Tag Archives: Switzerland

Global overview of nano-enabled food and agriculture regulation

First off, this post features an open access paper summarizing global regulation of nanotechnology in agriculture and food production. From a Sept. 11, 2015 news item on Nanowerk,

An overview of regulatory solutions worldwide on the use of nanotechnology in food and feed production shows a differing approach: only the EU and Switzerland have nano-specific provisions incorporated in existing legislation, whereas other countries count on non-legally binding guidance and standards for industry. Collaboration among countries across the globe is required to share information and ensure protection for people and the environment, according to the paper …

A Sept. 11, 2015 European Commission Joint Research Centre press release (also on EurekAlert*), which originated the news item, summarizes the paper in more detail (Note: Links have been removed),

The paper “Regulatory aspects of nanotechnology in the agri/feed/food sector in EU and non-EU countries” reviews how potential risks or the safety of nanotechnology are managed in different countries around the world and recognises that this may have implication on the international market of nano-enabled agricultural and food products.

Nanotechnology offers substantial prospects for the development of innovative products and applications in many industrial sectors, including agricultural production, animal feed and treatment, food processing and food contact materials. While some applications are already marketed, many other nano-enabled products are currently under research and development, and may enter the market in the near future. Expected benefits of such products include increased efficacy of agrochemicals through nano-encapsulation, enhanced bioavailability of nutrients or more secure packaging material through microbial nanoparticles.

As with any other regulated product, applicants applying for market approval have to demonstrate the safe use of such new products without posing undue safety risks to the consumer and the environment. Some countries have been more active than others in examining the appropriateness of their regulatory frameworks for dealing with the safety of nanotechnologies. As a consequence, different approaches have been adopted in regulating nano-based products in the agri/feed/food sector.

The analysis shows that the EU along with Switzerland are the only ones which have introduced binding nanomaterial definitions and/or specific provisions for some nanotechnology applications. An example would be the EU labelling requirements for food ingredients in the form of ‘engineered nanomaterials’. Other regions in the world regulate nanomaterials more implicitly mainly by building on non-legally binding guidance and standards for industry.

The overview of existing legislation and guidances published as an open access article in the Journal Regulatory Toxicology and Pharmacology is based on information gathered by the JRC, RIKILT-Wageningen and the European Food Safety Agency (EFSA) through literature research and a dedicated survey.

Here’s a link to and a citation for the paper,

Regulatory aspects of nanotechnology in the agri/feed/food sector in EU and non-EU countries by Valeria Amenta, Karin Aschberger, , Maria Arena, Hans Bouwmeester, Filipa Botelho Moniz, Puck Brandhoff, Stefania Gottardo, Hans J.P. Marvin, Agnieszka Mech, Laia Quiros Pesudo, Hubert Rauscher, Reinhilde Schoonjans, Maria Vittoria Vettori, Stefan Weigel, Ruud J. Peters. Regulatory Toxicology and Pharmacology Volume 73, Issue 1, October 2015, Pages 463–476 doi:10.1016/j.yrtph.2015.06.016

This is the most inclusive overview I’ve seen yet. The authors cover Asian countries, South America, Africa, and the MIddle East, as well as, the usual suspects in Europe and North America.

Given I’m a Canadian blogger I feel obliged to include their summary of the Canadian situation (Note: Links have been removed),

4.2. Canada

The Canadian Food Inspection Agency (CFIA) and Public Health Agency of Canada (PHAC), who have recently joined the Health Portfolio of Health Canada, are responsible for food regulation in Canada. No specific regulation for nanotechnology-based food products is available but such products are regulated under the existing legislative and regulatory frameworks.11 In October 2011 Health Canada published a “Policy Statement on Health Canada’s Working Definition for Nanomaterials” (Health Canada, 2011), the document provides a (working) definition of NM which is focused, similarly to the US definition, on the nanoscale dimensions, or on the nanoscale properties/phenomena of the material (see Annex I). For what concerns general chemicals regulation in Canada, the New Substances (NS) program must ensure that new substances, including substances that are at the nano-scale (i.e. NMs), are assessed in order to determine their toxicological profile ( Environment Canada, 2014). The approach applied involves a pre-manufacture and pre-import notification and assessment process. In 2014, the New Substances program published a guidance aimed at increasing clarity on which NMs are subject to assessment in Canada ( Environment Canada, 2014).

Canadian and US regulatory agencies are working towards harmonising the regulatory approaches for NMs under the US-Canada Regulatory Cooperation Council (RCC) Nanotechnology Initiative.12 Canada and the US recently published a Joint Forward Plan where findings and lessons learnt from the RCC Nanotechnology Initiative are discussed (Canada–United States Regulatory Cooperation Council (RCC) 2014).

Based on their summary of the Canadian situation, with which I am familiar, they’ve done a good job of summarizing. Here are a few of the countries whose regulatory instruments have not been mentioned here before (Note: Links have been removed),

In Turkey a national or regional policy for the responsible development of nanotechnology is under development (OECD, 2013b). Nanotechnology is considered as a strategic technological field and at present 32 nanotechnology research centres are working in this field. Turkey participates as an observer in the EFSA Nano Network (Section 3.6) along with other EU candidate countries Former Yugoslav Republic of Macedonia, and Montenegro (EFSA, 2012). The Inventory and Control of Chemicals Regulation entered into force in Turkey in 2008, which represents a scale-down version of the REACH Regulation (Bergeson et al. 2010). Moreover, the Ministry of Environment and Urban Planning published a Turkish version of CLP Regulation (known as SEA in Turkish) to enter into force as of 1st June 2016 (Intertek).

The Russian legislation on food safety is based on regulatory documents such as the Sanitary Rules and Regulations (“SanPiN”), but also on national standards (known as “GOST”) and technical regulations (Office of Agricultural Affairs of the USDA, 2009). The Russian policy on nanotechnology in the industrial sector has been defined in some national programmes (e.g. Nanotechnology Industry Development Program) and a Russian Corporation of Nanotechnologies was established in 2007.15 As reported by FAO/WHO (FAO/WHO, 2013), 17 documents which deal with the risk assessment of NMs in the food sector were released within such federal programs. Safe reference levels on nanoparticles impact on the human body were developed and implemented in the sanitary regulation for the nanoforms of silver and titanium dioxide and, single wall carbon nanotubes (FAO/WHO, 2013).

Other countries included in this overview are Brazil, India, Japan, China, Malaysia, Iran, Thailand, Taiwan, Australia, New Zealand, US, South Africa, South Korea, Switzerland, and the countries of the European Union.

*EurekAlert link added Sept. 14, 2015.

Natural nanoparticles and perfluorinated compounds in soil

The claim in a Sept. 9, 2015 news item on Nanowerk is that ‘natural’ nanoparticles are being used to remove perfluorinated compounds (PFC) from soil,

Perfluorinated compounds (PFC) are a new type of pollutants found in contaminated soils from industrial sites, airports and other sites worldwide.

In Norway, The Environment Agency has published a plan to eliminate PFOS [perfluorooctanesulfonic acid or perfluorooctane sulfonate] from the environment by 2020. In other countries such as China and the United States, the levels are far higher, and several studies show accumulation of PFOS in fish and animals, however no concrete measures have been taken.

The Norwegian company, Fjordforsk AS, which specializes in nanosciences and environmental methods, has developed a method to remove PFOS from soil by binding them to natural minerals. This method can be used to extract PFOS from contaminated soil and prevent leakage of PFOS to the groundwater.

Electron microscopy images show that the minerals have the ability to bind PFOS on the surface of the natural nanoparticles. [emphasis mine] The proprietary method does not contaminate the treated grounds with chemicals or other parts from remediation process and uses only natural components.

Electron microscopy images and more detail can be found in the Nanowerk news item.

I can’t find the press release, which originated the news item but there is a little additional information about Fjoorkforsk’s remediation efforts on the company’s “Purification of perfluorinated compounds from soil samples” project page,

Project duration: 2014 –

Project leader: Manzetti S.

Collaborators: Prof Lutz Ahrens. Swedish Agricultural University. Prof David van der Spoel, Uppsala University.

Project description:

Perfluorinated compounds (PFCs) are emerging pollutants used in flame retardants on a large scale on airports and other sites of heavy industrial activity. Perfluroinated compounds are toxic and represent an ultra-persistent class of chemicals which can accumulate in animals and humans and have been found to remain in the body for over 5 years after uptake. Perfluorinated compounds can also affect the nerve-system and have recently been associated with high- priority pollutants to be discontinued and to be removed from the environment. Using non-toxic methods, this project develops an approach to sediment perfluorinated compounds from contaminated soil samples using nanoparticles, in order to remove the ecotoxic and ground-water contaminating potential of PFCs from afflicted sites and environments.

The only mineral that I know is used for soil remediation is nano zero-valent iron (nZVI). A very fast search for more information yielded a 2010 EMPA [Swiss Federal Laboratories for Materials Science and Technology] report titled “Nano zero valent iron – THE solution for water and soil remediation? ” (32 pp. pdf) published by ObservatoryNANO.

As for the claim that the company is using ‘natural’ nanoparticles for their remediation efforts, it’s not clear what they mean by that. I suspect they’re using the term ‘natural’ to mean that engineered nanoparticles are being derived from a naturally occurring material, e.g. iron.

People for the Ethical Treatment of Animals (PETA) and a grant for in vitro nanotoxicity testing

This grant seems to have gotten its start at a workshop held at the US Environmental Protection Agency (EPA) in Washington, D.C., Feb. 24-25, 2015 as per this webpage on the People for Ethical Treatment of Animals (PETA) International Science Consortium Limited website,

The invitation-only workshop included experts from different sectors (government, industry, academia and NGO) and disciplines (in vitro and in vivo inhalation studies of NMs, fibrosis, dosimetry, fluidic models, aerosol engineering, and regulatory assessment). It focused on the technical details for the development and preliminary assessment of the relevance and reliability of an in vitro test to predict the development of pulmonary fibrosis in cells co-cultured at the air-liquid interface following exposure to aerosolized multi-walled carbon nanotubes (MWCNTs). During the workshop, experts made recommendations on cell types, exposure systems, endpoints and dosimetry considerations required to develop the in vitro model for hazard identification of MWCNTs.

The method is intended to be included in a non-animal test battery to reduce and eventually replace the use of animals in studies to assess the inhalation toxicity of engineered NMs. The long-term vision is to develop a battery of in silico and in vitro assays that can be used in an integrated testing strategy, providing comprehensive information on biological endpoints relevant to inhalation exposure to NMs which could be used in the hazard ranking of substances in the risk assessment process.

A September 1, 2015 news item on Azonano provides an update,

The PETA International Science Consortium Ltd. announced today the winners of a $200,000 award for the design of an in vitro test to predict the development of lung fibrosis in humans following exposure to nanomaterials, such as multi-walled carbon nanotubes.

Professor Dr. Barbara Rothen-Rutishauser of the Adolphe Merkle Institute at the University of Fribourg, Switzerland and Professor Dr. Vicki Stone of the School of Life Sciences at Heriot-Watt University, Edinburgh, U.K. will jointly develop the test method. Professor Rothen-Rutishauser co-chairs the BioNanomaterials research group at the Adolphe Merkle Institute, where her research is focused on the study of nanomaterial-cell interactions in the lung using three-dimensional cell models. Professor Vicki Stone is the Director of the Nano Safety Research Group at Heriot-Watt University and the Director of Toxicology for SAFENANO.

The Science Consortium is also funding MatTek Corporation for the development of a three-dimensional reconstructed primary human lung tissue model to be used in Professors Rothen-Rutishauser and Stone’s work. MatTek Corporation has extensive expertise in manufacturing human cell-based, organotypic in vitro models for use in regulatory and basic research applications. The work at MatTek will be led by Dr. Patrick Hayden, Vice President of Scientific Affairs, and Dr. Anna Maione, head of MatTek’s airway models research group.

I was curious about MatTek Corporation and found this on company’s About Us webpage,

MatTek Corporation was founded in 1985 by two chemical engineering professors from MIT. In 1991 the company leveraged its core polymer surface modification technology into the emerging tissue engineering market.

MatTek Corporation is at the forefront of tissue engineering and is a world leader in the production of innovative 3D reconstructed human tissue models. Our skin, ocular, and respiratory tissue models are used in regulatory toxicology (OECD, EU guidelines) and address toxicology and efficacy concerns throughout the cosmetics, chemical, pharmaceutical and household product industries.

EpiDerm™, MatTek’s first 3D human cell based in vitro model, was introduced in 1993 and became an immediate technical and commercial success.

I wish them good luck in their research on developing better ways to test toxicity.

Carrot-based helmets: a nanocellulose commercialization story

NanoCelluComp, a European Commission-funded project, whose name bears a close resemblance to a Scottish company, CelluComp, ended last year (my March 5, 2014 post). Both, NanoCelluComp and CelluComp, were/are involved in research featuring carrots and nanocellulose.

An Aug. 6, 2015 news item on ScienceDaily describes some Swiss/Scottish research into using carrot nanofibers in helmets,

Crackpot idea or recipe for success? This is a question entrepreneurs often face. Is it worth converting the production process to a new, ecologically better material? Empa [Swiss Federal Laboratories for Materials Science and Technology or Eidgenössische Materialprüfungs- und Forschungsansta] has developed an analysis method that enables companies to simulate possible scenarios — and therefore avoid bad investments. Here’s an example: Nanofibers made of carrot waste from the production of carrot juice, which can be used to reinforce synthetic parts.

All over the world, research is being conducted into biodegradable and recyclable synthetics. However, fiber-reinforced components remain problematic — if glass or carbon fibers are used. Within the scope of an EU research project, the Scottish company Cellucomp Limited has now developed a method to obtain nanofibers from carrot waste. [emphasis mine] These fibers would be both cost-effective and biodegradable. However, is the method, which works in the lab, also marketable on a large scale?

Here’s a composite image illustrating the notion of a carrot-based helmet,

Motorcycle helmets consist of fiber-reinforced synthetic material. Instead of glass fibers, a biological alternative is now also possible: plant fibers from the production of carrot juice. Empa researchers are now able to analyze whether this kind of production makes sense from an ecological and economical perspective – before money is actually invested in production plants.  Photo: 4ever.eu, composite photo: Empa

Motorcycle helmets consist of fiber-reinforced synthetic material. Instead of glass fibers, a biological alternative is now also possible: plant fibers from the production of carrot juice. Empa researchers are now able to analyze whether this kind of production makes sense from an ecological and economical perspective – before money is actually invested in production plants.
Photo: 4ever.eu, composite photo: Empa

An Aug. 6, 2015 Empa press release (also on EurekAlert), which originated the news item, provides more details abut the drive to commercialize this nanocellulose product,

An MPAS (multi-perspective application selection) method developed at Empa helps identify the industrial sectors where new materials might be useful from a technical and economical perspective. At the same time, MPAS also considers the ecological aspect of these new materials. The result for our example: Nanofibers made of carrot waste might be used in the production of motorcycle helmets or side walls for motorhomes in the future.

Three-step analysis

In order to clarify a new material’s market potential, Empa researchers Fabiano Piccinno, Roland Hischier and Claudia Som proceed in three steps for the MPAS method. First of all, the field of possible applications is defined: Which applications come into question based on the technical properties and what categories can they be divided into? Can the new material replace an existing one?

The second step concerns the technical feasibility and market potential: Can the material properties required be achieved with the technical process? Might the product quality vary from one production batch to the next? Can the lab process be upgraded to an industrial scale cost-effectively? Is the material more suited to the low-cost sector or expensive luxury goods? And finally: Does the product meet the legal standards and the customers’ certification needs?

In the third step, the ecological aspect is eventually examined: Is this new material for the products identified really more environmentally friendly – once all the steps from product creation to recycling have been factored in? Which factors particularly need to be considered during production stage to manufacture the material in as environmentally friendly a way as possible?

Industrial production on a five-ton scale – calculated theoretically

The MPAS approach enables individual scenarios for a future production to be calculated with an extremely high degree of accuracy. In the case of the carrot waste nanofibers, for instance, it is crucial whether five tons of fresh carrots or only 209 kilograms of carrot waste (fiber waste from the juicing process) are used as the base material for their production. The issue of whether the solvent is ultimately recycled or burned affects the production costs. And the energy balance depends on how the enzymes that loosen the fibers from the carrots are deactivated. In the lab, this takes place via heat; for production on an industrial level, the use of bleaching agents would be more cost-effective.

Conclusion: six possible applications for “carrot fibers“

For fiber production from carrot waste, the MPAS analysis identified six possible customer segments for the Scottish manufacturer Cellucomp that are worth taking a closer look at: Protective equipment and devices for recreational sport, special vehicles, furniture, luxury consumer goods and industrial manufacturing. The researchers listed the following examples: Motorcycle helmets and surfboards, side walls for motorhomes, dining tables, high-end loudspeaker boxes and product protection mats for marble-working businesses. Similarly detailed analyses can also be conducted for other renewable materials – before a lot of money is actually invested in production plants.

There are other attempts to commercialize nanocellulose (as I understand it, cellulose is one of the most common materials on earth and can be derived from several sources including trees, bananas, pineapples, and more) mentioned in my July 30, 2015 post. I will repeat a question from that post, where are the Canadian research efforts to develop and commercialize nanocellulose? If you have information, please do let me know.

Nano (?) diamonds used in mechanical system to control quantum states

We do end up back in the world of spin but, first, there are the nano (I think) diamonds in an Aug. 3, 2015 news item on Nanotechnology Now,

Scientists at the Swiss Nanoscience Institute at the University of Basel have used resonators made from single-crystalline diamonds to develop a novel device in which a quantum system is integrated into a mechanical oscillating system. For the first time, the researchers were able to show that this mechanical system can be used to coherently manipulate an electron spin embedded in the resonator – without external antennas or complex microelectronic structures. …

A July 16, 2014 University of Basel press release (also on EurekAlert), which originated the news item, provides more detail about the work,

In previous publications, the research team led by Georg H. Endress Professor Patrick Maletinsky described how resonators made from single-crystalline diamonds with individually embedded electrons are highly suited to addressing the spin of these electrons. These diamond resonators were modified in multiple instances so that a carbon atom from the diamond lattice was replaced with a nitrogen atom in their crystal lattices with a missing atom directly adjacent. In these “nitrogen-vacancy centers,” individual electrons are trapped. Their “spin” or intrinsic angular momentum is examined in this research.

When the resonator now begins to oscillate, strain develops in the diamond’s crystal structure. This, in turn, influences the spin of the electrons, which can indicate two possible directions (“up” or “down”) when measured. The direction of the spin can be detected with the aid of fluorescence spectroscopy.

Extremely fast spin oscillation

In this latest publication, the scientists have shaken the resonators in a way that allows them to induce a coherent oscillation of the coupled spin for the first time. This means that the spin of the electrons switches from up to down and vice versa in a controlled and rapid rhythm and that the scientists can control the spin status at any time. This spin oscillation is fast compared with the frequency of the resonator. It also protects the spin against harmful decoherence mechanisms.

It is conceivable that this diamond resonator could be applied to sensors – potentially in a highly sensitive way – because the oscillation of the resonator can be recorded via the altered spin. These new findings also allow the spin to be coherently rotated over a very long period of close to 100 microseconds, making the measurement more precise. Nitrogen-vacancy centers could potentially also be used to develop a quantum computer. In this case, the quick manipulation of its quantum states demonstrated in this work would be a decisive advantage.

Unfortunately, the researchers do not indicate the measurement scale for the diamonds so I’m guessing, given the descriptions, that these were nanoscale diamonds being used in the research.

In any event, here’s a link to and a citation for the paper,

Strong mechanical driving of a single electron spin by A. Barfuss, J. Teissier, E. Neu, A. Nunnenkamp, & P. Maletinsky. Nature Physics (2015)  doi:10.1038/nphys3411 Published online 03 August 2015

This paper is behind a paywall.

Slaughterhouse yarn (scientists looking for business investment)

Not everyone is going to feel comfortable with the idea of using gelatine to create fibres for yarn. Nonetheless, here’s a July 29, 2015 ETH Zurich (Swiss Federal Institute of Technology in Zurich, [Eidgenössische Technische Hochschule Zürich]) press release (also on EurekAlert) describes the research (a plea for business investment follows),

Some 70 million tonnes of fibres are traded worldwide every year. Man-made fibres manufactured from products of petroleum or natural gas account for almost two-thirds of this total. The most commonly used natural fibres are wool and cotton, but they have lost ground against synthetic fibres.

Despite their environmental friendliness, fibres made of biopolymers from plant or animal origin remain very much a niche product. At the end of the 19th century, there were already attempts to refine proteins into textiles. For example, a patent for textiles made of gelatine was filed in 1894. After the Second World War, however, the emerging synthetic fibres drove biological protein fibres swiftly and thoroughly from the market.

Over the past few years, there has been increased demand for natural fibres produced from renewable resources using environmentally friendly methods. Wool fibre in particular has experienced a renaissance in performance sportswear made of merino wool. And a few years ago, a young entrepreneur in Germany started making high-quality textiles from the milk protein casein.

New use for waste product

Now Philipp Stössel, a 28-year-old PhD student in Professor Wendelin Stark’s Functional Materials Laboratory (FML), is presenting a new method for obtaining high-quality fibres from gelatine. The method was developed in cooperation with the Advanced Fibers Laboratory at Empa St. Gallen. Stössel was able to spin the fibres into a yarn from which textiles can be manufactured.

Gelatine consists chiefly of collagen, a main component of skin, bone and tendons. Large quantities of collagen are found in slaughterhouse waste and can be easily made into gelatine. For these reasons, Stark and Stössel decided to use this biomaterial for their experiments.

Coincidence helps provide a solution

In his experiments, Stössel noticed that when he added an organic solvent (isopropyl) to a heated, aqueous gelatine solution, the protein precipitated at the bottom of the vessel. He removed the formless mass using a pipette and was able to effortlessly press an elastic, endless thread from it. This was the starting point for his unusual research work.

As part of his dissertation, Stössel developed and refined the method, which he has just recently presented in an article for the journal Biomacromolecules.

The refined method replaces the pipette with several syringe drivers in a parallel arrangement. Using an even application of pressure, the syringes push out fine endless filaments, which are guided over two Teflon-coated rolls. The rolls are kept constantly moist in an ethanol bath; this prevents the filaments from sticking together and allows them to harden quickly before they are rolled onto a conveyor belt. Using the spinning machine he developed, Stössel was able to produce 200 metres of filaments a minute. He then twisted around 1,000 individual filaments into a yarn with a hand spindle and had a glove knitted from the yarn as a showpiece.

Attractive luster

Extremely fine, the individual fibres have a diameter of only 25 micrometres, roughly half the thickness of a human hair. With his first laboratory spinning machines, the fibre thickness was 100 micrometres, Stössel recalls. That was too thick for yarn production.

Whereas natural wool fibres have tiny scales, the surface of the gelatine fibres is smooth. “As a result, they have an attractive luster,” Stössel says. Moreover, the interior of the fibres is filled with cavities, as shown by the researchers’ electron microscope images. This might also be the reason for the gelatine yarn’s good insulation, which Stössel was able to measure in comparison with a glove made of merino wool.

Water-resistant fibres

Gelatine’s major drawback is that it its water-solubility. Stössel had to greatly improve the water resistance of the gelatine yarn through various chemical processing stages. First he treated the glove with an epoxy in order to bond the gelatine components more firmly together. Next, he treated the material with formaldehyde so that it would harden better. Finally, he impregnated the yarn with lanolin, a natural wool grease, to make it supple.

As he completes his dissertation over the coming months, Stössel will research how to make the gelatine fibres even more water-resistant. Sheep’s wool is still superior to the gelatine yarn in this respect. However, Stössel is convinced that he is very close to his ultimate goal: making a biopolymer fibre from a waste product.

It’s been a few months since I’ve seen one of these pleas for commercial interest/partnership (from the press release),

Three years ago, the researchers applied for a patent on their invention. Stössel explains that they have reached the point where their capacity in the laboratory is at its limit, but commercial production will only be possible if they can find partners and funding.

Here’s a link to and a citation for the researchers’ latest published paper (there are also two previous paper listed in the press release),

Porous, Water-Resistant Multifilament Yarn Spun from Gelatin by Philipp R. Stoessel, Urs Krebs, Rudolf Hufenus, Marcel Halbeisen, Martin Zeltner, Robert N. Grass, and Wendelin J. Stark. Biomacromolecules, 2015, 16 (7), pp 1997–2005 DOI: 10.1021/acs.biomac.5b00424 Publication Date (Web): June 2, 2015

Copyright © 2015 American Chemical Society

This paper is behind a paywall.

Putting the speed on spin, spintronics that is

This is for physics fans, if you plan on looking at the published paper. Otherwise, the July 20, 2015 news item on ScienceDaily is more accessible to the rest of us,

In a tremendous boost for spintronic technologies, EPFL scientists have shown that electrons can jump through spins much faster than previously thought.

Electrons spin around atoms, but also spin around themselves, and can cross over from one spin state to another. A property which can be exploited for next-generation hard drives. However, “spin cross-over” has been considered too slow to be efficient. Using ultrafast measurements, EPFL scientists have now shown for the first time that electrons can cross spins at least 100,000 times faster than previously thought. Aside for its enormous implications for fundamental physics, the finding can also propel the field of spintronics forward. …

A July 20, 2015 EPFL press release on EurekAlert, which originated the news item, provides context for the research,

The rules of spin

Although difficult to describe in everyday terms, electron spin can be loosely compared to the rotation of a planet or a spinning top around its axis. Electrons can spin in different manners referred to as “spin states” and designated by the numbers 0, 1/2, 1, 3/2, 2 etc. During chemical reactions, electrons can cross from one spin state to another, e.g. from 0 to 1 or 1/2 to 3/2.

Spin cross-over is already used in many technologies, e.g. optical light-emitting devices (OLED), energy conversion systems, and cancer phototherapy. Most prominently, spin cross-over is the basis of the fledgling field of spintronics. The problem is that spin cross-over has been thought to be too slow to be efficient enough in circuits.

Spin cross-over is extremely fast

The lab of Majed Chergui at EPFL has now demonstrated that spin cross-over is considerably faster than previously thought. Using the highest time-resolution technology in the world, the lab was able to “see” electrons crossing through four spin states within 50 quadrillionths of a second — or 50 femtoseconds.

“Time resolution has always been a limitation,” says Chergui. “Over the years, labs have used techniques that could only measure spin changes to a billionth to a millionth of a second. So they thought that spin cross-over happened in this timeframe.”

Chergui’s lab focused on materials that show much promise in spintronics applications. In these materials, electrons jump through four spin-states: from 0 to 1 to 2. In 2009, Chergui’s lab pushed the boundaries of time resolution to show that this 0-2 “jump” can happen within 150 femtoseconds — suggesting that it was a direct event. Despite this, the community still maintained that such spin cross-overs go through intermediate steps.

But Chergui had his doubts. Working with his postdoc Gerald Auböck, they used the lab’s world-recognized expertise in ultrafast spectroscopy to “crank up” the time resolution. Briefly, a laser shines on the material sample under investigation, causing its electrons to move. Another laser measures their spin changes over time in the ultraviolet light range.

The finding essentially demolishes the notion of intermediate steps between spin jumps, as it does not allow enough time for them: only 50 quadrillionths of a second to go from the “0” to the “2” spin state. This is the first study to ever push time resolution to this limit in the ultraviolet domain. “This probably means that it’s even faster,” says Chergui. “But, more importantly, that it is a direct process.”

From observation to explanation

With profound implications for both technology and fundamental physics and chemistry, the study is an observation without an explanation. Chergui believes that the key is electrons shuttling back-and-forth between the iron atom at the center of the material’s molecules and its surrounding elements. “When the laser light shines on the atom, it changes the electron’s spin angle, affecting the entire spin dynamics in the molecule.”

It is now up to theoreticians to develop a new model for ultrafast spin changes. On the experimental side of things, Chergui’s lab is now focusing on actually observing electrons shuttling inside the molecules. This will require even more sophisticated approaches, such as core-level spectroscopy. Nonetheless, the study challenges ideas about spin cross-over, and might offer long-awaited solutions to the limitations of spintronics.

Here’s a link to and citation for the paper,

Sub-50-fs photoinduced spin crossover in [Fe(bpy)3]2+ by Gerald Auböck & Majed Chergui. Nature Chemistry (2015) doi:10.1038/nchem.2305 Published online 20 July 2015

This paper is behind a paywall.

Nanotechnology research protocols for Environment, Health and Safety Studies in US and a nanomedicine characterization laboratory in the European Union

I have two items relating to nanotechnology and the development of protocols. The first item concerns the launch of a new web portal by the US National Institute of Standards and Technology.

US National Institute of Standards and Technology (NIST)

From a July 1, 2015 news item on Azonano,

As engineered nanomaterials increasingly find their way into commercial products, researchers who study the potential environmental or health impacts of those materials face a growing challenge to accurately measure and characterize them. These challenges affect measurements of basic chemical and physical properties as well as toxicology assessments.

To help nano-EHS (Environment, Health and Safety)researchers navigate the often complex measurement issues, the National Institute of Standards and Technology (NIST) has launched a new website devoted to NIST-developed (or co-developed) and validated laboratory protocols for nano-EHS studies.

A July 1, 2015 NIST news release on EurekAlert, which originated the news item, offers more details about the information available through the web portal,

In common lab parlance, a “protocol” is a specific step-by-step procedure used to carry out a measurement or related activity, including all the chemicals and equipment required. Any peer-reviewed journal article reporting an experimental result has a “methods” section where the authors document their measurement protocol, but those descriptions are necessarily brief and condensed, and may lack validation of any sort. By comparison, on NIST’s new Protocols for Nano-EHS website the protocols are extraordinarily detailed. For ease of citation, they’re published individually–each with its own unique digital object identifier (DOI).

The protocols detail not only what you should do, but why and what could go wrong. The specificity is important, according to program director Debra Kaiser, because of the inherent difficulty of making reliable measurements of such small materials. “Often, if you do something seemingly trivial–use a different size pipette, for example–you get a different result. Our goal is to help people get data they can reproduce, data they can trust.”

A typical caution, for example, notes that if you’re using an instrument that measures the size of nanoparticles in a solution by how they scatter light, it’s important also to measure the transmission spectrum of the particles if they’re colored, because if they happen to absorb light strongly at the same frequency as your instrument, the result may be biased.

“These measurements are difficult because of the small size involved,” explains Kaiser. “Very few new instruments have been developed for this. People are adapting existing instruments and methods for the job, but often those instruments are being operated close to their limits and the methods were developed for chemicals or bulk materials and not for nanomaterials.”

“For example, NIST offers a reference material for measuring the size of gold nanoparticles in solution, and we report six different sizes depending on the instrument you use. We do it that way because different instruments sense different aspects of a nanoparticle’s dimensions. An electron microscope is telling you something different than a dynamic light scattering instrument, and the researcher needs to understand that.”

The nano-EHS protocols offered by the NIST site, Kaiser says, could form the basis for consensus-based, formal test methods such as those published by ASTM and ISO.

NIST’s nano-EHS protocol site currently lists 12 different protocols in three categories: sample preparation, physico-chemical measurements and toxicological measurements. More protocols will be added as they are validated and documented. Suggestions for additional protocols are welcome at nanoprotocols@nist.gov.

The next item concerns European nanomedicine.

CEA-LETI and Europe’s first nanomedicine characterization laboratory

A July 1, 2015 news item on Nanotechnology Now describes the partnership which has led to launch of the new laboratory,

CEA-Leti today announced the launch of the European Nano-Characterisation Laboratory (EU-NCL) funded by the European Union’s Horizon 2020 research and innovation programm[1]e. Its main objective is to reach a level of international excellence in nanomedicine characterisation for medical indications like cancer, diabetes, inflammatory diseases or infections, and make it accessible to all organisations developing candidate nanomedicines prior to their submission to regulatory agencies to get the approval for clinical trials and, later, marketing authorization.

“As reported in the ETPN White Paper[2], there is a lack of infrastructure to support nanotechnology-based innovation in healthcare,” said Patrick Boisseau, head of business development in nanomedicine at CEA-Leti and chairman of the European Technology Platform Nanomedicine (ETPN). “Nanocharacterisation is the first bottleneck encountered by companies developing nanotherapeutics. The EU-NCL project is of most importance for the nanomedicine community, as it will contribute to the competiveness of nanomedicine products and tools and facilitate regulation in Europe.”

EU-NCL is partnered with the sole international reference facility, the Nanotechnology Characterization Lab of the National Cancer Institute in the U.S. (US-NCL)[3], to get faster international harmonization of analytical protocols.

“We are excited to be part of this cooperative arrangement between Europe and the U.S.,” said Scott E. McNeil, director of U.S. NCL. “We hope this collaboration will help standardize regulatory requirements for clinical evaluation and marketing of nanomedicines internationally. This venture holds great promise for using nanotechnologies to overcome cancer and other major diseases around the world.”

A July 2, 2015 EMPA (Swiss Federal Laboratories for Materials Science and Technology) news release on EurekAlert provides more detail about the laboratory and the partnerships,

The «European Nanomedicine Characterization Laboratory» (EU-NCL), which was launched on 1 June 2015, has a clear-cut goal: to help bring more nanomedicine candidates into the clinic and on the market, for the benefit of patients and the European pharmaceutical industry. To achieve this, EU-NCL is partnered with the sole international reference facility, the «Nanotechnology Characterization Laboratory» (US-NCL) of the US-National Cancer Institute, to get faster international harmonization of analytical protocols. EU-NCL is also closely connected to national medicine agencies and the European Medicines Agency to continuously adapt its analytical services to requests of regulators. EU-NCL is designed, organized and operated according to the highest EU regulatory and quality standards. «We are excited to be part of this cooperative project between Europe and the U.S.,» says Scott E. McNeil, director of US-NCL. «We hope this collaboration will help standardize regulatory requirements for clinical evaluation and marketing of nanomedicines internationally. This venture holds great promise for using nanotechnologies to overcome cancer and other major diseases around the world.»

Nine partners from eight countries

EU-NCL, which is funded by the EU for a four-year period with nearly 5 million Euros, brings together nine partners from eight countries: CEA-Tech in Leti and Liten, France, the coordinator of the project; the Joint Research Centre of the European Commission in Ispra, Italy; European Research Services GmbH in Münster Germany; Leidos Biomedical Research, Inc. in Frederick, USA; Trinity College in Dublin, Ireland; SINTEF in Oslo, Norway; the University of Liverpool in the UK; Empa, the Swiss Federal Laboratories for Materials Science and Technology in St. Gallen, Switzerland; Westfälische Wilhelms-Universität (WWU) and Gesellschaft für Bioanalytik, both in Münster, Germany. Together, the partnering institutions will provide a trans-disciplinary testing infrastructure covering a comprehensive set of preclinical characterization assays (physical, chemical, in vitro and in vivo biological testing), which will allow researchers to fully comprehend the biodistribution, metabolism, pharmacokinetics, safety profiles and immunological effects of their medicinal nano-products. The project will also foster the use and deployment of standard operating procedures (SOPs), benchmark materials and quality management for the preclinical characterization of medicinal nano-products. Yet another objective is to promote intersectoral and interdisciplinary communication among key drivers of innovation, especially between developers and regulatory agencies.

The goal: to bring safe and efficient nano-therapeutics faster to the patient

Within EU-NCL, six analytical facilities will offer transnational access to their existing analytical services for public and private developers, and will also develop new or improved analytical assays to keep EU-NCL at the cutting edge of nanomedicine characterization. A complementary set of networking activities will enable EU-NCL to deliver to European academic or industrial scientists the high-quality analytical services they require for accelerating the industrial development of their candidate nanomedicines. The Empa team of Peter Wick at the «Particles-Biology Interactions» lab will be in charge of the quality management of all analytical methods, a key task to guarantee the best possible reproducibility and comparability of the data between the various analytical labs within the consortium. «EU-NCL supports our research activities in developing innovative and safe nanomaterials for healthcare within an international network, which will actively shape future standards in nanomedicine and strengthen Empa as an enabler to facilitate the transfer of novel nanomedicines from bench to bedside», says Wick.

You can find more information about the laboratory on the Horizon 2020 (a European Union science funding programme) project page for the EU-NCL laboratory. For anyone curious about CEA-Leti, it’s a double-layered organization. CEA is France’s Commission on Atomic Energy and Alternative Energy (Commissariat à l’énergie atomique et aux énergies alternatives); you can go here to their French language site (there is an English language clickable option on the page). Leti is one of the CEA’s institutes and is known as either Leti or CEA-Leti. I have no idea what Leti stands for. Here’s the Leti website (this is the English language version).

Saharan silver ants: the nano of it all (science and technology)

Researchers at Columbia University (US) are on quite a publishing binge lately. The latest is a biomimicry story where researchers (from Columbia amongst other universities and including Brookhaven National Laboratory, which has issued its own news release) have taken a very close look at Saharan silver ants to determine how they stay cool in one of the hottest climates in the world. From a June 18, 2015 Columbia University news release (also on EurekAlert), Note: Links have been removed,

Nanfang Yu, assistant professor of applied physics at Columbia Engineering, and colleagues from the University of Zürich and the University of Washington, have discovered two key strategies that enable Saharan silver ants to stay cool in one of the hottest terrestrial environments on Earth. Yu’s team is the first to demonstrate that the ants use a coat of uniquely shaped hairs to control electromagnetic waves over an extremely broad range from the solar spectrum (visible and near-infrared) to the thermal radiation spectrum (mid-infrared), and that different physical mechanisms are used in different spectral bands to realize the same biological function of reducing body temperature. Their research, “Saharan silver ants keep cool by combining enhanced optical reflection and radiative heat dissipation,” is published June 18 [2015] in Science magazine.

The Columbia University news release expands on the theme,

“This is a telling example of how evolution has triggered the adaptation of physical attributes to accomplish a physiological task and ensure survival, in this case to prevent Saharan silver ants from getting overheated,” Yu says. “While there have been many studies of the physical optics of living systems in the ultraviolet and visible range of the spectrum, our understanding of the role of infrared light in their lives is much less advanced. Our study shows that light invisible to the human eye does not necessarily mean that it does not play a crucial role for living organisms.”

The project was initially triggered by wondering whether the ants’ conspicuous silvery coats were important in keeping them cool in blistering heat. Yu’s team found that the answer to this question was much broader once they realized the important role of infrared light. Their discovery that there is a biological solution to a thermoregulatory problem could lead to the development of novel flat optical components that exhibit optimal cooling properties.

“Such biologically inspired cooling surfaces will have high reflectivity in the solar spectrum and high radiative efficiency in the thermal radiation spectrum,” Yu explains. “So this may generate useful applications such as a cooling surface for vehicles, buildings, instruments, and even clothing.”

Saharan silver ants (Cataglyphis bombycina) forage in the Saharan Desert in the full midday sun when surface temperatures reach up to 70°C (158°F), and they must keep their body temperature below their critical thermal maximum of 53.6°C (128.48°F) most of the time. In their wide-ranging foraging journeys, the ants search for corpses of insects and other arthropods that have succumbed to the thermally harsh desert conditions, which they are able to endure more successfully. Being most active during the hottest moment of the day also allows these ants to avoid predatory desert lizards. Researchers have long wondered how these tiny insects (about 10 mm, or 3/8” long) can survive under such thermally extreme and stressful conditions.

Using electron microscopy and ion beam milling, Yu’s group discovered that the ants are covered on the top and sides of their bodies with a coating of uniquely shaped hairs with triangular cross-sections that keep them cool in two ways. These hairs are highly reflective under the visible and near-infrared light, i.e., in the region of maximal solar radiation (the ants run at a speed of up to 0.7 meters per second and look like droplets of mercury on the desert surface). The hairs are also highly emissive in the mid-infrared portion of the electromagnetic spectrum, where they serve as an antireflection layer that enhances the ants’ ability to offload excess heat via thermal radiation, which is emitted from the hot body of the ants to the cold sky. This passive cooling effect works under the full sun whenever the insects are exposed to the clear sky.

“To appreciate the effect of thermal radiation, think of the chilly feeling when you get out of bed in the morning,” says Yu. “Half of the energy loss at that moment is due to thermal radiation since your skin temperature is temporarily much higher than that of the surrounding environment.”

The researchers found that the enhanced reflectivity in the solar spectrum and enhanced thermal radiative efficiency have comparable contributions to reducing the body temperature of silver ants by 5 to 10 degrees compared to if the ants were without the hair cover. “The fact that these silver ants can manipulate electromagnetic waves over such a broad range of spectrum shows us just how complex the function of these seemingly simple biological organs of an insect can be,” observes Norman Nan Shi, lead author of the study and PhD student who works with Yu at Columbia Engineering.

Yu and Shi collaborated on the project with Rüdiger Wehner, professor at the Brain Research Institute, University of Zürich, Switzerland, and Gary Bernard, electrical engineering professor at the University of Washington, Seattle, who are renowned experts in the study of insect physiology and ecology. The Columbia Engineering team designed and conducted all experimental work, including optical and infrared microscopy and spectroscopy experiments, thermodynamic experiments, and computer simulation and modeling. They are currently working on adapting the engineering lessons learned from the study of Saharan silver ants to create flat optical components, or “metasurfaces,” that consist of a planar array of nanophotonic elements and provide designer optical and thermal radiative properties.

Yu and his team plan next to extend their research to other animals and organisms living in extreme environments, trying to learn the strategies these creatures have developed to cope with harsh environmental conditions.

“Animals have evolved diverse strategies to perceive and utilize electromagnetic waves: deep sea fish have eyes that enable them to maneuver and prey in dark waters, butterflies create colors from nanostructures in their wings, honey bees can see and respond to ultraviolet signals, and fireflies use flash communication systems,” Yu adds. “Organs evolved for perceiving or controlling electromagnetic waves often surpass analogous man-made devices in both sophistication and efficiency. Understanding and harnessing natural design concepts deepens our knowledge of complex biological systems and inspires ideas for creating novel technologies.”

Next, there’s the perspective provided by Brookhaven National Laboratory in a June 18, 2015 news item on Nanowerk (Note: It is very similar to the Columbia University news release but it takes a turn towards the technical challenges as you’ll see if you keep reading),

The paper, published by Columbia Engineering researchers and collaborators—including researchers from the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory—describes how the nanoscale structure of the hairs helps increase the reflectivity of the ant’s body in both visible and near-infrared wavelengths, allowing the insects to deflect solar radiation their bodies would otherwise absorb. The hairs also enhance emissivity in the mid-infrared spectrum, allowing heat to dissipate efficiently from the hot body of the ants to the cool, clear sky.

A June 18, 2015 BNL news release by Alasdair Wilkins, which originated the Nanowerk news item, describes the collaboration between the researchers and the special adjustments made to the equipment in service of this project (Note: A link has been removed),

In a typical experiment involving biological material such as nanoscale hairs, it would usually be sufficient to use an electron microscope to create an image of the surface of the specimen. This research, however, required Yu’s group to look inside the ant hairs and produce a cross-section of the structure’s interior. The relatively weak beam of electrons from a standard electron microscope would not be able to penetrate the surface of the sample.

The CFN’s dual beam system solves the problem by combining the imaging of an electron microscope with a much more powerful beam of gallium ions.  With 31 protons and 38 neutrons, each gallium ion is about 125,000 times more massive than an electron, and massive enough to create dents in the nanoscale structure – like throwing a stone against a wall. The researchers used these powerful beams to drill precise cuts into the hairs, revealing the crucial information hidden beneath the surface. Indeed, this particular application, in which the system was used to investigate a biological problem, was new for the team at CFN.

“Conventionally, this tool is used to produce cross-sections of microelectronic circuits,” said Camino. “The focused ion beam is like an etching tool. You can think of it like a milling tool in a machine shop, but at the nanoscale. It can remove material at specific places because you can see these locations with the SEM. So locally you remove material and you look at the under layers, because the cuts give you access to the cross section of whatever you want to look at.”

The ant hair research challenged the CFN team to come up with novel solutions to investigate the internal structures without damaging the more delicate biological samples.

“These hairs are very soft compared to, say, semiconductors or crystalline materials. And there’s a lot of local heat that can damage biological samples. So the parameters have to be carefully tuned not to do much damage to it,” he said. “We had to adapt our technique to find the right conditions.”

Another challenge lay in dealing with the so-called charging effect. When the dual beam system is trained on a non-conducting material, electrons can build up at the point where the beams hit the specimen, distorting the resulting image. The team at CFN was able to solve this problem by placing thin layers of gold over the biological material, making the sample just conductive enough to avoid the charging effect.

Revealing Reflectivity

While Camino’s team focused on helping Yu’s group investigate the structure of the ant hairs, Matthew Sfeir’s work with high-brightness Fourier transform optical spectroscopy helped to reveal how the reflectivity of the hairs helped Saharan silver ants regulate temperature. Sfeir’s spectrometer revealed precisely how much those biological structures reflect light across multiple wavelengths, including both visible and near-infrared light.

“It’s a multiplexed measurement,” Sfeir said, explaining his team’s spectrometer. “Instead of tuning through this wavelength and this wavelength, that wavelength, you do them all in one swoop to get all the spectral information in one shot. It gives you very fast measurements and very good resolution spectrally. Then we optimize it for very small samples. It’s a rather unique capability of CFN.”

Sfeir’s spectroscopy work draws on knowledge gained from his work at another key Brookhaven facility: the original National Synchrotron Light Source, where he did much of his postdoc work. His experience was particularly useful in analyzing the reflectivity of the biological structures across many different wavelengths of the electromagnetic spectrum.

“This technique was developed from my experience working with the infrared synchrotron beamlines,” said Sfeir. “Synchrotron beamlines are optimized for exactly this kind of thing. I thought, ‘Hey, wouldn’t it be great if we could develop a similar measurement for the type of solar devices we make at CFN?’ So we built a bench-top version to use here.”

Fascinating, non? At last, here’s a link to and a citation for the paper,

Keeping cool: Enhanced optical reflection and heat dissipation in silver ants by Norman Nan Shi, Cheng-Chia Tsai, Fernando Camino, Gary D. Bernard, Nanfang Yu, and Rüdiger Wehner. Science DOI: 10.1126/science.aab3564 Published online June 18, 2015

This paper is behind a paywall.

Tanzanian research into nanotechnology-enabled water filters

Inexpensive 99.9999…% filtration of metals, bacteria, and viruses from water is an accomplishment worthy of a prize as the UK’s Royal Academy of Engineering noted by awarding its first ever International Innovation Prize of £25,000 ($38,348 [USD?]) to Askwar Hilonga, a Tanzanian academic and entrepreneur. A June 11, 2015 article by Sibusiso Tshabalala for Quartz.com describes the water situation in Tanzania and Hilonga’s accomplishment (Note: Links have been removed),

Despite Tanzania’s proximity to three major lakes almost half of it’s population cannot access potable water.

Groundwater is often the alternative, but the supply is not always clean. Mining waste (pdf, pg 410) and toxic drainage systems easily leak into fresh groundwater, leaving the water contaminated.

Enter Askwar Hilonga: a 38-year old chemical engineer PhD and entrepreneur. With 33 academic journal articles on nanotechnology to his name, Hilonga aims to solve Tanzania’s water contamination problems by using nanotechnology to customize water filters.

There are other filters available (according to Tshabalala’s article) but Hilonga’s has a unique characteristic in addition to being highly efficient and inexpensive,

Purifying water using nanotechnology is hardly a new thing. In 2010, researchers at the Yi Cui Lab at Stanford University developed a synthetic “nanoscanvenger” made out of two silver layers that enable nanoparticles to disinfect water from contaminating bacteria.

What makes Hilonga’s water filter different from the Stanford-developed “nanoscavenger”, or the popular LifeStraw developed by the Swiss-based health innovation company Vestergaard 10 years ago?

“It is customized. The filter can be tailored for specific individual, household and communal use,” says Hilonga.

A June 2, 2015 news item about the award on BBC (British Broadcasting Corporation) online describes how the filter works,

The sand-based water filter that cleans contaminated drinking water using nanotechnology has already been trademarked.

“I put water through sand to trap debris and bacteria,” Mr Hilonga told the BBC’s Newsday programme about the filter.

“But sand cannot remove contaminants like fluoride and other heavy metals so I put them through nano materials to remove chemical contaminants.”

Hilonga describes the filter in a little more detail in his May 30, 2014 video submitted for for the UK Royal Academy of Engineering’s prize (Africa Prize for Engineering Innovation)

Finalists for the prize (there were four) received a six month mentorship which included help to develop the technology further and with business plans. Hilonga has already enabled 23 entrepreneurs to develop nanofilter businesses, according to the Tshabalala article,

Through the Gongali Model Company, a university spin-off company which he co-founded, Hilonga has already enabled 23 entrepreneurs in Karatu to set up their businesses with the filters, and local schools to provide their learners with clean drinking water.

With this prize money, Hilonga will be able to lower the price of his filter ($130 [USD?) according to the BBC news item.

Congratulations to Dr. Hilonga and his team! For anyone curious about the Gongali Model Company, you can go here.