Tag Archives: Aalto University

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.

Cancer as a fashion statement at the University of British Columbia (Canada) and a Marimekko dress made of birch in Finland

The ‘Fashioning Cancer Project’ at the University of British Columbia (UBC) bears some resemblance to the types of outreach projects supported by the UK’s Wellcome Trust (for an example see my June 21, 2011 posting) where fashion designers are inspired by some aspect of science. Here’s more about the ‘Fashioning Cancer Project’ and its upcoming fashion show (on March 25, 2014). From the March 12, 2014 UBC news release (Note: Links have been removed),

A UBC costume design professor has created a collection of ball gowns inspired by microscopic photos of cancer cells and cellular systems to get people talking about the disease, beauty and body image.

The project aims to create alternative imagery for discussions of cancer, to complement existing examples such as the pink ribbon, which is an important symbol of cancer awareness, but may not accurately represent women’s experience with the disease.

“Many women who have battled cancer express a disconnect with the fashion imagery that commonly represents the disease,” says Jacqueline Firkins, an assistant professor in UBC’s Dept. of Theatre and Film, who designed the collection of 10 dresses and dubbed the work ‘Fashioning Cancer: The Correlation between Destruction and Beauty.’

Inspired by cellular images captured by researchers in the lab of UBC scientist Christian Naus, a Peter Wall Distinguished Scholar in Residence, the project seeks to create artistic imagery based on the disease itself.

“My hope is that somehow through fashion, I more closely tap into what a woman might be feeling about her body as she undergoes the disease, but simultaneously reflect a strength, beauty, and resilience,” says Firkins, who will use the collection to raise money for cancer research, patients and survivors.

“This will be an opportunity for people to share their thoughts about the gowns,” says Firkins. “Are they too pretty to reflect something as destructive as cancer? Do they encourage you to tell your own story? Do they evoke any emotions related to your own experience?”

Before giving you where and when, here are two images (a cell and a dress based on the cell),

http://news.ubc.ca/2014/03/12/prof-challenges-cancer-fashion/

Cell7_brain_cells_in_a_dish; Astrocytes from the brain growing in a culture dish. Green colour indicates the cytoskeleton of these cells, red colour shows specific membrance [sic] channels (gap junctions), blue colour indicates the cell nuclei (DNA). The ability to grow cells in a dish has contributed to our understand of the changes these cells undergo when they become channels. Photo credit: John Bechberger, MSc., Christian Naus, PhD.

Cell7_Mercedes_de_la_Zerda: Dress modeled by BFA Acting student Mercedes de la Zerda.Black organza cap sleeve w/ sheer top and multicolour organza diagonal trim. Photo credit: Tim Matheson

Cell7_Mercedes_de_la_Zerda: Dress modeled by BFA Acting student Mercedes de la Zerda.Black organza cap sleeve w/ sheer top and multicolour organza diagonal trim. Photo credit: Tim Matheson

Details about the show (from the UBC event description webpage where you can also find a slide show more pictures),

  • Event: Fashioning Cancer: The Correlation between Destruction and Beauty
  • Date: Tue. March 25, 2014 | Time: 12-1pm
  • Location: UBC’s Frederic Wood Theatre, 6354 Crescent Rd.
  • MAP: http://bit.ly/1fZ4bC8

On a more or less related note, Aalto University (Finland) has announced a dress made of birch cellulose fibre, from a March 13, 2014 news item on ScienceDaily,

The first garment made out of birch cellulose fibre using the Ioncell method is displayed at a fashion show in Finland on 13 March [2014]. The Ioncell method, which was developed by researchers at Aalto University, is an environmentally friendly alternative to cotton in textile production. The dress produced for Marimekko is a significant step forward in the development of fibre for industrial production.

Researchers were looking for new alternatives to cotton, because demand for textile fibres is expected to nearly double by 2030. The raw material for the Ioncell fibre is a birch-based pulp from Finnish pulp mills. Growing birch wood does not require artificial irrigation in its native habitat, for instance.

The Aalto University March 12, 2014 news release, which originated the news item, describes the new Ioncell fibre and its relationship with Finnish clothing company Marimekko,

The production method for Ioncell has been developed by Professor Herbert Sixta’s research group. The method is based on a liquid salt (ionic liquid) developed under the guidance of Professor Ilkka Kilpeläinen which is a very efficient cellulose solvent. The fibres derived from it are carded and spun to yarns at the Textile University of Börås in Sweden.

‒ We made a breakthrough in the development of the method about a year ago. Progress has been rapid since then. [see my Oct. 3, 2013 posting for another Finnish team’s work with wood cellulose to create fabric]  Production of the fibre and the thread is still a cumbersome process, but we have managed to triple the amount of fibre that is produced in six months. The quality has also improved: the fibers are stronger and of more even quality, Professor Sixta says with satisfaction.

The surface of the ready textile has a dim glow and it is pleasing to the touch. According to Sixta, because of its strength, the strength properties of the Ioncell fibre are equal or even better than other pulp-based fibres on the market. The fibres are even stronger than cotton and viscose.

The Finnish textile and clothing design company Marimekko became inspired by the new fibre at an event organised by the Finnish Bioeconomy Cluster FIBIC, which coordinates bioeconomy research, and immediately got in touch with Professor Herbert Sixta at Aalto University.

‒ We monitor product development for materials closely in order to be able to offer our customers new and more ecological alternatives. It was a wonderful opportunity to be able to join this Aalto University development project at such an early stage. Fibre made from birch pulp seems to be a promising material by virtue of its durability and other characteristics, and we hope that we will soon be able to utilise this new material in our collections, says Noora Niinikoski, Head of Fashion at Marimekko.

Here’s the birch cellulose dress,

Marimekko Birch Dress Courtesy: Aalto University

Let’s all have a fashionable day!

INFERNOS: realizing Maxwell’s Demon

Before getting to the INFERNOS project and its relationship to Maxwell’s demon, I want to share a pretty good example of this ‘demon’ thought experiment which, as recently as Feb. 4, 2013, I featured in a piece about quantum dots,

James Clerk Maxwell, physicist,  has entered the history books for any number reasons but my personal favourite is Maxwell’s demon, a thought experiment he proposed in the 1800s to violate the 2nd law of thermodynamics. Lisa Zyga in her Feb. 1, 2013 article for phys.org provides an explanation,

When you open your door on a cold winter day, the warm air from your home and the cold air from outside begin to mix and evolve toward thermal equilibrium, a state of complete entropy where the temperatures outside and inside are the same. This situation is a rough example of the second law of thermodynamics, which says that entropy in a closed system never decreases. If you could control the air flow in a way that uses a sufficiently small amount of energy, so that the entropy of the system actually decreases overall, you would have a hypothetical mechanism called Maxwell’s demon.

An Oct. 9, 2013 news item on Nanowerk ties together INFERNOS and the ‘demon’,

Maxwell’s Demon is an imaginary creature that the mathematician James Clerk Maxwell created in 1897. The creature could turn heat into work without causing any other change, which violates the second law of thermodynamics. The primary goal of the European project INFERNOS (Information, fluctuations, and energy control in small systems) is to realize experimentally Maxwell’s Demon; in other words, to develop the electronic and biomolecular nanodevices that support this principle.

The Universitat de Barcelona (University of Barcelona) Oct. 7, 2013 news release, which originated the news item, provides more details about the project,

Although Maxwell’s Demon is one of the cornerstones of theoretical statistical mechanisms, little has been done about its definite experimental realization. Marco Ribezzi, researcher from the Department of Fundamental Physics, explains that “the principal novelty of INFERNOS is to bring a robust and rigorous experimental base for this field of knowledge. We aim at creating a device that can use information to supply/extract energy to/from a system”. In this sense, the UB group, in which researcher Fèlix Ritort from the former department also participates, focuses their activity on understanding how information and temperature changes are used in individual molecules manipulation.

From the theory side, researchers will work in order to develop a theory of the fluctuation processes in small systems, which would then facilitate efficient algorithms for the Maxwell’s Demon operation.

INFERNOS is a three-year European project of the programme Future and Emerging Technologies (FET). Besides the University of Barcelona, INFERNOS partners are: Aalto University (Finland), project coordinator, Lund University (Sweden), the University of Oslo (Norway), Delf University of Technology (Netherlands), the National Center for Scientific Research (France) and the Research Foundation of State University of New York.

I like the INFERNOS logo, demon and all,

Logo of the European project INFERNOS (Information, fluctuations, and energy control in small systems).

Logo of the European project INFERNOS (Information, fluctuations, and energy control in small systems).

The INFERNOS project website can be found here.

And for anyone who finds that music is the best way to learn, here are Flanders & Swann* performing ‘First and Second Law’ from a 1964 show,

Enjoy!

* ‘Swan’ corrected to ‘Swann’ on April 1, 2014.

Designing nanocellulose (?) products in Finland; update on Canada’s CelluForce

A VTT Technical Research Centre of Finland Oct. 2, 2013 news release (also on EurekAlert) has announced an initiative which combines design with technical expertise in the production of cellulose- (nanocellulose?) based textile and other products derived from wood waste,

The combination of strong design competence and cutting-edge cellulose-based technologies can result in new commercially successful brands. The aim is for fibre from wood-based biomass to replace both cotton production, which burdens the environment, and polyester production, which consumes oil. A research project launched by VTT Technical Research Centre of Finland, Aalto University and Tampere University of Technology aims to create new business models and ecosystems in Finland through design-driven cellulose products.

The joint research project is called Design Driven Value Chains in the World of Cellulose (DWoC). The objective is to develop cellulose-based products suitable for technical textiles and consumer products. The technology could also find use in the pharmaceutical, food and automotive industries. Another objective is to build a new business ecosystem and promote spin-offs.

Researchers seek to combine Finnish design competence with cutting-edge technological developments to utilise the special characteristics of cellulose to create products that feature the best qualities of materials such as cotton and polyester. Product characteristics achieved by using new manufacturing technologies and nanocellulose as a structural fibre element include recyclability and individual production.

The first tests performed by professor Olli Ilkkala’s team at the Aalto University showed that the self-assembly of cellulose fibrils in wood permits the fibrils to be spun into strong yarn. VTT has developed an industrial process that produces yarn from cellulose fibres without the spinning process. VTT has also developed efficient applications of the foam forming method for manufacturing materials that resemble fabric.

“In the future, combining different methods will enable production of individual fibre structures and textile products, even by using 3D printing technology,” says Professor Ali Harlin from VTT.

Usually the price of a textile product is the key criterion even though produced sustainably. New methods help significantly to shorten the manufacturing chain of existing textile products and bring it closer to consumers to respond to their rapidly changing needs. Projects are currently under way where the objective is to replace wet spinning with extrusion technology. The purpose is to develop fabric manufacturing methods where several stages of weaving and knitting are replaced without losing the key characteristics of the textile, such as the way it hangs.

The VTT news release also provides statistics supporting the notion that cellulose textile products derived from wood waste are more sustainable than those derived from cotton,

Finland’s logging residue to replace environmentally detrimental cotton Cotton textiles account for about 40% of the world’s textile markets, and oil-based polyester for practically the remainder. Cellulose-based fibres make up 6% of the market. Although cotton is durable and comfortable to wear, cotton production is highly water-intensive, and artificial fertilisers and chemical pesticides are often needed to ensure a good crop. The surface area of cotton-growing regions globally equates to the size of Finland.

Approximately 5 million tons of fibre could be manufactured from Finland’s current logging residue (25 million cubic metres/year). This could replace more than 20% of globally produced cotton, at the same time reducing carbon dioxide emissions by 120 million tons, and releasing enough farming land to grow food for 18 million people. Desertification would also decrease by approximately 10 per cent.

I am guessing this initiative is focused on nanocellulose since the news release makes no mention of it but it is highly suggestive that one of the project leads, Olli Ilkkala mentions nanocellulose as part of the research for which he received a major funding award as recently as 2012,. From a Feb. 7, 2012 Aalto University news release announcing the grant for Ikkala’s research,

The European Research Council granted Aalto University’s Academy Professor Olli Ikkala funding in the amount of €2.3 million for research on biomimetic nanomaterials. Ikkala’s group specialises in the self-assembly of macromolecules and how to make use of this process when producing functional materials.

The interests of Ikkala’s group focus on the self-assembled strong and light nanocomposite structures found in nature, such as the nacreous matter underneath seashells and biological fibres resembling silk and nanocellulose. [emphasis mine] Several strong natural materials are built from both strong parallel elements and softening and viscosifying macromolecules. All sizes of structures form to combine opposite properties: strength and viscosity.

The research of the properties of biomimetic nanocomposites is based on finding out the initial materials of self-assembly. Initial material may include, for example, nano platelets, polymers, new forms of carbon, surfactants and nanocellulose.[emphasis mine]

– Cellulose is especially interesting, as it is the most common polymer in the world and it is produced in our renewable forests. In terms of strength, nano-sized cellulose fibres are comparable to metals, which was the very offset of interest in using nanocellulose in the design of strong self-assembled biomimetic materials, Ikkala says. [emphases mine]

Celluforce update

After reading about the Finnish initiative, I stumbled across an interesting little article on the Celluforce website about the current state of NCC (nanocrystalline cellulose aka CNC [cellulose nanocrystals]) production, Canada’s claim to fame in the nanocellulose world. From an August 2013 Natural Resources Canada, Canadian Forest Service, Spotlight series article,

The pilot plant, located at the Domtar pulp and paper mill in Windsor, Quebec, is a joint venture between Domtar and FPInnnovations called CelluForce. The plant, which began operations in January 2012, has since successfully demonstrated its capacity to produce NCC on a continuous basis, thus enabling a sufficient inventory of NCC to be collected for product development and testing. Operations at the pilot plant are temporarily on hold while CelluForce evaluates the potential markets for various NCC applications with its stockpiled material. [emphasis mine]

When the Celluforce Windsor, Québec plant was officially launched in January 2012 the production target was for 1,000 kg (1 metric ton) per day (there’s more in my Jan. 31 2012 posting about the plant’s launch). I’ve never seen anything which confirms they reached their production target, in any event, that seems irrelevant in light of the ‘stockpile’.

I am somewhat puzzled by the Celluforce ‘stockpile’ issue. On the one hand, it seems the planning process didn’t take into account demand for the material and, on the other hand, I’ve had a couple back channel requests from entrepreneurs about gaining access to the material after they were unsuccessful with Celluforce.  Is there not enough demand and/or is Celluforce choosing who or which agencies are going to have access to the material?

ETA Oct. 14, 2013: It took me a while to remember but there was a very interesting comment by Tim Harper (UK-based, emerging technologies consultant [Cientifica]) in Bertrand Marotte’s May 6, 2012 Globe & Mail article (about NCC (from my May 8, 2012 posting offering some commentary about Marotte’s article),

Tim Harper, the CEO of London-based Cientifica, a consultant on advanced technologies, describes the market for NCC as “very much a push, without signs of any pull.”

It would seem the current stockpile confirms Harper’s take on NCC’s market situation. For anyone not familiar with marketing terminology, ‘pull’ means market demand. No one is asking to buy NCC as there are no applications requiring the product, so there is ‘no pull/no market demand’.

“Control my chirality, please,” said the carbon nanotube to the researchers

A combined Finnish, Russian, and Danish team have found a way to control the chirality of single-walled carbon nanotubes according to an Apr. 30, 2013 news item on Azonano,

An ultimate goal in the field of carbon nanotube research is to synthesise single-walled carbon nanotubes (SWNTs) with controlled chiralities. Twenty years after the discovery of SWNTs, scientists from Aalto University in Finland, A.M. Prokhorov General Physics Institute RAS in Russia and the Center for Electron Nanoscopy of Technical University of Denmark (DTU) have managed to control chirality in carbon nanotubes during their chemical vapor deposition synthesis.

The Aalto University Apr. 29, 2013 news release, which originated the news item, goes on to explain,

 Over the years, substantial progress has been made to develop various structure-controlled synthesis methods. However, precise control over the chiral structure of SWNTs has been largely hindered by a lack of practical means to direct the formation of the metal nanoparticle catalysts and their catalytic dynamics during tube growth.

– We achieved an epitaxial formation of Co nanoparticles by reducing a well-developed solid solution in CO, reveals Maoshuai He, a postdoctoral researcher at Aalto University School of Chemical Technology.

– For the first time, the new catalyst was employed for selective growth of SWNTs, adds senior staff scientist Hua Jiang from Aalto University School of Science.

By introducing the new catalysts into a conventional CVD reactor, the research team demonstrated preferential growth of semiconducting SWNTs (~90%) with an exceptionally high population of (6,5) tubes (53%) at 500 °C. Furthermore, they also showed a shift of the chiral preference from (6,5) tubes at 500 °C  to (7, 6) and (9, 4) nanotubes at 400 °C.

– These findings open new perspectives both for structural control of SWNTs and for elucidating their growth mechanisms, thus are important for the fundamental understanding of science behind nanotube growth, comments Professor Juha Lehtonen from Aalto University.

For anyone like me who needs a description of chirality, there’s this from Wikipedia,

Chirality (pron.: /kaɪˈrælɪtiː/) is a property of asymmetry important in several branches of science. The word chirality is derived from the Greek, χειρ (kheir), “hand”, a familiar chiral object.

An object or a system is chiral if it is not identical to its mirror image, that is, it cannot be superposed onto it. A chiral object and its mirror image are called enantiomorphs (Greek opposite forms) or, when referring to molecules, enantiomers. A non-chiral object is called achiral (sometimes also amphichiral) and can be superposed on its mirror image.

Human hands are perhaps the most universally recognized example of chirality: The left hand is a non-superimposable mirror image of the right hand; no matter how the two hands are oriented, it is impossible for all the major features of both hands to coincide.[2] This difference in symmetry becomes obvious if someone attempts to shake the right hand of a person using his left hand, or if a left-handed glove is placed on a right hand. In mathematics chirality is the property of a figure that is not identical to its mirror image.

One of the researchers notes why they, or anyone else, would want to control the chirality of carbon nanotubes, from the news release,

– Chirality defines the optical and electronic properties of carbon nanotubes, so controlling it is a key to exploiting their practical applications, says Professor Esko I. Kauppinen, the leader of the Nanomaterials Group in Aalto University School of Science.

ETA Apr. 30, 2013 at 4:20 pm PDT: Here’s a link to and a citation for the team’s published paper,

Chiral-Selective Growth of Single-Walled Carbon Nanotubes on Lattice-Mismatched Epitaxial Cobalt Nanoparticles by Maoshuai He, Hua Jiang, Bilu Liu, Pavel V. Fedotov, Alexander I. Chernov, Elena D. Obraztsova, Filippo Cavalca, Jakob B. Wagner, Thomas W. Hansen, Ilya V. Anoshkin, Ekaterina A. Obraztsova, Alexey V. Belkin, Emma Sairanen, Albert G. Nasibulin,  Juha Lehtonen, & Esko I. Kauppinen. Scientific Reports 3, Article number 1460  doi:10.1038/srep01460 Published15 March 2013

This article is open access.

Protein cages, viruses, and nanoparticles

The Dec. 19, 2012 news release on EurekAlert about a study published by researchers at Aalto University (Finland) describes a project where virus particles are combined with nanoparticles to create new metamaterials,

Scientists from Aalto University, Finland, have succeeded in organising virus particles, protein cages and nanoparticles into crystalline materials. These nanomaterials studied by the Finnish research group are important for applications in sensing, optics, electronics and drug delivery.

… biohybrid superlattices of nanoparticles and proteins would allow the best features of both particle types to be combined. They would comprise the versatility of synthetic nanoparticles and the highly controlled assembly properties of biomolecules.

The gold nanoparticles and viruses adopt a special kind of crystal structure. It does not correspond to any known atomic or molecular crystal structure and it has previously not been observed with nano-sized particles.

Virus particles – the old foes of mankind – can do much more than infect living organisms. Evolution has rendered them with the capability of highly controlled self-assembly properties. Ultimately, by utilising their building blocks we can bring multiple functions to hybrid materials that consist of both living and synthetic matter, Kostiainen [Mauri A. Kostiainen, postdoctoral researcher] trusts.

The article which has been published in Nature Nanotechnology is free,

Electrostatic assembly of binary nanoparticle superlattices using protein cages by Mauri A. Kostiainen, Panu Hiekkataipale, Ari Laiho, Vincent Lemieux, Jani Seitsonen, Janne Ruokolainen & Pierpaolo Ceci in Nature Nanotechnology (2012) doi:10.1038/nnano.2012.220  Published online 16 December 2012

There’s a video demonstrating the assembly,

From the YouTube page, here’s a description of what the video is demonstrating,

Aalto University-led research group shows that CCMV virus or ferritin protein cages can be used to guide the assembly of RNA molecules or iron oxide nanoparticles into three-dimensional binary superlattices. The lattices are formed through tuneable electrostatic interactions with charged gold nanoparticles.

Bravo and thank  you to  Kostiainen who seems to have written the news release and prepared all of the additional materials (image and video). There are university press offices that could take lessons from Kostiainen’s efforts to communicate about the work.

Nanocellulose at the American Chemical Society’s 243rd annual meeting

Nanocellulose seems to be one of the major topics at the ACS’s (Americal Chemical Society) 243rd annual meeting themed Chemistry of Life  in San Diego, California, March 25-29, 2012. From the March 25, 2012 news item on Nanowerk,

… almost two dozen reports in the symposium titled, “Cellulose-Based Biomimetic and Biomedical Materials,” that focused on the use of specially processed cellulose in the design and engineering of materials modeled after biological systems. Cellulose consists of long chains of the sugar glucose linked together into a polymer, a natural plastic–like material. Cellulose gives wood its remarkable strength and is the main component of plant stems, leaves and roots. Traditionally, cellulose’s main commercial uses have been in producing paper and textiles –– cotton being a pure form of cellulose. But development of a highly processed form of cellulose, termed nanocellulose, has expanded those applications and sparked intense scientific research. Nanocellulose consists of the fibrils of nanoscale diameters so small that 50,000 would fit across the width of the period at the end of this sentence.

“We are in the middle of a Golden Age, in which a clearer understanding of the forms and functions of cellulose architectures in biological systems is promoting the evolution of advanced materials,” said Harry Brumer, Ph.D., of Michael Smith Laboratories, University of British Columbia, Vancouver. He was a co-organizer of the symposium with J. Vincent Edwards, Ph.D., a research chemist with the Agricultural Research Service, U.S. Department of Agriculture in New Orleans, Louisiana. “This session on cellulose-based biomimetic and biomedical materials is really very timely due to the sustained and growing interest in the use of cellulose, particularly nanoscale cellulose, in biomaterials.”

One of the presenters has a very charming way of describing the nanocellulose product his team is working on (from the news item),

Olli Ikkala, Ph.D., [Aalto University, Finland] described the new buoyant material, engineered to mimic the water strider’s long, thin feet and made from an “aerogel” composed of the tiny nano-fibrils from the cellulose in plants. Aerogels are so light that some of them are denoted as “solid smoke. [emphasis mine]” The nanocellulose aerogels also have remarkable mechanical properties and are flexible.

There were some 20 presentations in this symposium held under the auspices of the ACS annual meeting. Here’s a few of the presentations (some of these folks have been featured on this blog previously), from the news item,

Native cellulose nanofibers: From biomimetic nanocomposites to functionalized gel spun fibers and functional aerogels Olli Ikkala, Professor, PhD, Aalto University, P.O. Box 5100, Espoo, Finland, FIN-02015, Finland , 358-9-470 23154, [email protected] Native cellulose nanofibers and whiskers attract interest even beyond the traditional cellulose community due to their mechanical properties, availability and sustainability. We describe biomimetic nanocomposites with aligned self-assemblies combining nanocellulose with nanoclays, polymers, block copolymer, or graphene, allowing exciting mechanical properties. Functional ductile and even flexible aerogels are presented, combining superhydrophobicity, superoleophobicity, oil-spill absorption, photocatalytics, optically switchable water absorption, sensing, and antimicrobial properties. Finally mechanically excellent fibers are gel-spun and functionalized for electric, magnetic, optical and drug-release properties.

Evaluation of skin tissue repair materials from bacterial cellulose Lina Fu, Miss, Huazhong University of Science & Technology, College of Life Science & Technology, 1037 Luoyu Road, Wuhan, Hubei, 430074, China , 86-18971560696, [email protected] Bacterial cellulose (BC) has been reported as the materials in the tissue engineering fields, such as skin, bone, vascular and cartilage tissue engineering. Exploitation of the skin substitutes and modern wound dressing materials by using BC has attracted much attention. A skin tissue repair materials based on BC have been biosynthesized by Gluconacetobacter xylinus. The nano-composites of BC and chitosan form a cohesive gel structure, and the cell toxicity of the composite is excellent. Unlike other groups, which showed more inflammatory behavior, the inflammatory cells of the BC group were mainly polymorph-nuclear and showed few lymphocytes. The BC skin tissue repair material has an obviously curative effect in promoting the healing of epithelial tissue and reducing inflammation. With its superior mechanical properties, and the excellent biocompatibility, these skin tissue repair materials based on BC have great promise and potential for wound healing and very high clinical value.

….

New materials from nanocrystalline cellulose Mark MacLachlan [mentioned in my Nov. 18, 2010 posting], University of British Columbia, Department of Chemistry, 2036 Main Mall, Vancouver, BC, V6T 1Z1, Canada , 604-822-3070, [email protected] Nanocrystalline cellulose (NCC) is available from the acid-catalyzed degradation of cellulosic materials. NCC is composed of cylindrical crystallites with diameters of ca. 5-10 nm and large aspect ratios. This form of cellulose has intriguing properties, including its ability to form a chiral nematic structure. By using the chiral nematic organization of NCC as a template, we have been able to create highly porous silica films and carbon films with chiral nematic organization.1,2 These materials are iridescent and their structures mimic the shells of jewel beetles. In this paper, I will describe our recent efforts to use NCC to create new materials with interesting optical properties.

Factors influencing chiral nematic pitch and texture of cellulose nanocrystal films Derek G Gray, McGill University, Department of Chemistry, Pulp and Paper Building, 3420 University Street, Montreal, QC, H3A 2A7, Canada , 1-514-398-6182, [email protected] Appropriately stabilized cellulose nanocrystal (NCC) suspensions in water form chiral nematic liquid crystalline phases above some critical concentration. In the absence of added electrolye, the chiral nematic pitch of such suspensions is longer than that of visible light. Films prepared by evaporation from the suspensions also often display the characteristic fingerprint patterns characteristic of long-pitch chiral nematic phases, but the pitch values can be shifted into the visible range by adding small quantities of electrolyte to the evaporating suspension. The factors that control the final pitch have been the subject of some confusion. While still not well understood, it is clear that at high nanocrystal concentrations and in solid films, the pitch is not simply a reversible function of nanocrystal concentration. We examine some of the factors that control the pitch and liquid crystal texture during the drying of chiral nematic NCC films.

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Bioprinting of 3D porous nanocellulose scaffolds for tissue engineering and organ regeneration Paul Gatenholm, Professor, [mentioned in my March 19, 2012 posting] Wallenberg Wood Science Center, Chalmers, Department of Chemical and Biological Engineering, Kemigarden 4, Goteborg, V. Gotaland, SE41296, Sweden , 46317723407, [email protected] Nanocellulose is a promising biocompatible hydrogel like nano-biomaterial with potential uses in tissue engineering and regenerative medicine. Biomaterial scaffolds for tissue engineering require precise control of porosity, pore size, and pore interconnectivity. Control of scaffold architecture is crucial to promote cell migration, cell attachment, cell proliferation and cell differentiation. 3D macroporous nanocellulose scaffolds, produced by unique biofabrication process using porogens incorporated in the cultivation step, have shown ability to attract smooth muscle cells, endothelial cells, chondrocytes of various origins, urethral cells and osteoprogenitor cells. We have developed bioprinter which is able to produce 3D porous nanocellulose scaffolds with large size and unique architecture. Surface modifications have been applied to enhance cell adhesion and cell differentiation. In this study we have focused on use of 3D porous Nanocellulose scaffolds for stem cell differentiation into osteogenic and chondral lineages.