Category Archives: forestry

Cellulose nanocrystals (CNC), also known as nanocrystalline cellulose (NCC), and toxicity; some Celluforce news; anti-petroleum extremists

The February 2015 issue of Industrial Biotechnology is hosting a special in depth research section on the topic of cellulose nanotechnology. A Feb. 19, 2015 news item on Phys.org features a specific article in the special section (Note: A link has been removed),

Novel nanomaterials derived from cellulose have many promising industrial applications, are biobased and biodegradable, and can be produced at relatively low cost. Their potential toxicity—whether ingested, inhaled, on contact with the skin, or on exposure to cells within the body—is a topic of intense discussion, and the latest evidence and insights on cellulose nanocrystal toxicity are presented in a Review article in Industrial Biotechnology.

Maren Roman, PhD, Virginia Tech, Blacksburg, VA, describes the preparation of cellulose nanocrystals (CNCs) and highlights the key factors that are an essential part of studies to assess the potential adverse health effects of CNCs by various types of exposure. In the article “Toxicity of Cellulose Nanocrystals: A Review” , Dr. Roman discusses the current literature on the pulmonary, oral, dermal, and cytotoxicity of CNCs, provides an in-depth view on their effects on human health, and suggests areas for future research.

There has been much Canadian investment both federal and provincial in cellulose nanocrystals (CNC). There’s also been a fair degree of confusion regarding the name. In Canada, which was a research leader initially, it was called nanocrystalline cellulose (NCC) but over time a new term was coined cellulose nanocrystals (CNC). The new name was more in keeping with the naming conventions for other nanoscale cellulose materials such as  cellulose nanofibrils, etc. Hopefully, this confusion will resolve itself now that Celluforce, a Canadian company, has trademarked NCC. (More about Celluforce later in this post.)

Getting back to toxicity and CNC, here’s a link to and a citation for Maron’s research paper,

Toxicity of Cellulose Nanocrystals: A Review by Roman Maren. Industrial Biotechnology. February 2015, 11(1): 25-33. doi:10.1089/ind.2014.0024.

The article is open access at this time. For anyone who doesn’t have the time to read it, here’s the conclusion,

Current studies of the oral and dermal toxicity of CNCs have shown a lack of adverse health effects. The available studies, however, are still very limited in number (two oral toxicity studies and three dermal toxicity studies) and in the variety of tested CNC materials (CelluForce’s NCC). Additional oral and dermal toxicity studies are needed to support the general conclusion that CNCs are nontoxic upon ingestion or contact with the skin. Studies of pulmonary and cytotoxicity, on the other hand, have yielded discordant results. The questions of whether CNCs have adverse health effects on inhalation and whether they elicit inflammatory or oxidative stress responses at the cellular level therefore warrant further investigation. The toxicity of CNCs will depend strongly on their physicochemical properties—in particular, surface chemistry, including particle charge, and degree of aggregation, which determines particle shape and dimensions. Therefore, these properties—which in turn depend strongly on the cellulose source, CNC preparation procedure, and post-processing or sample preparation methods, such as lyophilization, aerosolization, sonication, or sterilization—need to be carefully measured in the final samples.

Another factor that might affect the outcomes of toxicity studies are sample contaminants, such as endotoxins or toxic chemical impurities. Samples for exposure tests should therefore be carefully analyzed for such contaminants prior to testing. Ideally, because detection of toxic chemical contaminants may be difficult, control experiments should be carried out with suitable blanks from which the CNCs have been removed, for example by membrane filtration. Moreover, especially in cytotoxicity assessments, the effect of CNCs on pH and their aggregation in the cell culture medium need to be monitored. Only by careful particle characterization and exclusion of interfering factors will we be able to develop a detailed understanding of the potential adverse health effects of CNCs.

If I understand this rightly, CNC seems safe (more or less) when ingested orally (food/drink) or applied to the skin (dermal application) but inhalation seems problematic and there are indications that this could lead to inflammation of lung cells. Other conclusions suggest both the source for the cellulose and CNC preparation may affect its toxicity. I encourage you to read the whole research paper as this author provides good explanations of the terms and summaries of previous research, as well as, some very well considered research.

Here’s more about Industrial Biotechnology’s special research section in the February 2015 issue, from a Feb. 19, 2015 Mary Ann Liebert publishers press release (also on EurekAlert*),

The article is part of an IB IN DEPTH special research section entitled “Cellulose Nanotechnology: Fundamentals and Applications,” led by Guest Editors Jose Moran-Mirabal, PhD and Emily Cranston, PhD, McMaster University, Hamilton, Canada. In addition to the Review article by Dr. Roman, the issue includes Reviews by M. Rose, M. Babi, and J. Moran-Mirabal (“The Study of Cellulose Structure and Depolymerization Through Single-Molecule Methods”) and by X.F. Zhao and W.T. Winter (“Cellulose/cellulose-based nanospheres: Perspectives and prospective”); Original Research articles by A. Rivkin, T. Abitbol, Y. Nevo, et al. (“Bionanocomposite films from resilin-CBD bound to cellulose nanocrystals), and P. Criado, C. Fraschini, S. Salmieri, et al. (“Evaluation of antioxidant cellulose nanocrystals and applications in gellan gum films”); and the Overview article “Cellulose Nanotechnology on the Rise,” by Drs. Moran-Mirabal and Cranston.

Meanwhile Celluforce announces a $4M ‘contribution’ from Sustainable Development Technology Canada (SDTC), from a Feb. 16, 2015 Celluforce news release,

CelluForce welcomes the announcement by Sustainable Development Technology Canada (SDTC) of a contribution of $4.0 million to optimize the extraction process of Nanocrystaline Cellulose (NCC) from dry wood pulp and develop applications for its use in the oil and gas sector. The announcement was made in Quebec City today [Feb. 16, 2015] by the Honourable Greg Rickford, Minister of Natural Resources and Minister for the Federal Economic Development Initiative for Northern Ontario.

NCC is a fundamental building block of trees that can be extracted from the forest biomass and has unique properties that offer a wide range of potential applications. Measured in units as small as nanometres, these tiny structures have strength properties comparable to steel and will have uses in a variety of industrial sectors. In particular, NCC is touted as having the potential to significantly advance the oil and gas industry.

Our Government is positioning Canada as a global leader in the clean technology sector by supporting innovative projects aimed at growing our economy while contributing to a cleaner environment,” said the Honourable Greg Rickford, Canada’s Minister of Natural Resources. [emphasis mine] “By developing our resources responsibly, exploring next-generation transportation and advancing clean energy technology, the projects announced today will create jobs and improve innovation opportunities in Quebec and across Canada.”

“World-class research led to the development of this ground breaking extraction process and placed Canada at the leading edge of NCC research”, stated René Goguen, Acting President of CelluForce Inc. “This announcement by SDTC sets the stage for the pre-commercial development of applications that will not only support Canada’s forest sector but also the oil and gas sector, both of which are important drivers of the Canadian economy.”

This project will further improve and optimize the process developed by CelluForce to extract nanocrystalline cellulose (CelluForce NCC™) from dry wood pulp. In addition to improving the extraction process, this project will investigate additional applications for the oil-and-gas industry such as cementing using this renewable forestry resource.

There’s very little information in this news release other than the fact that CelluForce’s $4M doesn’t need to be repaid seeing it’s described as a ‘contribution’ rather than an investment. The difference between a contribution and a grant, which is what these funds used to be called, somewhat mystifies me unless this is a translation issue.

As for the news release content, it is remarkably scant. This $4M will be spent on improving the extraction process and on applications for the oil and gas industry. Neither the improvements nor the possible applications are described. Hopefully, the government has some means of establishing whether or not those funds (sorry, the contribution) were used for the purposes described.

I am glad to see this in this news release, “Our Government is positioning Canada as a global leader in the clean technology sector …” although I’m not sure how it fits with recent attempts to brand environmentalists as part of an ‘anti-petroleum’ movement as described in a Feb. 19, 2015 post by Glyn Moody for Techdirt (Note: A link has been removed),

As Techdirt has been warning for some time, one of the dangers with the flood of “anti-terrorist” laws and powers is that they are easily redirected against other groups for very different purposes. A story in the Globe and Mail provides another chilling reminder of how that works:

The RCMP [Royal Canadian Mounted Police] has labelled the “anti-petroleum” movement as a growing and violent threat to Canada’s security, raising fears among environmentalists that they face increased surveillance, and possibly worse, under the Harper government’s new terrorism legislation.

As the Globe and Mail article makes clear, environmentalists are now being considered as part of an “anti-petroleum” movement. That’s not just some irrelevant rebranding: it means that new legislation supposedly targeting “terrorism” can be applied.

It seems logically incoherent to me that the government wants clean tech while condemning environmentalists. Whether or not you buy climate change science (for the record, I do), you have to admit that we are running out of petroleum. At heart, both the government and the environmentalists have to agree that we need new sources for fuel. It doesn’t make any sense to spend valuable money, time, and resources on pursuing environmentalists.

This business about the ‘anti-petroleum’ movement reminds me of a copyright kerfuffle including James Moore, currently the Minister of Industry, and writer Cory Doctorow. Moore, Minister of Canadian Heritage at the time, at some sort of public event, labeled Doctorow as a ‘radical extremist’ regarding his (Doctorow’s) views on copyright. The comments achieved notoriety when it appeared that Moore and the organizers denied the comments ever took place. The organizers seemed to have edited the offending video and Moore made public denials. You can read more about the incident in my June 25, 2010 post. Here’s an excerpt from the post which may explain why I feel there is a similarity,

… By simultaneously linking individuals who use violence to achieve their ends (the usual application for the term ‘radical extremists’) to individuals who are debating, discussing, and writing commentaries critical of your political aims you render the term into a joke and you minimize the violence associated with it.

Although with ‘anti-petroleum’, it seems they could decide any dissension is a form of violence. It should be noted that in Canada the Ministry of Industry, is tightly coupled with the Ministry of Natural Resources since the Canadian economy has been and continues to be largely resource-based.

For anyone interested in CelluForce and NCC/CNC, here’s a sampling of my previous posts on the topic,

CelluForce (nanocrystalline cellulose) plant opens (Dec. 15, 2011)

Double honours for NCC (ArboraNano and CelluForce recognized) (May 25, 2012)

You say nanocrystalline cellulose, I say cellulose nanocrystals; CelluForce at Japan conference and at UK conference (Oct. 15, 2012)

Designing nanocellulose (?) products in Finland; update on Canada’s CelluForce (Oct. 3, 2013) Note: CelluForce stopped producing NCC due to a growing stockpile.

There’s a lot more on the CNC blog should you care to search. One final note, I gather there’s a new interim boss at CelluForce, René Goguen replacing Jean Moreau.

* EurekAlert link added Feb. 20, 2015.

Commercializing cellulosic nanomaterials—a report from the US Dept. of Agriculture

Earlier this year in an April 10, 2014 post, I announced a then upcoming ‘nano commercialization’ workshop focused on cellulose nanomaterials in particular. While the report from the workshop, held in May, seems to have been published in August, news of its existence seems to have surfaced only now. From a Nov. 24, 2014 news item on Nanowerk (Note: A link has been removed),

The U.S. Forest Service has released a report that details the pathway to commercializing affordable, renewable, and biodegradable cellulose nanomaterials from trees. Cellulosic nanomaterials are tiny, naturally occurring structural building blocks and hold great promise for many new and improved commercial products. Commercializing these materials also has the potential to create hundreds of thousands of American jobs while helping to restore our nation’s forests.

“This report is yet another important step toward commercializing a material that can aid in restoring our nations’ forests, provide jobs, and improve products that make the lives of Americans better every day,” said U.S. Forest Service Chief Tom Tidwell. “The Forest Service plans to generate greater public and market awareness of the benefits and uses for these naturally-occurring nanomaterials.”

The report, titled “Cellulose Nanomaterials – A Path towards Commercialization” (pdf), is a result of a workshop held earlier this year that brought together a wide range of experts from industry, academia, and government to ensure that commercialization efforts are driven by market and user materials needs.

A Nov. 24, 2014 US Dept. of Agriculture news release (Note: The US Forest Service is a division of the US Dept. of Agriculture), which originated the news item, provides more detail about the reasons for holding the workshop (Note: A link has been removed),

Cellulose nanomaterials have the potential to add value to an array of new and improved products across a range of industries, including electronics, construction, food, energy, health care, automotive, aerospace, and defense, according to Ted Wegner, assistant director at the U.S. Forest Service Forest Products Laboratory in Madison, Wis.

“These environmentally friendly materials are extremely attractive because they have a unique combination of high strength, high stiffness, and light weight at what looks to be affordable prices,” Wegner explained. “Creating market pull for cellulose nanomaterials is critical to its commercialization.

The success of this commercialization effort is important to the U.S. Forest Service for another key reason: creating forests that are more resilient to disturbances through restorative actions. Removing excess biomass from overgrown forests and making it into higher value products like nanocellulose, is a win for the environment and for the economy.

“Finding high-value, high-volume uses for low-value materials is the key to successful forest restoration,” said Michael T. Rains, Director of the Northern Research Station and Forest Products Laboratory. “With about 400 million acres of America’s forests in need of some type of restorative action, finding markets for wood-based nanocellulose could have a huge impact on the economic viability of that work.”

The U.S. Forest Service, in collaboration with the U.S. National Nanotechnology Initiative, organized the workshop. Participants included over 130 stakeholders from large volume industrial users, specialty users, Federal Government agencies, academia, non-government organizations, cellulose nanomaterials manufactures and industry consultants. The workshop generated market-driven input in three areas: Opportunities for Commercialization, Barriers to Commercialization, and Research and Development Roles and Priorities. Issues identified by participants included the need for more data on materials properties, performance, and environmental, health, and safety implications and the need for a more aggressive U.S. response to opportunities for advancing and developing cellulose nanomaterial.

“The workshop was a great opportunity to get research ideas directly from the people who want to use the material,” says World Nieh, the U.S. Forest Service’s national program lead for forest products. “Getting the market perspective and finding out what barriers they have encountered is invaluable guidance for moving research in a direction that will bring cellulose nanomaterials into the marketplace for commercial use.”

The mission of the U.S. Forest Service, part U.S. Department of Agriculture, is to sustain the health, diversity and productivity of the nation’s forests and grasslands to meet the needs of present and future generations. The agency manages 193 million acres of public land, provides assistance to state and private landowners, and maintains the largest forestry research organization in the world. Public lands the Forest Service manages contribute more than $13 billion to the economy each year through visitor spending alone. Those same lands provide 20 percent of the nation’s clean water supply, a value estimated at $7.2 billion per year. The agency has either a direct or indirect role in stewardship of about 80 percent of the 850 million forested acres within the U.S., of which 100 million acres are urban forests where most Americans live.

The report titled, “Cellulose Nanomaterials – A Path towards Commercialization,” notes the situation from the US perspective (from p. 5 of the PDF report),

Despite great market potential, commercialization of cellulose nanomaterials in the United States is moving slowly. In contrast, foreign research, development, and deployment (RD&D) of cellulose nanomaterials has received significant governmental support through investments and coordination. [emphasis mine] U.S. RD&D activities have received much less government support and instead have relied on public-private partnerships and private sector investment. Without additional action to increase government investments and coordination, the United States could miss the window of opportunity for global leadership and end up being an “also ran” that has to import cellulose nanomaterials and products made by incorporating cellulose nanomaterials. If this happens, significant economic and social benefits would be lost. Accelerated commercialization for both the production and application of cellulose nanomaterials in a wide array of products is a critical national challenge.

I know the Canadian government has invested heavily in cellulose nanomaterials particularly in Québec (CelluForce, a DomTar and FPInnovations production facility for CNC [cellulose nanocrystals] also known as NCC [nanocrystalline cellulose]). There’s also some investment in Alberta (an unnamed CNC production facility) and Saskatchewan (Blue Goose Biorefineries). As for other countries and constituencies which come to mind and have reported on cellulose nanomaterial research, there’s Brazil, the European Union, Sweden, Finland, and Israel. I do not have details about government investments in those constituencies. I believe the report’s source supporting this contention is in Appendix E,  (from p. 41 of the PDF report),

Moon, Robert, and Colleen Walker. 2012. “Research into Cellulose
Nanomaterials Spans the Globe.” Paper360 7(3): 32–34. EBSCOhost. Accessed June 17, 2014 [behind a paywall]

Here’s a description of the barriers to commercialization (from p. 6 of the PDF report),

Clarifying the problems to be solved is a precursor to identifying solutions. The workshop identified critical barriers that are slowing commercialization. These barriers included lack of collaboration among potential producers and users; coordination of efforts among government, industry, and academia; lack of characterization and standards for cellulose nanomaterials; the need for greater market pull; and the need to overcome processing technical challenges related to cellulose nanomaterials dewatering and dispersion. While significant, these barriers are not insurmountable as long as the underlying technical challenges are properly addressed. With the right focus and sufficient resources, R&D should be able to overcome these key identified barriers.

There’s a list of potential applications (p. 7 of the PDF report).

Cellulose nanomaterials have demonstrated potential applications in a wide array of industrial sectors, including electronics, construction, packaging, food, energy, health care, automotive, and defense. Cellulose nanomaterials are projected to be less expensive than many other nanomaterials and, among other characteristics, tout an impressive strength-to-weight ratio (Erickson 2012, 26). The theoretical strength-to-weight performance offered by cellulose nanomaterials are unmatched by current technology (NIST 2008,
17). Furthermore, cellulose nanomaterials have proven to have major environmental benefits because they are recyclable, biodegradable, and produced from renewable resources.

I wonder if that strength-to-weight ratio comment is an indirect reference to carbon nanotubes which are usually the ‘strength darlings’ of the nanotech community.

More detail about potential applications is given on p. 9 of the PDF report,

All forms of cellulose nanomaterials are lightweight, strong, and stiff. CNCs possess photonic and piezoelectric properties, while CNFs can provide very stable hydrogels and aerogels. In addition, cellulose nanomaterials have low materials cost potential compared to other competing materials and, in their unmodified state, have so far shown few environmental, health, and safety (EHS) concerns (Ireland, Jones, Moon, Wegner, and Nieh 2014, 6). Currently, cellulose nanomaterials have demonstrated great potential for use in many areas, including aerogels, oil drilling additives, paints, coatings, adhesives, cement, food additives, lightweight packaging materials, paper, health care products, tissue scaffolding, lightweight vehicle armor, space technology, and automotive parts. Hence, cellulose nanomaterials have the potential to positively impact numerous industries. An important attribute of cellulose nanomaterials is that they are derived from renewable and broadly available resources (i.e., plant, animal, bacterial, and algal biomass). They are biodegradable and bring recyclability to products that contain them.

This particular passage should sound a familiar note for Canadians, from p. 11 of the PDF report,

However, commercialization of cellulose nanomaterials in the United States has been moving slowly. Since 2009, the USDA Forest Service has invested around $20 million in cellulose nanomaterials R&D, a small fraction of the $680 million spent on cellulose nanomaterials R&D by governments worldwide (Erickson 2014, 26). In order to remain globally competitive, accelerated research, development, and commercialization
of cellulose nanomaterials in the United States is imperative. Otherwise, the manufacturing of cellulose nanomaterials and cellulose nanomaterial-enabled products will be established by foreign producers, and the United States will be purchasing these materials from other countries. [emphasis mine] Establishing a large-scale production of cellulose nanomaterials in the United States is critical for creating new uses from wood—which is, in turn, vital to the future of forest management and the livelihood of landowners.

Here are some of the challenges and barriers identified in the workshop (pp. 19 – 21 of the PDF report),

Need for Characterization and Standards:
In order for a new material to be adopted for use, it must be well understood and end users must have confidence that the material is the same from one batch to the next. There is a need to better characterize cellulose nanomaterials with respect to their structure, surface properties, and performance. …

Production and Processing Methods:
Commercialization is inhibited by the lack of processing and production methods and know-how for ensuring uniform, reliable, and cost-effective production of cellulose nanomaterials, especially at large volumes. This is both a scale-up and a process control issue. …

Need for More Complete EHS Information:
Limited EHS information creates a significant barrier to commercialization because any uncertainty regarding material safety and the pending regulatory environment presents risk for early movers across all industries. …

Need for Market Pull and Cost/Benefit Performance:
As noted earlier, cellulose nanomaterials have potential applications in a wide range of areas, but there is no single need that is driving their commercial development. Stakeholders suggested several reasons, including lack of awareness of the material and its properties and a need for better market understanding. Commercialization will require market pull in order to incentivize manufacturers, yet there is no perceptible demand for cellulose nanomaterials at the moment. …

Challenge of Dewatering/Drying:
One of the most significant technical challenges identified is the dewatering of cellulose nanomaterials into a dry and usable form for incorporation into other materials. The lack of an energy-efficient, cost-effective drying process inhibits commercialization of cellulose nanomaterials, particularly for non-aqueous applications. Cellulose nanomaterials in low-concentration aqueous suspensions raise resource and transportation costs, which make them less viable commercially.

Technology Readiness:
Technology readiness is a major challenge in the adoption of cellulose nanomaterials. One obstacle in developing a market for cellulose nanomaterials is the lack of information on the basic properties of different types of cellulose nanomaterials, as noted in the characterization and standards discussion. …

The rest of the report concerns Research & Development (R&D) Roles and Priorities and the Path Forward. In total, this document is 44 pp. long and includes a number of appendices. Here’s where you can read “Cellulose Nanomaterials – A Path towards Commercialization.”

Final words on TAPPI’s June 2014 Nanotechnology for Renewable Materials conference

A July 8, 2014 news item on Nanowerk provides some statistics about the recently ended (June 23 – 26, 2014) TAPPI (Technical Association for the Pulp, Paper, Packaging and Converting Industries) Conference on Nanotechnology for Renewable Materials,

Over 230 delegates from 25 countries gathered in Vancouver, British Columbia, Canada last week at TAPPI’s 9th International Conference on Nanotechnology for Renewable Nanomaterials. “This year’s conference was exceptional,” noted co-chair Wadood Hamad, Priniciple Scientist, FPInnovations. “The keynote and technical presentations were of very high quality. The advancements made in many applications show great promise, and we will see expanded commercial use of these renewable biomaterials.”

An identical news item dated July 7, 2014 on Nanotechnology Now,notes the commercial announcements made during the conference,

Several key commercial announcements were made at this year’s conference, highlighting the tangible growth in this emerging market area of renewable biopolymers:

Celluforce, which opened their commercial plant in January 2012, shared six advanced commercial projects.

Imerys announced the launch of their new FiberLean™ MFC innovative composite, which enables a 10-15% reduction in fiber usage for papermaking applications.

Representatives from the newly formed BioFilaments shared information on their unique high performance biomaterial derived from wood cellulose to be used as reinforcing agents and rheological modifiers.

Blue Goose Biorefineries presented their patent-pending process for producing cellulose nanocrystals from wood pulp.

Nippon Paper Industries introduced Cellenpia, their cellulose nanofibers produced from their pre-commercial plant.

GL&V presented their commercial system, developed with the University of Maine, to produce cellulose nanofibrils at a very low energy cost.

American Process Inc. presented their latest results of producing lignin-coated nanocellulose particles using their AVAP® technology which produces a material that is more easily dispersed and has enhanced properties.

I wish them good luck with their projects.

Nanocellulose and an intensity of structural colour

I love the topic of structural colour (or color, depending on your spelling preferences) and have covered it many times and in many ways. One of the best pieces I’ve encountered about structural colour (an article by Christina Luiggi for The Scientist provided an overview of structural colour as it’s found in plants and animals) was featured in my Feb. 7, 2013 posting. If you go to my posting, you’ll find a link to Luiggi’s article which I recommend reading in its entirety if you have the time.

As for this latest nanocellulose story, a June 13, 2014 news item on Nanowerk describes University of Cambridge (UK) research into films and structural colour,

Brightly-coloured, iridescent films, made from the same wood pulp that is used to make paper, could potentially substitute traditional toxic pigments in the textile and security industries. The films use the same principle as can be seen in some of the most vivid colours in nature, resulting in colours which do not fade, even after a century.

Some of the brightest and most colourful materials in nature – such as peacock feathers, butterfly wings and opals – get their colour not from pigments, but from their internal structure alone.

Researchers from the University of Cambridge have recreated a similar structure in the lab, resulting in brightly-coloured films which could be used for textile or security applications.

A June 13, 2014 University of Cambridge news release, which originated the news item, describe the phenomenon of structural colour as it applies to cellulose materials,

In plants such as Pollia condensata, striking iridescent and metallic colours are the result of cellulose fibres arranged in spiral stacks, which reflect light at specific wavelengths. [emphasis mine]

Cellulose is made up of long chains of sugar molecules, and is the most abundant biomass material in nature. It can be found in the cells of every plant and is the main compound that gives cell walls their strength.

The news release goes on to provide a brief description of the research,

The researchers used wood pulp, the same material that is used for producing paper, as their starting material. Through manipulating the structure of the cellulose contained in the wood pulp, the researchers were able to fabricate iridescent colour films without using pigments.

To make the films, the researchers extracted cellulose nanocrystals from the wood pulp. When suspended in water, the rod-like nanocrystals spontaneously assemble into nanostructured layers that selectively reflect light of a specific colour. The colour reflected depends on the dimensions of the layers. By varying humidity conditions during the film fabrication, the researchers were able to change the reflected colour and capture the different phases of the colour formation.

Cellulose nanocrystals (CNC) are also known as nanocrystalline cellulose (NCC).

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

Controlled, Bio-inspired Self-Assembly of Cellulose-Based Chiral Reflectors by Ahu Gumrah Dumanli, Gen Kamita, Jasper Landman, Hanne van der Kooij, Beverley J. Glover, Jeremy J. Baumberg, Ullrich Steiner, and Silvia Vignolini. Optical Materials Article first published online: 30 MAY 2014 DOI: 10.1002/adom.201400112

© 2014 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

While the researchers have supplied an image of the Pollia condensata, I prefer this one, which is also featured in my Feb. 7, 2013 posting,

AGELESS BRILLIANCE: Although the pigment-derived leaf color of this decades-old specimen of the African perennial Pollia condensata has faded, the fruit still maintains its intense metallic-blue iridescence.COURTESY OF P.J. RUDALL [downloaded from http://www.the-scientist.com/?articles.view/articleNo/34200/title/Color-from-Structure/]

AGELESS BRILLIANCE: Although the pigment-derived leaf color of this decades-old specimen of the African perennial Pollia condensata has faded, the fruit still maintains its intense metallic-blue iridescence.COURTESY OF P.J. RUDALL [downloaded from http://www.the-scientist.com/?articles.view/articleNo/34200/title/Color-from-Structure/]

Stunning, non?

Hydrodynamic alignment and assembly of nano-fibrils results in cellulose fibers stronger than both aluminum and steel

A June 2, 2014 news item on Azonano describes the new fibres (which come from wood),

“Our filaments are stronger than both aluminium and steel per weight,” emphasizes lead author Prof. Fredrik Lundell from the Wallenberg Wood Science Center at the Royal Swedish Institute of Technology KTH in Stockholm. “The real challenge, however, is to make bio based materials with extreme stiffness that can be used in wind turbine blades, for example. With further improvements, in particular increased fibril alignment, this will be possible.”

The June 2, 2014 DESY ( one of the world’s leading accelerator centres) press release describes the research in detail,

A Swedish-German research team has successfully tested a new method for the production of ultra-strong cellulose fibres at DESY’s research light source PETRA III. The novel procedure spins extremely tough filaments from tiny cellulose fibrils by aligning them all in parallel during the production process. …

For their method, the researchers took tiny, nanometre-sized cellulose fibrils and fed them together with water through a small channel. Two additional water jets coming in perpendicular from left and right accelerate the fibril flow. “Following the acceleration, all nano fibrils align themselves more or less parallel with the flow,” explains co-author Dr. Stephan Roth from DESY, head of the experimental station P03 at PETRA III where the experiments took place. “Furthermore, salt is added to the outer streams. The salt makes the fibrils attach to each other, thereby locking the structure of the future filament.”

Finally, the wet filaments are left to dry in air where they shrink to form a strong fibre. “Drying takes a few minutes in air,” explains co-author Dr. Daniel Söderberg from KTH. “The resulting material is completely compatible with the biosphere, since the natural structure of the cellulose is maintained in the fibrils. Thus, it is biodegradable and compatible with human tissue.”

The bright X-ray light from PETRA III enabled the scientists to follow the process and check the configuration of the nano fibrils at various stages in the flow. “Research today is driven by cross-disciplanary collaborations,” underlines Söderberg. “Without the excellent competence and possibilities brought into the project by the team of DESY’s experimental station P03 this would not have been possible.”

As the scientists write, their fibres are much stronger than all other previously reported artificial filaments from cellulose nano fibrils. In fact, the artificial filaments can rival the strongest natural cellulose pulp fibres extracted from wood at the same degree of alignment of the nano fibrils. “In principle, we can make very long fibres,” says Lundell. “Up until now we have made samples that where ten centimetres long or so, but that is more of an equipment issue than a fundamental problem.”

For their experiments, the researchers have used nano fibrils extracted from fresh wood. “In principle, it should be possible to obtain fibrils from recycled paper also,” says Lundell. But he cautions: “The potential of recycled material in this context needs further investigations.”

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

Hydrodynamic alignment and assembly of nano-fibrils resulting in strong cellulose filaments by Karl M. O. Håkansson, Andreas B. Fall, Fredrik Lundell, Shun Yu, Christina Krywka, Stephan V. Roth, Gonzalo Santoro, Mathias Kvick, Lisa Prahl Wittberg, Lars Wågberg & L. Daniel Söderberg. Nature Communications, 2014; DOI: 10.1038/ncomms5018

This is an open access paper.

I posted a June 3, 2014 item on cellulose nanofibriil titled:  Doubling paper strength with nanofibrils; a nanocellulose.

Richard Berry (CelluForce) wins TAPPI’s first technical award in the nanotechnology division

Another day, another award for Dr. Richard Berry, as per this May 22, 2014 news item on Nanowerk (Note: A link has been removed),

Dr. Richard Berry of CelluForce has been named the first recipient of TAPPI’s International Nanotechnology Division’s Technical Award. This award recognizes outstanding accomplishments or contributions which have advanced the responsible and sustainable production and use of renewable nanomaterials. Dr. Berry will be presented with this award at TAPPI’s 2014 International Conference on Nanotechnology for Renewable Materials to be held June 23-26, 2014 in Vancouver, British Columbia.

Currently Vice-President and Chief Technology Officer for CelluForce, Berry has had a storied career (from the news item),

Prior to moving to CelluForce in 2011 he was Principal Scientist and leader of the nanotechnology initiative at FPInnovations. … He’s received many awards including the Nano-industry award from Nano Québec for his exceptional contribution to the development of cellulose nanocrystals, the Purvis Memorial Award and he’s been named one of Canada’s Clean 50 honourees. The initiatives Dr. Berry has spearheaded in recent years have allowed Canada to position itself as a world leader in the development of the new nanotechnology industry. This work was recognised through the 2012 NSERC Synergy award for innovation given to McGill University, FPInnovations, ArboraNano, and CelluForce .. .

I notice that the news item uses the term cellulose nanocrystals (CNC) rather than nanocrystalline cellulose (NCC). Perhaps this means someone will put me out of my misery soon and declare one term or other the winner.

As for the reference to Canada as a “a world leader in the development of the new nanotechnology industry,” that seems a little grandiose and odd. To my knowledge, no one refers to a ‘nanotechnology industry’. I believe the writer is trying say that Canada is a leader in the production of CNC. I wonder if they’ve (CelluForce) dealt with their stockpile first mentioned here in an Oct. 3, 2013 posting and again in an April 10, 2014 posting about the US Dept. of Agriculture’s workshop on commercializing cellulose nanomaterials. Should anyone know of the stockpile’s status at this time, please do let me know.

Here’s a link to the 2014 TAPPI Nanotechnology conference website here. and an interview here (Aug. 27, 2010)  where Dr. Berry very kindly answered my questions about what was then called, indisputably, nanocrystalline cellulose.

Mopping up that oil spill with a nanocellulose sponge and a segue into Canadian oil and politics

Empa (Swiss Federal Laboratories for Materials Science and Technology or ,in German, Eidgenössische Materialprüfungs- und Forschungsanstalt) has announced the development of a nanocellulose sponge useful for cleaning up oil spills in a May 5, 2014 news item on Nanowerk (Note: A link has been removed),

A new, absorbable material from Empa wood research could be of assistance in future oil spill accidents: a chemically modified nanocellulose sponge. The light material absorbs the oil spill, remains floating on the surface and can then be recovered. The absorbent can be produced in an environmentally-friendly manner from recycled paper, wood or agricultural by-products (“Ultralightweight and Flexible Silylated Nanocellulose Sponges for the Selective Removal of Oil from Water”).

A May 2, 2014 Empa news release (also on EurekAlert*}, which originated the news item, includes a description of the potential for oil spills due to transport issues, Empa’s proposed clean-up technology, and a request for investment,

All industrial nations need large volumes of oil which is normally delivered by ocean-going tankers or via inland waterways to its destination. The most environmentally-friendly way of cleaning up nature after an oil spill accident is to absorb and recover the floating film of oil. The Empa researchers Tanja Zimmermann and Philippe Tingaut, in collaboration with Gilles Sèbe from the University of Bordeaux, have now succeeded in developing a highly absorbent material which separates the oil film from the water and can then be easily recovered, “silylated” nanocellulose sponge. In laboratory tests the sponges absorbed up to 50 times their own weight of mineral oil or engine oil. They kept their shape to such an extent that they could be removed with pincers from the water. The next step is to fine tune the sponges so that they can be used not only on a laboratory scale but also in real disasters. To this end, a partner from industry is currently seeked.

Here’s what the nanocellulose sponge looks like (oil was dyed red and the sponge has absorbed it from the water),

The sponge remains afloat and can be pulled out easily. The oil phase is selectively removed from the surface of water. Image: Empa

The sponge remains afloat and can be pulled out easily. The oil phase is selectively removed from the surface of water.
Image: Empa

The news release describes the substance, nanofibrillated cellulose (NFC), and its advantages,

Nanofibrillated Cellulose (NFC), the basic material for the sponges, is extracted from cellulose-containing materials like wood pulp, agricultural by products (such as straw) or waste materials (such as recycled paper) by adding water to them and pressing the aqueous pulp through several narrow nozzles at high pressure. This produces a suspension with gel-like properties containing long and interconnected cellulose nanofibres .

When the water from the gel is replaced with air by freeze-drying, a nanocellulose sponge is formed which absorbs both water and oil. This pristine material sinks in water and is thus not useful for the envisaged purpose. The Empa researchers have succeeded in modifying the chemical properties of the nanocellulose in just one process step by admixing a reactive alkoxysilane molecule in the gel before freeze-drying. The nanocellulose sponge loses its hydrophilic properties, is no longer suffused with water and only binds with oily substances.

In the laboratory the “silylated” nanocellulose sponge absorbed test substances like engine oil, silicone oil, ethanol, acetone or chloroform within seconds. Nanofibrillated cellulose sponge, therefore, reconciles several desirable properties: it is absorbent, floats reliably on water even when fully saturated and is biodegradable.

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

Ultralightweight and Flexible Silylated Nanocellulose Sponges for the Selective Removal of Oil from Water by Zheng Zhang, Gilles Sèbe, Daniel Rentsch, Tanja Zimmermann, and Philippe Tingaut. Chem. Mater., 2014, 26 (8), pp 2659–2668 DOI: 10.1021/cm5004164 Publication Date (Web): April 10, 2014

Copyright © 2014 American Chemical Society

This article is behind a paywall.

I featured ‘nanocellulose and oil spills’ research at the University Wisconsin-Madison in a Feb. 26, 2014 post titled, Cleaning up oil* spills with cellulose nanofibril aerogels (Note: I corrected a typo in my headline hence the asterisk). I also have a Dec. 31, 2013 piece about a nanotechnology-enabled oil spill recovery technology project (Naimor) searching for funds via crowdfunding. Some major oil projects being considered in Canada and the lack of research on remediation are also mentioned in the post.

Segue Alert! As for the latest on Canada and its oil export situation, there’s a rather interesting May 2, 2014 Bloomberg.com article Canada Finds China Option No Easy Answer to Keystone Snub‘ by Edward Greenspon, Andrew Mayeda, Jeremy van Loon and Rebecca Penty describing two Canadian oil projects and offering a US perspective,

It was February 2012, three months since President Barack Obama had phoned the Canadian prime minister to say the Keystone XL pipeline designed to carry vast volumes of Canadian crude to American markets would be delayed.

Now Harper [Canadian Prime Minister Stephen Harper] found himself thousands of miles from Canada on the banks of the Pearl River promoting Plan B: a pipeline from Alberta’s landlocked oil sands to the Pacific Coast where it could be shipped in tankers to a place that would certainly have it — China. It was a country to which he had never warmed yet that served his current purposes. [China’s President at that time was Hu Jintao, 2002 – 2012; currently the President is Xi Jinping, 2013 – ]

The writers do a good job of describing a number of factors having an impact on one or both of the pipeline projects. However, no mention is made in the article that Harper is from the province of Alberta and represents that province’s Calgary Southwest riding. For those unfamiliar with Calgary, it is a city dominated by oil companies. I imagine Mr. Harper is under considerable pressure to resolve oil export and transport issues and I would expect they would prefer to resolve the US issues since many of those oil companies in Calgary have US headquarters.

Still, it seems simple, if the US is not interested as per the problems with the Keystone XL pipeline project, ship the oil to China via a pipeline through the province of British Columbia and onto a tanker. What the writers do not mention is yet another complicating factor, Trudeau, both Justin and, the deceased, Pierre.

As Prime Minister of Canada, Pierre Trudeau was unloved in Alberta, Harper’s home province, due to his energy policies and the formation of the National Energy Board. Harper appears, despite his denials, to have an antipathy towards Pierre Trudeau that goes beyond the political to the personal and it seems to extend beyond Pierre’s grave to his son, Justin. A March 21, 2014 article by Mark Kennedy for the National Post describes Harper’s response to Trudeau’s 2000 funeral this way,

Stephen Harper, then the 41-year-old president of the National Citizens Coalition (NCC), was a proud conservative who had spent three years as a Reform MP. He had entered politics in the mid-1980s, in part because of his disdain for how Pierre Trudeau’s “Just Society” had changed Canada.

So while others were celebrating Trudeau’s legacy, Harper hammered out a newspaper article eviscerating the former prime minister on everything from policy to personality.

Harper blasted Trudeau Sr. for creating “huge deficits, a mammoth national debt, high taxes, bloated bureaucracy, rising unemployment, record inflation, curtailed trade and declining competitiveness.”

On national unity, he wrote that Trudeau was a failure. “Only a bastardized version of his unity vision remains and his other policies have been rejected and repealed by even his own Liberal party.”

Trudeau had merely “embraced the fashionable causes of his time,” wrote Harper.

Getting personal, he took a jab at Trudeau over not joining the military during the Second World War: “He was also a member of the ‘greatest generation,’ the one that defeated the Nazis in war and resolutely stood down the Soviets in the decades that followed. In those battles however, the ones that truly defined his century, Mr. Trudeau took a pass.”

The article was published in the National Post Oct. 5, 2000 — two days after the funeral.

Kennedy’s article was occasioned by the campaign being led by Harper';s Conservative party against the  leader (as of April 2013) of the Liberal Party, Justin Trudeau.

It’s hard to believe that Harper’s hesitation over China is solely due to human rights issues especially  since Harper has not been noted for consistent interest in those issues and, more particularly, since Prime Minister Pierre Trudeau was one of the first ‘Western’ leaders to visit communist China . Interestingly, Harper has been much more enthusiastic about the US than Pierre Trudeau who while addressing the Press Club in Washington, DC in March 1969, made this observation (from the Pierre Trudeau Wikiquote entry),

Living next to you [the US] is in some ways like sleeping with an elephant. No matter how friendly and even-tempered is the beast, if I can call it that, one is affected by every twitch and grunt.

On that note, I think Canada is always going to be sleeping with an elephant; the only question is, who’s the elephant now? In any event, perhaps Harper is more comfortable with the elephant he knows and that may explain why China’s offer to negotiate a free trade agreement has been left unanswered (this too was not noted in the Bloomberg article). The offer and lack of response were mentioned by Yuen Pau Woo, President and CEO of the Asia Pacific Foundation of Canada, who spoke at length about China, Canada, and their trade relations at a Jan. 31, 2014 MP breakfast (scroll down for video highlights of the Jan. 31, 2014 breakfast) held by Member of Parliament (MP) for Vancouver-Quadra, Joyce Murray.

Geopolitical tensions and Canadian sensitivities aside, I think Canadians in British Columbia (BC), at least, had best prepare for more oil being transported and the likelihood of spills. In fact, there are already more shipments according to a May 6, 2014 article by Larry Pynn for the Vancouver Sun,

B.C. municipalities work to prevent a disastrous accident as rail transport of oil skyrockets

The number of rail cars transporting crude oil and petroleum products through B.C. jumped almost 200 per cent last year, reinforcing the resolve of municipalities to prevent a disastrous accident similar to the derailment in Lac-Mégantic in Quebec last July [2013].

Transport Canada figures provided at The Vancouver Sun’s request show just under 3,400 oil and petroleum rail-car shipments in B.C. last year, compared with about 1,200 in 2012 and 50 in 2011.

The figures come a week after The Sun revealed that train derailments jumped 20 per cent to 110 incidents last year in B.C., the highest level in five years.

Between 2011 and 2012, there was an increase of 2400% (from 50 to 1200) of oil and petroleum rail-car shipments in BC. The almost 300% increase in shipments between 2012 and 2013 seems paltry in comparison.  Given the increase in shipments and the rise in the percentage of derailments, one assumes there’s an oil spill waiting to happen. Especially so, if the Canadian government manages to come to an agreement regarding the proposed pipeline for BC and frankly, I have concerns about the other pipeline too, since either will require more rail cars, trucks, and/or tankers for transport to major centres edging us all closer to a major oil spill.

All of this brings me back to Empa, its oil-absorbing nanocellulose sponges, and the researchers’ plea for investors and funds to further their research. I hope they and all the other researchers (e.g., Naimor) searching for ways to develop and bring their clean-up ideas to market find some support.

*EurekAlert link added May 7, 2014.

ETA May 8, 2014:  Some types of crude oil are more flammable than others according to a May 7, 2014 article by Lindsay Abrams for Salon.com (Note: Links have been removed),

Why oil-by-rail is an explosive disaster waiting to happen
A recent spate of fiery train accidents all have one thing in common: highly volatile cargo from North Dakota

In case the near continuous reports of fiery, deadly oil train accidents hasn’t been enough to convince you, Earth Island Journal is out with a startling investigative piece on North Dakota’s oil boom and the dire need for regulations governing that oil’s transport by rail.

The article is pegged to the train that derailed and exploded last summer in  [Lac-Mégantic] Quebec, killing 47 people, although it just as well could have been the story of the train that derailed and exploded in Alabama last November, the train that derailed and exploded in North Dakota last December, the train that derailed and exploded in Virginia last week or — let’s face it — any future accidents that many see as an inevitability.

The Bakken oil fields in North Dakota are producing over a million barrels of crude oil a day, more than 60 percent of which is shipped by rail. All that greenhouse gas-emitting fossil fuel is bad enough; that more oil spilled in rail accidents last year than the past 35 years combined is also no small thing. But the particular chemical composition of Bakken oil lends an extra weight to these concerns: according to the Pipeline and Hazardous Materials Safety Administration, it may be more flammable and explosive than traditional crude.

While Abrams’ piece is not focused on oil cleanups, it does raise some interesting questions about crude oil transport and whether or not the oil from Alberta might also be more than usually dangerous.

TAPPI 2014 keynote speakers: Al Ward and Per Swending

I’m pretty sure I saw the keynote speakers listed on the 2014 TAPPI International Conference on Nanotechnology of Renewable Materials website the last time I checked it. (The conference is being held in Vancouver, Canada from June 23-26. ) Likely, the conference organizers have decided to publicize their keynote speakers, Al Ward and Per Swending, to *generate interest (from the April 23, 2014 news item on the Pulp & Paper Canada website),

Al Ward of Alberta-Pacific Forest Industries and Imerys FiberLean’s Per Swending will be keynote presenters at the TAPPI nanotechnology conference in Vancouver.

The TAPPI International Conference on Nanotechnology for Renewable Materials, held on June 23 – 26, 2014, explores how nanotechnology can transform biomaterials into high-value products.

“The science of nanotechnology in renewable materials continues to advance rapidly and our keynote speakers will provide an exciting update on the most recent developments in commercialization and research for improving cellulose based products,” notes Orlando Rojas of North Carolina State University, co-chair of the conference.

Here’s more about Ward and Swending from the conference’s keynotes page,

The Nano Puzzle–Putting the Pieces Together
8:00, Tuesday, 25 June

Al Ward is President and COO of Alberta-Pacific Forest Industries Inc. (Al-Pac), the newest, largest single line kraft pulp mill in North America, with production starting in 1993. Mr. Ward has a Masters Degree in Business Administration from the University of Alberta and over 30 years of experience in the forest industry in a various production, technical and senior management positions. The company utilizes some of the latest in chemical pulping technology and annually produces approximately 650,000 tonnes of northern bleached hardwood and softwood kraft pulp.  Al-Pac is known as an environmental leader, practices sustainable forest management and was third party FSC certified in 2005 and SFI dual certified in 2013. The company employs 450 full time employees and approximately 1,000 contractors and has been voted one of Canada’s “Top 100 Employers for 2014” and one of “Alberta’s Top 60 Employers for 2013” for seven years running.

Mr. Ward is the past Chairman and a current board member of FPInnovations, Canada’s  Forest and Pulp and Paper Research Institute and currently holds a board position on the Forest Products Association of Canada (FPAC).  Over his many years in the Industry, he has served on a number of industry related technical committees with Pulp and Paper Technical Association of Canada (PAPTAC) and Technical Association of the Pulp and Paper Industry (TAPPI).  Al also was involved with the Alberta Economic Development Authority which is a business advisory board to the Premier and Cabinet of Alberta with up to 65 CEO’s and business leaders who are appointed by Ministerial Order to provide sound business advice to the Premier and Cabinet. He is currently chair of the Alberta provincial steering committee for forest sector related nano-technology research as well as a board member of Arboranano the Canadian Forest NanoProducts Network, an R&D network where nanotechnology and forest-sector expertise are committed to creating a new Canadian bio-economy founded on innovative, highly-engineered, nanotechnology-based, carbon-neutral products created from Canada’s vast forest resource.  Mr. Ward is also heavily involved in the transformation efforts of the forest sector in Canada to new bio products, fuels and chemicals.

Commercial Break-Through in MFC Processing
8:00, Wednesday, 26 June

Per [Per Swending, Commercial Director Imerys FiberLeanTM] has worked 35 years for the paper industry. After chemical engineering studies in Gothenburg Sweden he joined Eka Chemicals (today AkzoNobel) in 1979 and was part of the team that developed the first nano-particle based retention aid system, Compozil. His work at Eka Chemicals gradually progressed from R&D to wet end application and into commercial roles via a period in product management. In 1989 he joined Stora Papyrus Mölndal for a role as technical manager, coated papers. The combination of wet end and coating experience facilitated a move to English China Clays in 1994. The career in what has now become Imerys started as sales director for Scandinavia and has moved through various key account manager roles to product management and global marketing to the current role in the FiberLeanTM team. Per was one of the inventors of the FiberLeanTM process and is now heading up the commercialisation effort for this breakthrough technology. Off-duty, his favourite activities are motorcycling, skiing, kayaking and cooking.

Imerys is announcing a commercial break-through in MFC processing with over 3000 dry metric tons of MFC capacity installed in Europe and North America with one commercial and one pilot plant running.  Branded as FiberLeanTM, Imerys´ MFC offers paper makers the opportunity to become more cost competitive and to develop new differentiated products. Imerys plans to be the world leading MFC producer and is currently in discussions aimed at building several customer plants around the world.

As best I can determine, I last mentioned the 2014 TAPPI conference in Vancouver in a November 14, 2013 posting.

* April 25, 2014 at 3:33 pm PDT, Removed the word ‘get’ from the sentence as it was redundant.

Inhibiting viruses with nanocrystalline cellulose (NCC) in Finland

Research and interest in cellulose nanomaterials of one kind or another seems to be reaching new heights. That’s my experience since this is my third posting on the topic in one week.

The latest research features NCC (nanocrystalline cellulose [NCC] or, as it’s sometimes known, cellulose nanocrystals [CNC]) ,as a ‘viral inhibitor’ and is described in an April 15, 2014 news item on Nanowerk,

Researchers from Aalto University [Finland] and and the University of Eastern Finland have succeeded in creating a surface on nano-sized cellulose crystals that imitates a biological structure. The surface adsorbs viruses and disables them. The results can prove useful in the development of antiviral ointments and surfaces, for instance.

There are many viral diseases in the world for which no pharmaceutical treatment exists. These include, among others, dengue fever, which is spread by mosquitoes in the tropics, as well as a type of diarrhea, which is more familiar in Finland and is easily spread by the hands and can be dangerous especially for small children and the elderly.

An April 15, 2014 Aalto University news release, which originated the news item, provides more detail,

Researchers at Aalto University and the University of Eastern Finland have now succeeded in preliminary tests to prevent the spread of one type of virus into cells with the help of a new type of nanocrystalline cellulose. Nano-sized cellulose crystals were manufactured out of cotton fibre or filter paper with the help of sulphuric acid, causing sulphate ions with negative charges to attach to their surfaces. The ions then attached to alphaviruses used in the test and neutralised them. When the researchers replaced the sulphate ions with cellulose derivatives that imitate tyrosine sulphates, the activity of the viruses was further reduced. The experiments succeeded in preventing viral infection in 88-100 percent of the time with no noticeable effect on the viability of the cells by the nanoparticles. The research findings were published in the journal Biomacromolecules.

Here’s a diagram illustrating how the new type of NCC works,

Courtesy of Aalto University

Courtesy of Aalto University

The news release includes perspectives from the researchers,

’Certain cellulose derivatives had been seen to have an impact on viruses before. The nano scale increases the proportion of the surface area to that of the number of grams to a very high level, which is an advantage, because viruses specifically attach themselves to surfaces. Making the cellulose crystals biomimetic, which means that they mimic biological structures, was an important step, as we know that in nature viruses often interact specifically with tyrosine structures,’ he [Jukka Seppälä, Professor of Polymer Technology at Aalto University] says.

Both Jukka Seppälä and Ari Hinkkanen, Professor of Gene Transfer Technology at the University of Eastern Finland, emphasise that the research is still in the early stages.

‘Now we know that the attachment of a certain alphavirus can be effectively prevented when we use large amounts of nanocrystalline cellulose.  Next we need to experiment with other alpha viruses and learn to better understand the mechanisms that prevent viral infection. In addition, it is necessary to ascertain if cellulose can also block other viruses and in what conditions, and to investigate whether or not the sulphates have a deleterious effects on an organism,’ Ari Hinkkanen explains.

According to Kristiina Järvinen, Professor of Pharmaceutical Technology at the University of Eastern Finland, there are many routes that can be taken in the commercialisation of the results. The development of an antiviral medicine is the most distant of these; the idea could be sooner applied in disinfectant ointments and coatings, for instance.

‘It would be possible to provide protection against viruses, spread by mosquitoes, by applying ointment containing nanocrystalline cellulose onto the skin. Nanocrystalline cellulose applied on hospital door handles could kill viruses and prevent them from spreading.  However, we first need to ascertain if the compounds will remain effective in a non-liquid form and how they work in animal tests,’ she ponders.

For the curious, here’s a link to and a citation for the paper,

Synthesis of Cellulose Nanocrystals Carrying Tyrosine Sulfate Mimetic Ligands and Inhibition of Alphavirus Infection by Justin O. Zoppe, Ville Ruottinen, Janne Ruotsalainen, Seppo Rönkkö, Leena-Sisko Johansson, Ari Hinkkanen, Kristiina Järvinen, and Jukka Seppälä. Biomacromolecules, 2014, 15 (4), pp 1534–1542 DOI: 10.1021/bm500229d Publication Date (Web): March 14, 2014

Copyright © 2014 American Chemical Society

This paper is behind a paywall.

As for my other recent postings on cellulose nanomaterials, there’s this April 14, 2014 piece titled: Preparing nanocellulose for eventual use in dressings for wounds and this from April 10, 2014 titled: US Dept. of Agriculture wants to commercialize cellulose nanomaterials.

Preparing nanocellulose for eventual use in* dressings for wounds

Michael Berger writes about a medical application for wood-based nanocellulose in an April 10, 2014 Nanowerk Spotlight article by featuring some recent research from Norway (Note: Links have been removed),

Cellulose is a biopolymer consisting of long chains of glucose with unique structural properties whose supply is practically inexhaustible. It is found in the cell walls of plants where it serves to provide a supporting framework – a sort of skeleton. Nanocellulose from wood – i.e. wood fibers broken down to the nanoscale – is a promising nanomaterial with potential applications as a substrate for printing electronics, filtration, or biomedicine.

Researchers have now reported on a method to control the surface chemistry of nanocellulose. The paper appeared in the April 8, 2014 online edition of the Journal of Biomaterials Applications (“Pretreatment-dependent surface chemistry of wood nanocellulose for pH-sensitive hydrogels”).

Using a specific chemical pretreatment as example (carboxymethylation and periodate oxidation), a team from the Paper and Fibre Research Institute (PFI) in Norway demonstrated that they could manufacture nanofibrils with a considerable amount of carboxyl groups and aldehyde groups, which could be applied for functionalizing the material.

The Norwegian researchers are working within the auspices of PFI‘s NanoHeal project featured in my Aug. 23, 2012 posting. It’s good to see that progress is being made. From the Berger’s article,

A specific activity that the PFI researchers and collaborators are working with in the NanoHeal project is the production of an ultrapure nanocellulose which is important for biomedical applications. Considering that the nanocellulose hydrogel material can be cross-linked and have a reactive surface chemistry there are various potential applications.

“A concrete application that we are working with in this specific case is as dressing for wound healing, another is scaffolds,” adds senior research scientist and co-author Kristin Syverud.

“Production of an ultrapure nanocellulose quality is an activity that we are intensifying together with our research partners at the Institute of Cancer Research and Molecular Medicine in Trondheim,” notes Chinga-Carrasco [Gary Chinga-Carrasco, a senior research scientist at PFI]. “The results look good and we expect to have a concrete protocol for production of ultrapure nanocellulose soon, for an adequate assessment of its biocompatibility.”

“We have various groups working with assessment of the suitability of nanocellulose as a barrier against wound bacteria and also with the assessment of the cytotoxicity and biocompatibility,” he says. “However, as a first step we have intensified our work on the production of nanocellulose that we expect will be adequate for wound dressings, part of these activities are described in this paper.”

I suggest reading Berger’s article in its totality for a more detailed description of the many hurdles researchers still have to overcome. For the curious, here’s a link to and a citation for the paper,

Pretreatment-dependent surface chemistry of wood nanocellulose for pH-sensitive hydrogels by Gary Chinga-Carrasco & Kristin Syverud. Published online before print April 8, 2014, doi: 10.1177/0885328214531511 J Biomater Appl April 8, 2014 0885328214531511

This paper is behind a paywall.

I was hoping to find someone from this group in the list of speakers for 2014 TAPPI Nanotechnology conference website here (officially known as 2014 TAPPI [Technical Association of the Pulp and Paper Industry] International Conference on Nanotechnology for Renewable Materials) being held in Vancouver, Canada (June 23-26, 2014) but had no luck.

* ‘as’ changed to ‘in’ Apr.14.14 10:50 am PDT in headline