Category Archives: environment

Food and nanotechnology (as per Popular Mechanics) and zinc oxide nanoparticles in soil (as per North Dakota State University)

I wouldn’t expect to find an article about food in a magazine titled Popular Mechanics but there it is, a Feb. 19,2014 article by Christina Ortiz (Note: A link has been removed),

For a little more than a decade, the food industry has been using nanotechnology to change the way we grow and maintain our food. The grocery chain Albertsons currently has a list of nanotech-touched foods in its home brand, ranging from cookies to cheese blends.

Nanotechnology use in food has real advantages: The technology gives producers the power to control how food looks, tastes, and even how long it lasts.

Looks Good and Good for You?

The most commonly used nanoparticle in foods is titanium dioxide. It’s used to make foods such as yogurt and coconut flakes look as white as possible, provide opacity to other food colorings, and prevent ingredients from caking up. Nanotech isn’t just about aesthetics, however. The biggest potential use for this method involves improving the nutritional value of foods.

Nano additives can enhance or prevent the absorption of certain nutrients. In an email interview with Popular Mechanics, Jonathan Brown, a research fellow at the University of Minnesota, says this method could be used to make mayonnaise less fattening by replacing fat molecules with water droplets.

I did check out US grocer, Albertson’s list of ‘nanofoods’, which they provide and discovered that it’s an undated listing on the Project of Emerging Nanotechnologies’ Consumer Products Inventory (CPI). The inventory has been revived recently after lying moribund for a few years (my Oct. 28, 2013 posting describes the fall and rise) and I believe that this 2013 CPI incarnation includes some oversight and analysis of the claims made, which the earlier version did not include. Given that the Albertson’s list is undated it’s difficult to assess the accuracy of the claims regarding the foodstuffs.

If you haven’t read about nanotechnology and food before, the Ortiz article provides a relatively even-handed primer although it does end on a cautionary note. In any event, it was interesting to get a bit of information about the process of ‘nanofood’ regulation in the US and other jurisdictions (from the Ortiz article),

Aside from requiring manufacturers to provide proof that nanotechnology foods are safe, the FDA has yet to implement specific testing of its own. But many countries are researching ways to balance innovation and regulation in this market. In 2012 the European Food Safety Authority (EFSA) released an annual risk assessment report outlining how the European Union is addressing the issue of nanotech in food. In Canada the Food Directorate “is taking a case-by-case approach to the safety assessment of food products containing or using nanomaterials.”

I featured the FDA’s efforts regarding regulation and ‘nanofood’ in an April 23, 2012 posting,

It looks to me like this [FDA's draft guidance for 'nanofoods'] is an attempt to develop a relationship where the industry players in the food industry to police their nanotechnology initiatives with the onus being on industry to communicate with the regulators in a continuous process, if not at the research stage certainly at the production stage.

At least one of the primary issues with any emerging technology revolves around the question of risk. Do we stop all manufacturing and development of nanotechnology-enabled food products until we’ve done the research? That question assumes that taking any risks is not worth the currently perceived benefits. The corresponding question, do we move forward and hope for the best? does get expressed perhaps not quite so baldly; I have seen material which suggests that research into risks needlessly hampers progress.

After reading on this topic for five or so years, my sense is that most people are prepared to combine the two approaches, i.e., move forward while researching possible risks. The actual conflicts seem to centre around these questions, how quickly do we move forward; how much research do we need; and what is an acceptable level of risk?

On the topic of researching the impact that nanoparticles might have on plants (food or otherwise), a January 24, 2013 North Dakota State University (NDSU) news release highlights a student researcher’s work on soil, plants, and zinc oxide nanoparticles,

NDSU senior Hannah Passolt is working on a project that is venturing into a very young field of research. The study about how crops’ roots absorb a microscopic nutrient might be described as being ahead of the cutting-edge.

In a laboratory of NDSU’s Wet Ecosystem Research Group, in collaboration with plant sciences, Passolt is exploring how two varieties of wheat take up extremely tiny pieces of zinc, called nanoparticles, from the soil.

As a point of reference, the particles Passolt is examining are measured at below 30 nanometers. A nanometer is 1 billionth of a meter.

“It’s the mystery of nanoparticles that is fascinating to me,” explained the zoology major from Fargo. “The behavior of nanoparticles in the environment is largely unknown as it is a very new, exciting science. This type of project has never been done before.”

In Passolt’s research project, plants supplied by NDSU wheat breeders are grown in a hydroponic solution, with different amounts of zinc oxide nanoparticles introduced into the solution.

Compared to naturally occurring zinc, engineered zinc nanoparticles can have very different properties. They can be highly reactive, meaning they can injure cells and tissues, and may cause genetic damage. The plants are carefully observed for any changes in growth rate and appearance. When the plants are harvested, researchers will analyze them for actual zinc content.

“Zinc is essential for a plant’s development. However, in excess, it can be harmful,” Passolt said. “In one of my experiments, we are using low and high levels of zinc, and the high concentrations are showing detrimental effects. However, we will have to analyze the plants for zinc concentrations to see if there have been any effects from the zinc nanoparticles.”

Passolt has conducted undergraduate research with the Wet Ecosystem Research Group for the past two years. She said working side-by-side with Donna Jacob, research assistant professor of biological sciences; Marinus Otte; professor of biological sciences; and Mohamed Mergoum, professor of plant sciences, has proven to be challenging, invigorating and rewarding.

“I’ve gained an incredible skill set – my research experience has built upon itself. I’ve gotten to the point where I have a pretty big role in an important study. To me, that is invaluable,” Passolt said. “To put effort into something that goes for the greater good of science is a very important lesson to learn.”

According to Jacob, Passolt volunteered two years ago, and she has since become an important member of the group. She has assisted graduate students and worked on her own small project, the results of which she presented at regional and international scientific conferences. “We offered her this large, complex experiment, and she’s really taken charge,” Jacob said, noting Passolt assisted with the project’s design, handled care of the plants and applied the treatments. When the project is completed, Passolt will publish a peer-reviewed scientific article.

“There is nothing like working on your own experiment to fully understand science,” Jacob said. “Since coming to NDSU in 2006, the Wet Ecosystem Research Group has worked with more than 50 undergraduates, possible only because of significant support from the North Dakota IDeA Networks of Biomedical Research Excellence program, known as INBRE, of the NIH National Center for Research Resources.”

Jacob said seven undergraduate students from the lab have worked on their own research projects and presented their work at conferences. Two articles, so far, have been published by undergraduate co-authors. “I believe the students gain valuable experience and an understanding of what scientists really do during fieldwork and in the laboratory,” Jacob said. “They see it is vastly different from book learning, and that scientists use creativity and ingenuity daily. I hope they come away from their experience with some excitement about research, in addition to a better resume.”

Passolt anticipates the results of her work could be used in a broader view of our ecosystem. She notes zinc nanoparticles are an often-used ingredient in such products as lotions, sunscreens and certain drug delivery systems. “Zinc nanoparticles are being introduced into the environment,” she said. “It gets to plants at some point, so we want to see if zinc nanoparticles have a positive or negative effect, or no effect at all.”

Researching nanoparticles the effects they might have on the environment and on health is a complex process as there are many types of nanoparticles some of which have been engineered and some of which occur naturally, silver nanoparticles being a prime example of both engineered and naturally occurring nanoparticles. (As well, the risks may lie more with interactions between nanomaterials.) For an example of research, which seems similar to the NDSU effort, there’s this open access research article,

Low Concentrations of Silver Nanoparticles in Biosolids Cause Adverse Ecosystem Responses under Realistic Field Scenario by Benjamin P. Colman, Christina L. Arnaout, Sarah Anciaux, Claudia K. Gunsch, Michael F. Hochella Jr, Bojeong Kim, Gregory V. Lowry,  Bonnie M. McGill, Brian C. Reinsch, Curtis J. Richardson, Jason M. Unrine, Justin P. Wright, Liyan Yin, and Emily S. Bernhardt. PLoS ONE 2013; 8 (2): e57189 DOI: 10.1371/journal.pone.0057189

One last comment, the Wet Ecosystem Research Group (WERG) mentioned in the news release about Passolt has an interesting history (from the homepage; Note: Links have been removed),

Marinus Otte and Donna Jacob brought WERG to the Department of Biological Sciences in the Fall of 2006.  Prior to that, the research group had been going strong at University College Dublin, Ireland, since 1992.

The aims for the research group are to train graduate and undergraduate students in scientific research, particularly wetlands, plants, biogeochemistry, watershed ecology and metals in the environment.  WERG research  covers a wide range of scales, from microscopic (e.g. biogeochemical processes in the rhizosphere of plants) to landscape (e.g. chemical and ecological connectivity between prairie potholes across North Dakota).  Regardless of the scale, the central theme is biogeochemistry and the interactions between multiple elements in wet environments.

The group works to collaborate with a variety of researchers, including soil scientists, geologists, environmental engineers, microbiologists, as well as with groups underpinning management of natural resources, such the Minnesota Department of Natural Resources, the Department of Natural Resources of Red Lake Indian Reservation, and the North Dakota Department of Health, Division of Water Quality.

Currently, WERG has several projects, mostly in North Dakota and Minnesota.  Otte and Jacob are also Co-directors of the North Dakota INBRE Metal Analysis Core, providing laboratory facilities and mentoring for researchers in undergraduate colleges throughout the state. Otte and Jacob are also members of the Upper Midwest Aerospace Consortium.

NanoCelluComp (nanocellulose composites) goes to JEC Composites Show and Conference in Paris (France)

NanoCelluComp (nanocellulose composites), a European Commission-funded project under the European Union’s 7th Framework Programme, which is entering its final stage (2011 – 2014) will make an appearance (Exhibition Stand D83) at the JEC 2014 Composites Show and Conferences in Paris (France), 11-13th March, 2014.

I  profileded NanoCelluComp in a March 7, 2013 posting where I included excerpts from the project’s 4th newsletter. The 5th (August 2013) newsletter is available here. There is also a project flyer (PDF), which provides some additional insight into why the project was developed and what NanoCellulComp was attempting to accomplish,

Food processing of vegetables produces billions of tonnes of fibrous waste. The cellulose fibres contained within this waste have superior structural properties that with ‘green’ chemistry can be put to much better use. Composites containing cellulose extracted from carrot waste have already been incorporated in lightweight products such as fishing rods and steering wheels.

This material – Curran – while exhibiting good structural properties, does not have the strength of glass or carbon fibre reinforced plastics (GFRP and CFRP) and is further disadvantaged due to limited processability.

The NanoCelluComp Process Improving on Curran through:

Liberating microfibrillated cellulose (nanocellulose) from vegetable waste streams utilising an aqueous based process (thus decreasing energy consumption, and avoiding volatile chemicals).
 Improving mechanical properties by the controlled alignment and cross linking of nanocellulose fibrils.
 Combining the resultant fibres with bio-based resins to produce a 100% bio-composite (thus decreasing use of petroleum-based products).
 Ensuring compatibility of the bio-composite with current manufacturing processes (e.g. injection moulding, hand lay-up).
 Investigating the sustainability of the above processes and materials, compared to existing materials, through a full life-cycle assessment (LCA) and identifying promising application fields.

Most of the ‘nanocellulose’ material that I’ve covered has been focused on derivations from forest products however there is one other team (that I know of) led by researcher Alcides Leão of Brazil examining the possible uses of nanocellulose derived from pineapples and bananas. On that note, my June 13, 2011 posting titled: Transcript of nanocellulose fibre podcast interview with Alcides Leão, Ph.D., from São Paulo State University and/or my March 28, 2011 posting titled: Nanocellulose fibres, pineapples, bananas, and cars may be of interest.

Carbon dioxide as a source for new nanomaterials

Polish researchers have made a startling suggestion (from a Jan. 23, 2014 news item on Nanowerk),

In common perception, carbon dioxide is just a greenhouse gas, one of the major environmental problems of mankind. For Warsaw chemists CO2 became, however, something else: a key element of reactions allowing for creation of nanomaterials with unprecedented properties.

In reaction with carbon dioxide, appropriately designed chemicals allowed researchers from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw and the Faculty of Chemistry, Warsaw University of Technology, (WUT) for production of unprecedented nanomaterials.

Here’s an image the researchers use to illustrate their work,

Yellow tennis balls, spatially integrated in an adamant-like structure, symbolise crystal lattice of the microporous material resulting from self-assembly of nanoclusters. Orange balls imitate gas molecules that can adsorb in this material. The presentation is performed by Katarzyna Sołtys, a doctoral student from the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw. (Source: IPC PAS, Grzegorz Krzyżewski).

Yellow tennis balls, spatially integrated in an adamant-like structure, symbolise crystal lattice of the microporous material resulting from self-assembly of nanoclusters. Orange balls imitate gas molecules that can adsorb in this material. The presentation is performed by Katarzyna Sołtys, a doctoral student from the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw. (Source: IPC PAS, Grzegorz Krzyżewski).

The Jan. 23, 2014 IPC news release, which originated the news item, describes the work in more detail,

Carbon dioxide (CO2) is a natural component of Earth’s atmosphere. It is the most abundant carbon-based building block, and is involved in the synthesis of glucose, an energy carrier and building unit of paramount importance for living organisms.

“Carbon dioxide has been for years used in industrial synthesis of polymers. On the other hand, there has been very few research papers reporting fabrication of inorganic functional materials using CO2”, says Kamil Sokołowski, a doctoral student in IPC PAS.

Prof. Lewiński’s [Janusz Lewiński (IPC PAS, WUT)] group has shown that appropriately designed precursor compounds in reaction with carbon dioxide lead to fabrication of a microporous material (with pore diameters below 2 nm) resulting from self-assembly of luminescent nanoclusters. Novel microporous material, composed of building blocks with zinc carbonate core encapsulated in appropriately designed organic shell (hydroxyquinoline ligands), is highly luminescent, with photoluminescence quantum yield significantly higher than those of classical fluorescent compounds used in state-of-the-art OLEDs.

“Using carbon dioxide as a building block we were able to construct a highly porous and really highly luminescent material. Can it be used for construction of luminescent diodes or sensing devices? The discovery is new, the research work on the novel material is in progress, but we are deeply convinced that the answer is: yes”, says Sokołowski.

Already now it can be said that the novel material enjoys considerable interest. Polish and international patent applications were filed for the invention and the implementation work in cooperation with a joint venture company is in progress.

The design of precursors was inspired by nature, in particular by the binding of carbon dioxide in enzymatic systems of carbonic anhydrase, an enzyme responsible for fast metabolism of CO2 in human body. Effective enzyme activity is based on its active centre, where a hydroxyzinc (ZnOH) type reaction system is located.

“A hydroxyzinc reaction system occurs also in molecules of alkylzinc compounds, designed by us and used for fixation of carbon dioxide”, explains Sokołowski and continues: “These compounds are of particular interest for us, because in addition to hydroxyl group they contain also a reactive metal-carbon bond. It means that both the first and the second reaction system can participate in consecutive chemical transformations of such precursors”.

The research related to the chemistry of alkylhydroxyzinc compounds has an over 150 years of history and its roots are directly connected to the birth of organometallic chemistry. It was, however, only in 2011 and 2012 when Prof. Lewiński’s group has presented the first examples of stable alkylhydroxyzinc compounds obtained as a result of rationally designed synthesis.

The strategy for materials synthesis using carbon dioxide and appropriate alkylhydroxyzinc precursors, discovered by the researchers from Warsaw, seems to be a versatile tool for production of various functional materials. Depending on the composition of the reagents and the process conditions, a mesoporous material (with pore diameter from 2 to 50 nm) composed of zinc carbonate nanoparticles or multinuclear zinc nanocapsules for prospective applications in supramolecular chemistry can be obtained in addition to the material described above.

Further research of Prof. Lewiński’s group has shown that the mesoporous materials based on ZnCO3-nanoparticles can be transformed into zinc oxide (ZnO) aerogels. Mesoporous materials made of ZnO nanoparticles with extended surface can be used as catalytic fillings, allowing for and accelerating reactions of various gaseous reagents. Other potential applications are related to semiconducting properties of zinc oxide. That’s why the novel materials can be used in future in photovoltaic cells or as a major component of semiconductor sensing devices.

Good luck to the researchers as they find ways to turn a greenhouse gas into something useful.

Few nanoparticles shed in nanopaint tests

Empa, Swiss Federal Laboratories for Materials Science and Technology, led a 3.5 year project, NanoHouse, investigating whether or not nanoparticles added to paint used on building facades might prove a health hazard. From a Jan. 13, 2014 news item on Nanowerk (Note: A link has been removed),

 After 42 months the EU research project “NanoHouse” has ended, and the verdict is a cautious “all clear” – nanoparticles in the paint used on building façades do not represent a particular health risk. In the course of a “Technology Briefing” Empa researchers discussed these results with specialists from the construction industry.

Five Empa laboratories were involved in the EU NanoHouse project, along with four other European research institutes and four industrial partners. The aim of the project was to investigate the opportunities and risks presented by the nanomaterials used in the surface coatings applied to building façades. For the first time not only were freshly manufactured products studied to see if they set free nanoparticles, but also aged samples.

The January 13, 2014 Empa press release, which originated the news item, provides more details about the recent  NanoHouse technology briefing,

… Claudia Som briefly introduced the «NanoHouse» project, for which she acted as Empa coordinator. This project, which is financially supported through the EU’s 7th Research Framework Program, began in 2010 with the aim of investigating possible health effects caused by nanoparticles in building materials and houses. Various aspects of the research program included rubbing tests on model façades, attempts to wash out nanoparticles from surface coatings and an analysis of the biological effects on humans and the environment.

Tina Kuenniger, an Empa expert on the protection of wood surfaces against weathering, explained how nanoparticles work in paint. Some paints containing silicon dioxide are water repellent, easy to clean and scratch resistant. Nano titanium-dioxide has photocatalytic properties and can decompose air pollutants. Nano titanium-dioxide, along with nano zinc-oxide and nano-iron oxide, can be used to provide UV protection and, depending on the size of the particles used, also to protect against infrared radiation, i.e. heat. Similarly, nanoparticles can protect against attack by blue stain fungus and algae. Whilst many laboratory studies have confirmed the effectiveness of nanoparticles, in practice one question remains open: how much of the nanomaterial does one have to mix with the paint to ensure that it functions as expected? For this reason only a few products for external façades containing nano-materials are available on the market to date. The greatest opportunity nanoparticles offer lies in the combination of various functional properties, for example scratch resistance and easy (or self) cleaning characteristics.

The results of the tests surprised researchers from Empa and other consortium members (from the press release),

Bernd Nowack, head of Empa’s Environmental Risk Assessment and Management group, then presented the results of the investigations into how much nanomaterial is set free from façades. The release rate is generally very low – only 1 to 2% of the nanoparticles find their way into the environment. And in most cases they are released not as nanoparticles but bound to large paint particles, which significantly reduces their nano-scale effects. “We were very surprised at how few nanoparticles were actually set free”, Nowack admitted. The researchers had expected that the catalytically active nanoparticles would also attack the paint surrounding them, leading to more frequent release.

Jean–Pierre Kaiser showed by means of his toxicological studies that paints containing nanoparticles have the same effect on the behaviour of cells from the gastrointestinal tract and immune system as do similar paints which do not contain nanoparticles. The Empa researcher does not therefore expect that these nanoparticle-containing paints will represent a new, acute health risk. However, the investigations did at the same time show that nanoparticles are absorbed by the cells. Whether this accumulation of nanoparticles in the cells might lead to longer-term effects cannot yet be definitively determined.

Empa environmental scientist Roland Hischier made a plea for a reasonable balance in the assessment of the possible environmental damage. For a house with an assumed lifetime of eighty years, painting the façade with nanomaterial based paint would be more economic if this lasted for 30% longer than conventional coatings. Then, over the lifetime of the house, one would have to repaint the façade one time fewer, avoiding all the environmental effects caused by manufacturing the paint and disposing of the leftover material.

This theory remains somewhat controversial however –houses are frequently repainted for aesthetic reasons and not because a new coating is strictly necessary. In this case the advantage offered by the longer lifetime of nanoparticle-based coatings becomes completely irrelevant.

The researchers performed an industry survey revealing what professional paint companies believe to be true about nanoparticles in paint (from the press release),

… Ingrid Hincapie, a risk researcher on the Empa staff, reported on the results of her industrial survey. Many companies expected paint containing nanoparticles to have a longer lifetime than conventional paint. Some expected it to be easy to handle, for example because it dries faster. But exactly how one correctly disposes of leftover paint containing nanoparticles is something that only a handful of respondents knew.

Peter Seehafer of the Painter’s and Plasterer’s Association, gave the view from the sharp end, where quite simply the customer is king, and sometimes demands the latest in paint technology. On the other hand, about half of all painters are female, so protection from possibly unhealthy chemicals is therefore particularly important. “Our professional association needs more information, so that we can take up a clear position with respect to our customers and our employees”, demanded Seehafer.

Finally, André Hauser of the Swiss Federal Office of the Environment explained the current regulations covering the disposal of waste material containing nanoparticles. On its website www.bafu.admin.ch/abfall/01472/12850 the SFOE offers tips on how to dispose of such material properly. The current regulations relating to safe working practices with nanomaterials were explained by Kaspar Schmid of the Swiss government’s State Secretariat for Economic Affairs (SECO). The essential point here is that the manufacturer of the material must provide a Material Safety Data Sheet, as is the case with other chemicals.

In addition to the NanoHouse link given earlier, there is this Empa NanoHouse webpage which provides more information about the work including the survey of nanopaint producers from the project’s Survey webpage,

A survey of industrial producers of nanoparticles and paints showed that the most mentioned potential benefits of nano-enhanced façade coatings are: water and dirt repellent “easy to clean”, followed by UV-protection, antimicrobial resistance and protection from mechanical wear (i.e. scratch resistance). The ENP [engineered nanopartilces], which are the most used in Europe to improve the different functionalities of the façade coatings were: Ag [silver], functionalised silanes, TiO2  [titanium dioxide] and SiO2.[silicon dioxide]

The quality of a nano-paint compared to a traditional paint could be gradually (25% of responses) and noticeably (25%) improved, but 50% of the respondents reported no functionality improvement. The companies gave relevance on studies from the specialised press (90%), on participating in dialogue events (80%) (e.g. with authorities or taking part in projects such as NanoHouse), on getting expert opinions (70%) and on toxicology test (20%).

The overall impression from the survey was that improvement of the environmental performance seems not yet to be in the focus of innovation of ENP in façade coatings.

It’s a bit disappointing that the environmental performance of nanocoatings does not, according to this project’s findings, does not live up to the promises made by the various purveyors of nanotechnology-enabled paint.

 

Czech veterinary research institute tracks nanoparticles

When I first saw the Jan. 7, 2014 news item on Azonano, I was expecting to see some cute animal images mixed with the ‘nano’ talk. While there’s no mild amusement to be had, there is plenty of ‘nano’ talk concerning the work being done at the Veterinary Research Institute (Brno,  Czech republic) on characterizing nanoparticles using some new equipment (Note: Links have been removed),

Malvern [which owns the company, NanoSight] reports on how NanoSight’s Nanoparticle Tracking Analysis, NTA, is being applied in the Veterinary Research Institute, Brno, Czech Republic in the research group of Dr. Jaroslav Turanek in the Department of Pharmacology and Immunotherapy).

The central theme of Dr. Jaroslav Turanek’s research group (Department of Pharmacology and Immunotherapy) at the Veterinary Research Institute in Brno is to apply synthetic and bioorganic chemistry. This work is performed in collaboration with King’s College London and the Institute of Organic Chemistry and Biochemistry, Prague, for the design and construction of therapeutic nanoparticles to develop drug delivery systems (anticancer and antiviral drugs) and nanocarriers for construction of recombinant vaccines.

In parallel, the research group of Dr. Miroslav Machala (Department of Chemistry and Toxicology) at Veterinary Research Institute focuses upon environmental nanoparticulate pollutants. Characterization of airborne particles is conducted using electron microscopy, but in vitro tests on cell culture require knowledge of the real structure of nanoparticles in the tissue culture medium (e.g. aggregation). This enables the group to draw the correct conclusions from in vitro toxicological experiments which can be affected by differences in local nanoparticle concentration owing to sedimentation. Detailed particle distribution and kinetics of aggregation in this heterogeneous system is impossible to obtain using electron microscopy and hence Nanoparticle Tracking Analysis, NTA, is the method of choice. It is noted that some metastable aggregates can disaggregate due to high dilution of the sample required for NTA analysis. For this reason, Dynamic Light Scattering, DLS, and NTA are used as suitable complementary methods in the laboratory.

The Jan. 7, 2014 Malvern Instruments press release on biospace.com, which originated the news item, provides a quote from Dr. Jaroslav Turanek’ describing the NTA system,

Explaining their choice of NanoSight, Dr Turanek said “We chose NTA as a convenient and rapid method for characterization of nanoparticles in heterogeneous preparations like liposomes and their complexes with proteins, DNA and polysaccharides. A set of these techniques is used for the complex characterization of the structure of the nanoparticles, the kinetics of their preparation, the dynamics of morphological transformation and, finally, their stability. NTA perfectly fits our needs and has become a standard method in our methodological portfolio. The most advantageous feature of NTA is that it makes it possible to visualize each nanoparticle and then to obtain more detailed size distributions based on individual particle measurements. DLS is used as precise complementary method for the characterization of nanoparticles below 20 nm for proteins and other biopolymers. Combination of these two methods, NTA and DLS, with separation methods (GPC, FFF) and electron microscopy is preferred to get the full insight to structure and dynamics of nanoparticles in our sample systems.”

It took me quite a while to realize that nanoparticles in a sample are not necessarily homogenous, i.e., similar in size, etc. Unconsciously, I had applied my notions of manufacturing where items are made (stamped, poured into moulds, etc.)  to be identical. As far as I’m aware there is no such production process for nanoparticles which makes characterizing them an important task if the purpose is to better understand their properties.

You can find out more about Malvern Instruments here and about NanoSight here.

Naimor: innovative nanostructured material for water remediation and oil recovery (crowdfunding project)

The NAIMOR crowdfunding project on indiegogo might be of particular interest to those of us on the West Coast of Canada where there is much talk about a project to create twin pipelines (Enbridge Northern Gateway Pipelines) between the provinces of  Alberta and British Columbia to export oil and import natural gas. The oil will be shipped to Asia by tanker and presumably so will the natural gas. In all the discussion about possible environmental disasters, I haven’t seen any substantive mention of remediation efforts or research to improve the technologies associated with environmental cleanups (remediation of water, soil, and/or air). At any rate, all this talk about the pipelines and oil tankers along Canada’s West Coast brought to mind the BP oil spill, aka the Deepwater Horizon oil spill, from the Wikipedia essay (Note: Links have been removed),

The Deepwater Horizon oil spill (also referred to as the BP oil spill, the BP oil disaster, the Gulf of Mexico oil spill, and the Macondo blowout) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. It claimed eleven lives[5][6][7][8] and is considered the largest accidental marine oil spill in the history of the petroleum industry, an estimated 8% to 31% larger in volume than the previously largest, the Ixtoc I oil spill. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010.[7][9] The total discharge has been estimated at 4.9 million barrels (210 million US gal; 780,000 m3).[3]

A massive response ensued to protect beaches, wetlands and estuaries from the spreading oil utilizing skimmer ships, floating booms, controlled burns and 1.84 million US gallons (7,000 m3) of Corexit oil dispersant.[10] After several failed efforts to contain the flow, the well was declared sealed on 19 September 2010.[11] Some reports indicate the well site continues to leak.[12][13] Due to the months-long spill, along with adverse effects from the response and cleanup activities, extensive damage to marine and wildlife habitats, fishing and tourism industries, and human health problems have continued through 2013.[14][15] Three years after the spill, tar balls could still be found on the Mississippi coast.[16] In July 2013, the discovery of a 40,000 pound tar mat near East Grand Terre, Louisiana prompted the closure of waters to commercial fishing.[17][18]

While Canada’s Northern Gateway project does not include any plans for ocean oil rigs, there is still the potential for massive spills either from the tankers or the pipelines. For those old enough to remember or those interested in history, this latest project raises the spectre of the Exxon Valdes oil spill, from the Wikipedia essay (Note: Links have been removed),

The Exxon Valdez oil spill occurred in Prince William Sound, Alaska, on March 24, 1989, when Exxon Valdez, an oil tanker bound for Long Beach, California, struck Prince William Sound’s Bligh Reef at 12:04 a.m.[1] local time and spilled 260,000 to 750,000 barrels (41,000 to 119,000 m3) of crude oil[2][3] over the next few days. It is considered to be one of the most devastating human-caused environmental disasters.[4] The Valdez spill was the largest ever in US waters until the 2010 Deepwater Horizon oil spill, in terms of volume released.[5]  [emphasis mine] However, Prince William Sound’s remote location, accessible only by helicopter, plane, or boat, made government and industry response efforts difficult and severely taxed existing plans for response. The region is a habitat for salmon, sea otters, seals and seabirds. The oil, originally extracted at the Prudhoe Bay oil field, eventually covered 1,300 miles (2,100 km) of coastline,[6] and 11,000 square miles (28,000 km2) of ocean.[7] Exxon’s CEO, Lawrence Rawl, shaped the company’s response.[8]

Some of that ‘difficult to reach’ coastline and habitat was Canadian (province of British Columbia). Astonishingly, given the 20 year gap between the Exxon Valdes spill and the Deepwater Horizon spill, the technology for remediation and cleanup had not changed much, although it seems that the measure used to stop the oil spill were even older, from my June 4, 2010 posting,

I found a couple more comments relating to the BP oil spill  in the Gulf. Pasco Phronesis offers this May 30, 2010 blog post, Cleaning With Old Technology, where the blogger, Dave Bruggeman, asks why there haven’t been any substantive improvements to the technology used for clean up,

The relatively ineffective measures have changed little since the last major Gulf of Mexico spill, the Ixtoc spill in 1979. While BP has solicited for other solutions to the problem (Ixtoc was eventually sealed with cement and relief wells after nine months), they appear to have been slow to use them.

It is a bit puzzling to me why extraction technology has improved but cleanup technology has not.

An excellent question.

I commented a while back (here) about another piece of nano reporting form Andrew Schneider. Since then, Dexter Johnson at Nanoclast has offered some additional thoughts (independent of reading Andrew Maynard’s 2020 Science post) about the Schneider report regarding ‘nanodispersants’ in the Gulf. From Dexter’s post,

Now as to the efficacy or dangers of the dispersant, I have to concur that it [nanodispersant] has not been tested. But it seems that the studies on the 118 oil-controlling products that have been approved for use by the EPA are lacking in some details as well. These chemicals were approved so long ago in some cases that the EPA has not been able to verify the accuracy of their toxicity data, and so far BP has dropped over a million gallons of this stuff into the Gulf.

Point well taken.

In looking at this website: gatewayfacts.ca, it seems the proponents for the Enbridge Northern Gateway project have supplied some additional information. Here’s what they’ve supplied regarding the project’s spill response (from the Gateway Facts environmental-responsibility/marine-protection page),

A spill response capacity 3x better than required

Emergency response equipment, crews and training staff will be stationed at key points and communities along the marine routes.

I did find a bit more on the website’s What if? page,

Marine response in action

Our spill response capacity will be more than 3x the current Canadian regulation. In addition, tanker escort tugs will carry emergency response and firefighting equipment to be able to respond immediately.

I don’t feel that any real concerns have been addressed by this minimalist approach to communication. Here are some of my questions,

  • What does 3x the current Canadian regulation mean in practical terms and how does this compare with the best safety regulations from an international perspective? Will there be efforts at continuous improvement?
  • Are there going to be any audits by outside parties of the company’s emergency response during the life of the project?
  • How will those audits be conducted? i.e., Will there be notice or are inspectors likely to spring the occasional surprise inspection?
  • What technologies are the proponents planning to use for the cleanup?
  • Is there any research being conducted on new remediation and cleanup technologies?
  • How much money is being devoted to this research and where is it being conducted (university labs, company labs, which countries)?

In light of concerns about environmental remediation technologies, it’s heartening to see this project on indiegogo which according to a Dec. 27, 2013 news item on Nanowerk focuses on an improved approach to remediation for water contaminated by oil,,

Environmental oil spill disasters such as BP’s Deepwater Horizon oil rig in the Gulf of Mexico have enormous environmental consequences, leading to the killing of marine creatures and contamination of natural water streams, storm water systems or even drinking water supplies. Emergency management organizations must be ready to confront such turbulences with effective and eco-friendly solutions to minimize the short term or long term issues.

There are many ineffective and costly conventional technologies for the remedy of oil spills like using of dispersants, oil skimmers, sand barrier berms, oil containment booms, by controlled burning of surface oil, bioremediation and natural degradation.

NAIMOR® – NAnostructure Innovative Material for Oil Recovery – is a three dimensional, nanostructure carbon material that can be produced in different shapes, dimensions. It is highly hydrophobic and can absorb a quantity of oil around 150 times its weight. Light, strong, and flexible, the material can be reused many times without losing its absorption capacity.

I’m not familiar with the researcher who’s making this proposal so I can’t comment on the legitimacy of the project but this does look promising (I have heard of other similar research using carbon-based materials), from the Naimor campaign on indiegogo,

Ivano Aglietto, an Italian engineer with a PhD in Environmental Engineering has devoted his profession for the production of most advanced and innovative nanostructure carbon materials and the industrial development of their proper use in applications for the environmental remediation.

His first invention was RECAM® (REactive Carbon Material), a revolutionary solution for oil spill recovery which had shown extraordinary results but with limitations of usage.

RECAM® is inert, non toxic, regenerable, reusable, eco friendly material and can absorb oil 90 times its weight. It is ferromagnetic in nature and can be recovered from water using magnetic field. The hydrocarbons absorbed can be burnt inorder to reuse the material and no toxic gases are released because of its inert and non-flammable nature. Their is also possibility of extracting the absorbed oil by squeezing the material or by vacuum filtration. Oil recovered does not contain any water because of the hydrophobic behaviour of RECAM®. Recovered oil can be reused as resource and the RECAM® for recovering oil. RECAM® is used for oil spill remediation and successfully passed the Artemia test.

RECAM® is being replaced with his new innovative nanostructure material, NAIMOR®.

NAIMOR® (NAnostructure Innovative Material for Oil Recovery) is a nanostructure material that can be produced in different shapes and dimensions with an incredible efficiency for oil recovery.

Main Characteristics and Properties

Can absorb quantity of oil 150 times its weight.
Inert, made of pure carbon, environmental friendly and no chemicals involved.
Highly hydrophobic and the absorbed oil does not contain any water.
Regenerable and can be used several times without producing any wastes.
It is a three dimensional nanostructure and can be produced in different shapes, dimensions [carpets, booms, sheets'.
Capable of recovering gallons of oil depending on the shape and dimensions of the carpet.

This indiegogo campaign is almost the antithesis of the gatewayfacts.ca website offering a wealth of information and detail including a discussion about the weaknesses associated with the various cleanup technologies that represent the 'state of the art'. Here's an image from the Naimor campaign page,

[downloaded from http://www.indiegogo.com/projects/naimor-nanostructure-innovative-material-for-oil-recovery]

[downloaded from http://www.indiegogo.com/projects/naimor-nanostructure-innovative-material-for-oil-recovery]

I believe this is a pelican somewhere on the Gulf of Mexico coastline where it was affected by the 2010 Deepwater Horizon oil spill. As for Aglietto’s project, you can find the NAIMOR website here.

Foam glass manufacturing facility commissioned in Russia’s Kaluga region

A Dec. 27, 2013 news item on Azlonano features RUSNANO and a foam glass facility in Russia,

On December 20 [2013], Russia’s first and Europe’s major technological complex for the production of foam glass ICM Glass Kaluga, of the project company Rusnano, was commissioned in the industrial park Borovskoye. The ceremony was attended by the Kaluga Region’s Governor Anatoly Artamonov and chairman of Rusnano’s board Anatoly Chubais.

The facility is aimed at hi-tech production of construction materials from foam glass. Broken glass is used as the raw material, which enables effective recycling of solid household rubbish. The complex’s planned capacity is 300,000 cubic metres a year to be achieved by the facility’s 50 employees. The agreed total budget exceeds 1.8 billion roubles ($54 million).

I found more information about the new facility in a Dec.20, 2013 press release (machine translation of Russian into English) here: http://www.newportal.admoblkaluga.ru/main/news/events/detail.php?ID=153747, (I think this is a portal for the Kaluga region)

December 20 [2013] in the industrial park “Vorsino” Borovsky District hosted a ceremony industrial launch of the first in Russia and the largest in Europe and technological complex for the production of crushed stone penostekolnogo LLC “AySiEm Glass Kaluga” – the project company “RUSNANO”. It was attended by Governor Anatoly Artamonov and delegation “RUSNANO” headed by the chairman of the state corporation Anatoly Chubais.

Taken at the enterprise high-tech production of construction material of foamed glass. Feedstock is usual broken glass that facilitates efficient processing of municipal solid waste. The design capacity of the complex is 300 thousand cubic meters per year, the staff – 50 people. The total budget of the project is determined in the amount of more than 1.8 billion rubles.

Talking about the significance of the event, Anatoly Artamonov emphasized perspective of further business cooperation with the State Corporation “Rusnano”. “Our cooperation – an important milestone in the economic development of the Kaluga region, because we have chosen an innovative way and are committed to increase the share of high-tech products”, – assured the governor.

Chairman of the Board of the Civil Code “RUSNANO” Anatoly Chubais also expressed readiness to support the business activities of the Kaluga region. “Today, in the region we run two joint projects. The plans of two more – in the production of innovative pharmaceuticals – with a complete cycle from design to sales. They invested 8 billion rubles, plan – and another 10 billion, “- he said.

On the same day in the office «Freight Village Kaluga» held a meeting at which the parties discussed the details of future cooperation. In order to continue business contacts “RUSNANO” Fund for Infrastructure and Educational Programs with Government organizations and the Kaluga region Anatoly Chubais Anatoly Artamonov and signed the final protocol. The main outcome of the meeting was a joint decision on the establishment of nanotechnology center in Obninsk, which will bring together teams of scientists and professionals working in the field of nanotechnology. Thus, according to Anatoly Chubais, “Kaluga region will be the region, opening a” second wave “nanocenters.”

Reference: In the current year, the regional government in conjunction with the Fund for Infrastructure and Educational Programs of the state corporation “RUSNANO” program was launched to stimulate demand for nanotech products. It provides for the inclusion of 10 per cent of innovation, including nanotechnology products in state and municipal orders. In 2014, with the support of the corporation “RUSNANO” in the region plans to build the center positron emission tomography, “PET-Center”, which will bring a new level not only a primary diagnosis of cancer, but also to monitor the dynamics of the disease, to evaluate the effectiveness of the treatment.

For the curious, here’s more information about foam glass on the ENCO Engineering website,

Foamed glass grain as described in the following is an excellent bulk material for civil construction and insulation purposes. It is a lightweight, extremely fine-pored expanded glass with millions of hermetically sealed pores. Since no diffusion can take place, the material is watertight and achieves an efficient barrier against soil humidity.

Besides the outstanding mechanical and thermal properties of the product, foamed glass manufacture is an exemplary process for waste recycling on an industrial basis. Foam glass can be manufactured fully out of waste glass, with only a minimum of virgin additives.

Foamed glass grain is the product of choice wherever a finely grained, free-flowing bulk material is required. It is especially suitable for thin-walled thermal insulations, such as for window frames, cement bricks and insulating plasters.

ENCO Engineering is a Swiss chemical engineering and consultancy according to the information on the company website’s homepage.

NanoStruck, an Ontario (Canada) water remediation and ‘mining’ company

Located in Mississauga, Ontario (Canada), Nanostruck’s Dec. 20, 2013 news release seems to be functioning as an announcement of its presence rather than any specific company developments,

NanoStruck has a suite of technologies that remove molecular sized particles using patented absorptive organic polymers. The company is sitting on some very incredible and environmently friendly technology.

Organic polymers are nature’s very own sponges. These versatile biomaterials are derived from crustacean shells or plant fibers, depending on requirements of their usage. Acting as molecular sponges, the nanometer-sized polymers are custom programmed toabsorb specific particles for remediation or retrieval purposes. These could be to clean out acids, hydrocarbons, pathogens, oils and toxins in water via its NanoPure solutions. Or to recover precious metal particles in mine tailings, such as gold, silver, platinum, palladium and rhodium using the Company’s NanoMet solutions.

By using patented modifications to conventional technologies and adding polymer-based nano-filtration, the Company’s offers environmentally safe NanoPure solutions for water purification. The Company uses Environmental Protection Agency (EPA) and World Health Organization (WHO) guidelines as a benchmark for water quality and safety to conform to acceptable agricultural or drinking water standards in jurisdictions where the technology is used. The worldwide shortage of cleanwater is highlighted on sites such as http://water.org/water-crisis/water-facts/water/.

The company’s NanoPure technology was first deployed to treat wastewater from a landfill site in January 2012 in Mexico. It has since been successfully treating and producing clean water there that’s certified by Conagua, the federal water commission of Mexico. The company has also created water treatment plants in Canada 

Additionally, the Company’s technology can be used to recover precious and base metals from mine tailings, which are the residual material from earlier mining activities. By retrieving valuable metals from old tailing dumps, the Company’s NanoMet solutions boosts the value of existing mining assets and reduces the need for new, costly and potentially environmentally harmful exploration and mining. 

There is an estimated $1 trillion worth of precious metals already extracted from the ground sitting in old mining sites that form our target market. We are in the process of deploying precious metal recovery plants in South Africa, Mexico and Canada.

The company is also developing new plant-based organic polymers to remove contaminants specific to the oil industry, such as naphthenic acids, which is a growing problem.

 Company information is available at www.nanostruck.ca and some description of the companies polymers are below

General Description of Nano Filtration Materials

Chitosan is a polysaccharide-based biomaterial derived from renewable feedstock such as the shells of crustaceans.  Chitosan displays limited adsorbent properties toward various types of contaminants (i.e. petrochemicals, pharmaceuticals, & agrochemicals).  By comparison, synthetically engineered biomaterials that utilize chitosan building blocks display remarkable sorption properties that are tunable toward various types of water borne contaminants.  Recent advances in materials science have enabled the development of Nano Filtration media with relative ease, low toxicity, and tunable molecular properties for a wide range of environmental remediation applications.  …

From what I can tell, the company has technology that can be used to remediate water (NanoPure) and, in the case of remediating mine tailings (NanoMet), allows for reclamation of the metals. It’s the kind of technology that can make you feel virtuous (reclaiming water) with the potential of paying you handsomely (reclaiming gold, etc.).

As I like to do from time to time, I followed the link to the water organization listed in the news release and found this on Water.org’s About Us page,

The water and sanitation problem in the developing world is far too big for charity alone. We are driving the water sector for new solutions, new financing models, greater transparency, and real partnerships to create lasting change. Our vision: Safe water and the dignity of a toilet for all, in our lifetime.

Co-founded by Matt Damon and Gary White, Water.org is a nonprofit organization that has transformed hundreds of communities in Africa, South Asia, and Central America by providing access to safe water and sanitation.

Water.org traces its roots back to the founding of WaterPartners International in 1990. In July 2009, WaterPartners merged with H2O Africa, resulting in the launch of Water.org. Water.org works with local partners to deliver innovative solutions for long-term success. Its microfinance-based WaterCredit Initiative is pioneering sustainable giving in the sector.

Getting back to NanoStruck, here’s more from their About page,

NanoStruck Technologies Inc. is a Canadian Company with a suite of technologies that remove molecular sized particles using patented absorptive organic polymers. These versatile biomaterials are derived from crustacean shells or plant fibers, depending on requirements of their usage. Acting as molecular sponges, the nanometer-sized polymers are custom programmed toabsorb specific particles for remediation or retrieval purposes. These could be to clean out acids, hydrocarbons, pathogens, oils and toxins in water via its NanoPure solutions. Or to recover precious metal particles in mine tailings, such as gold, silver, platinum, palladium and rhodium using the Company’s NanoMet solutions.

By using patented modifications to conventional technologies and adding polymer-based nano-filtration, the Company’s offers environmentally safe NanoPure solutions for water purification. The Company uses Environmental Protection Agency (EPA) and World Health Organization (WHO) guidelines as a benchmark for water quality and safety to conform to acceptable agricultural or drinking water standards in jurisdictions where the technology is used.

The Company’s current business model is based on either selling water remediation plants or leasing out units and charging customers on a price per liter basis with a negotiated minimum payment per annum. For processing mine tailings, the value of precious metal recovered is shared with tailing site owners on a pre-agreed basis.

I wonder if there are any research papers about the January 2012 work in Mexico. I find there is a dearth of technical information on the company’s website, which is somewhat unusual for a startup company (my experience is that they give you too much technical information in a fashion that is incomprehensible to anyone other than en expert). As well, I’m not familiar with any members of the company’s management team (Our Team webpage) but, surprisingly, there isn’t a Chief Science Officer or someone on the team from the science community. In fact, the entire team seems to have emerged from the business community. If I have time, I’ll see about getting an interview for publication here in 2014. In the meantime, it looks like a company with some interesting potential and I wish it well.

(Note: This is not endorsement or anti-endorsement of the company or its business. This is not my area of expertise.)

Green chemistry and zinc oxide nanoparticles from Iran (plus some unhappy scoop about Elsevier and access)

It’s been a while since I’ve featured any research from Iran partly due to the fact that I find the information disappointingly scant. While the Dec. 22, 2013 news item on Nanowerk doesn’t provide quite as much detail as I’d like it does shine a light on an aspect of Iranian nanotechnology research that I haven’t previously encountered, green chemistry (Note: A link has been removed),

Researchers used a simple and eco-friendly method to produce homogenous zinc oxide (ZnO) nanoparticles with various applications in medical industries due to their photocatalytic and antibacterial properties (“Sol–gel synthesis, characterization, and neurotoxicity effect of zinc oxide nanoparticles using gum tragacanth”).

Zinc oxide nanoparticles have numerous applications, among which mention can be made of photocatalytic issues, piezoelectric devices, synthesis of pigments, chemical sensors, drug carriers in targeted drug delivery, and the production of cosmetics such as sunscreen lotions.

The Dec. 22, 2013 Iran Nanotechnology Initiative Council (INIC) news release, which originated the news item, provides a bit more detail (Note: Links have been removed),

By using natural materials found in the geography of Iran and through sol-gel technique, the researchers synthesized zinc oxide nanoparticles in various sizes. To this end, they used zinc nitrate hexahydrate and gum tragacanth obtained from the Northern parts of Khorassan Razavi Province as the zinc-providing source and the agent to control the size of particles in aqueous solution, respectively.

Among the most important characteristics of the synthesis method, mention can be made of its simplicity, the use of cost-effective materials, conservation of green chemistry principals to prevent the use of hazardous materials to human safety and environment, production of nanoparticles in homogeneous size and with high efficiency, and most important of all, the use of native materials that are only found in Iran and its introduction to the world.

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

Sol–gel synthesis, characterization, and neurotoxicity effect of zinc oxide nanoparticles using gum tragacanth by Majid Darroudi, Zahra Sabouri, Reza Kazemi Oskuee, Ali Khorsand Zak, Hadi Kargar, and Mohamad Hasnul Naim Abd Hamidf. Ceramics International, Volume 39, Issue 8, December 2013, Pages 9195–9199

There’s a bit more technical information in the paper’s abstract,

The use of plant extract in the synthesis of nanomaterials can be a cost effective and eco-friendly approach. In this work we report the “green” and biosynthesis of zinc oxide nanoparticles (ZnO-NPs) using gum tragacanth. Spherical ZnO-NPs were synthesized at different calcination temperatures. Transmission electron microscopy (TEM) imaging showed the formation most of nanoparticles in the size range of below 50 nm. The powder X-ray diffraction (PXRD) analysis revealed wurtzite hexagonal ZnO with preferential orientation in (101) reflection plane. In vitro cytotoxicity studies on neuro2A cells showed a dose dependent toxicity with non-toxic effect of concentration below 2 µg/mL. The synthesized ZnO-NPs using gum tragacanth were found to be comparable to those obtained from conventional reduction methods using hazardous polymers or surfactants and this method can be an excellent alternative for the synthesis of ZnO-NPs using biomaterials.

I was not able to find the DOI (digital object identifier) and this paper is behind a paywall.

Elsevier and access

On a final note, Elsevier, the company that publishes Ceramics International and many other journals, is arousing some ire with what appears to be its latest policies concerning access according to a Dec. 20, 2013 posting by Mike Masnick for Techdirt Note: Links have been removed),

We just recently wrote about the terrible anti-science/anti-knowledge/anti-learning decision by publishing giant Elsevier to demand that Academia.edu take down copies of journal articles that were submitted directly by the authors, as Elsevier wished to lock all that knowledge (much of it taxpayer funded) in its ridiculously expensive journals. Mike Taylor now alerts us that Elsevier is actually going even further in its war on access to knowledge. Some might argue that Elsevier was okay in going after a “central repository” like Academia.edu, but at least it wasn’t going directly after academics who were posting pdfs of their own research on their own websites. While some more enlightened publishers explicitly allow this, many (including Elsevier) technically do not allow it, but have always looked the other way when authors post their own papers.

That’s now changed. As Taylor highlights, the University of Calgary sent a letter to its staff saying that a company “representing” Elsevier, was demanding that they take down all such articles on the University’s network.

While I do feature the topic of open access and other issues with intellectual property from time to time, you’ll find Masnick’s insights and those of his colleagues are those of people who are more intimately familiar (albeit firmly committed to open access) with the issues should you choose to read his Dec. 20, 2013 posting in its entirely.

Stabilizing or destabilitizing gold nanoparticles

Every once in a while I stumble across a ‘nanotechnology’ news release from Oregon (either Oregon State University or the University of Oregon) and as I recall it’s always environment-focused. The latest in an almost complete change-of-pace is, a Dec. 9, 2013 University of Oregon news release (also on EurekAlert) profiling some work on gold nanoparticles and nanoelectronics,

University 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, or to design them so they readily condense into thin films for such things as inks or catalysts in electronic or solar devices.

The news release goes on to detail the work,

They focused on nanoparticles less than two nanometers in diameter — the smallest studied to date — to better understand structural stability of these tiny particles being engineered for use in electronics, medicine and other materials. Whether a nanoparticle needs to remain stable or condense depends on how they are being used. Those used as catalysts in industrial chemical processing or quantum dots for lighting need to remain intact; if they are precursors for coatings in solar devices or for printing ink, nanoparticles need to be unstable so they sinter and condense into a thin mass.

For their experiments, Smith and Hutchison produced gold nanoparticles in four well-controlled sizes, ranging from 0.9 nanometers to 1.5 nanometers, and analyzed ligand loss and sintering with thermogravimetric analysis and differential scanning calorimetry, and examined the resulting films by scanning electron microscopy and X-ray photoelectron spectroscopy. As the nanoparticles were heated at 5 degrees Celsius per minute, from room temperature to 600 degrees Celsius, the nanoparticles began to transform near 150 degrees Celsius.

The researchers found that smaller nanoparticles have better structural integrity than larger-sized particles that have been tested. In other words, Hutchison said, they are less likely to lose their ligands and bind together. “If you have unstable particles, then the property you want is fleeting,” he said. “Either the light emission degrades over time and you’re done, or the metal becomes inactive and you’re done. In that case, you want to preserve the function and keep the particles from aggregating.”The opposite is desired for Hutchison and others working in the National Science Foundation-funded Center for Sustainable Materials Chemistry, a multi-universities collaboration led by the UO and Oregon State University. Researchers there are synthesizing nanoparticles as precursors for thin films.

“We want solution precursors that can lead to inorganic thin films for use in electronics and solar industries,” said Hutchison, who also is a member of the UO Materials Science Institute.

“In this case, we want to know how to keep our nanoparticles or other precursors stable enough in solution so that we can work with them, using just a tiny amount of additional energy to make them unstable so that they condense into a film — where the property that you want comes from the extended solid that is generated, not from the nanoparticles themselves.”

The research, Hutchison said, identified weak sites on nanoparticles where ligands might pop off. If only a small amount do so, he said, separate nanoparticles are more likely to come together and begin the sintering process to create thin films.

“That’s a really stabilizing effect that, in turn, kicks out all these ligands on the outside,” he said. “The surface area decreases quickly and the particles get bigger, but now all the extra ligands gets excluded into the film and then, over time, the ligands vaporize and go away.”

The coming apart, however, is a “catastrophic failure” if protecting against sintering is the goal. It may be possible to use the findings, he said, to explore ways to strengthen nanoparticles, such as developing ligands that bind in at least two sites or avoiding volatile ligands.

The process, as studied, produced porous gold films. “A next step might be to study how to manipulate the process to get a more dense film if that is desired,” Hutchison said. Understanding how nanoparticles respond to certain conditions, such as changing temperatures, he added, may help researchers reduce waste in the manufacturing process.

As I hinted earlier, this work retains an ‘environment focus’,

“Researchers at the University of Oregon are re-engineering the science, manufacturing and business processes behind critical products,” said Kimberly Andrews Espy, vice president for research and innovation and dean of the UO Graduate School. “This research analyzing the structural stability of nanoparticles by Dr. Hutchison and his team has the potential to improve the engineering of electronics, medicine and other materials, helping to foster a sustainable future for our planet and its people.” [emphasis mine]

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

Transformations during Sintering of Small (Dcore < 2 nm) Ligand-Stabilized Gold Nanoparticles: Influence of Ligand Functionality and Core Size by Beverly L. Smith and James E. Hutchison. J. Phys. Chem. C, 2013, 117 (47), pp 25127–25137 DOI: 10.1021/jp408111v Publication Date (Web): October 24, 2013
Copyright © 2013 American Chemical Society

This paper is behind a paywall.