers also found that treating the cells with an autophagy inhibitor known as 3MA significantly inhibited the process, increasing the number of cells that survived exposure to the nanoparticles.

“Those results, taken together, showed that autophagy plays a critical role in the nanoparticle-induced cell death,” said Jiang.

The scientists then tested their findings in mice. They found that introducing the toxic nanoparticles significantly increased lung inflammation and death rates in the mice, but injecting the mice with the autophagy inhibitor 3MA before introducing the nanoparticles significantly ameliorated the lung damage and improved survival rates.

“These experiments indicate that autophagy is indeed involved in lung damage caused by these nanoparticles and that inhibition of this process might have therapeutic effects,” Jiang said. “We will likely need to look for additional new inhibitors to block lung damage as this particular compound is not stable in humans, but this gives us a promising lead for the first time.”

“Our study has identified the principle for developing such compounds. The idea is that, to increase the safety of nanomedicine, compounds could be developed that could either be incorporated into the nano product to protect against lung damage, or patients could be given pills to counteract the effects,” Jiang said, adding that the findings could also provide important insight into how nanopaticles cause other toxic effects.

It is not clear whether other types of nanoparticles would cause lung damage via the same mechanism, but some may, Jiang said. The group’s research also suggests that blocking autophagic cell death could perhaps be useful in combating other causes of lung damage.

June 10, 2009: The US Food and Drug Administration can regulate nanotechnology using its existing authority, but questions remain over the size of food ingredients, according to an FDA official.

Food Production Daily reports that Annette McCarthy, of the office of food additive safety at the FDA’s Center for Food Safety and Applied Nutrition, is warning that food ingredients on the nanoscale could change the “identity” and the toxicity of the ingredient.

“We believe that the regulatory authority is sufficient to address nanotechnology but there are further questions we need to address,” McCarthy said, speaking at the IFT International Food Nanoscience Conference in Anaheim.

She said that manufacturers looking to petition the FDA for acceptance of a nanotech food additive or coloring’s safety should examine its “impact on identity and toxicity.”

She also said the FDA is in the process of developing a guidance document for nanotechnology, scheduled to be available before the end of 2010.

April 30, 2009: With more than $40 billion in government funds having been poured into nanotechnology research worldwide over the last five years, countries are now emphasizing the importance of application-driven research in this emerging field while a shakeup is occurring among the leading nations in nanotech spending, according to a new white paper from London-based Cientifica Ltd.

Cientifica, a consulting firm in emerging technologies, in its yearly analysis of government funding figures is reporting in a free white paper “Nanotechnology Takes a Deep breath, and Prepares to Save the World!” that governments will be spending nearly $10 billion on nanotechnology research in 2009, but despite this huge figure government spending has begun to slow down. Spending will only grow by 9.3 percent from 2008-2012 compared with the 130% increase witnessed from 2004-2008.

With this slowdown, governments are urging more emphasis on application-driven research that will help individual countries meet their particular grand challenges whether it is energy independence or clean drinking water.

Cientifica’s research has also reveals that the long-time leaders of nanotechnology funding, the US and Japan, have now fallen to third and fourth behind the EU and Russia, with the US being tied with China for third.