Monthly Archives: May 2015

Synthesizing spider silk

Most of the research on spider silk and spider webs that’s featured here is usually from the Massachusetts Institute of Technology (MIT) and, more specifically, from professor Markus J. Buehler. This May 28, 2015 news item on ScienceDaily, which heralds the development of synthetic spider silk, is no exception,

After years of research decoding the complex structure and production of spider silk, researchers have now succeeded in producing samples of this exceptionally strong and resilient material in the laboratory. The new development could lead to a variety of biomedical materials — from sutures to scaffolding for organ replacements — made from synthesized silk with properties specifically tuned for their intended uses.

The findings are published this week in the journal Nature Communications by MIT professor of civil and environmental engineering (CEE) Markus Buehler, postdocs Shangchao Lin and Seunghwa Ryu, and others at MIT, Tufts University, Boston University, and in Germany, Italy, and the U.K.

The research, which involved a combination of simulations and experiments, paves the way for “creating new fibers with improved characteristics” beyond those of natural silk, says Buehler, who is also the department head in CEE. The work, he says, should make it possible to design fibers with specific characteristics of strength, elasticity, and toughness.

The new synthetic fibers’ proteins — the basic building blocks of the material — were created by genetically modifying bacteria to make the proteins normally produced by spiders. These proteins were then extruded through microfluidic channels designed to mimic the effect of an organ, called a spinneret, that spiders use to produce natural silk fibers.

A May 28, 2015 MIT news release (also on EurekAlert), which originated the news item, describes the work in more detail,

While spider silk has long been recognized as among the strongest known materials, spiders cannot practically be bred to produce harvestable fibers — so this new approach to producing a synthetic, yet spider-like, silk could make such strong and flexible fibers available for biomedical applications. By their nature, spider silks are fully biocompatible and can be used in the body without risk of adverse reactions; they are ultimately simply absorbed by the body.

The researchers’ “spinning” process, in which the constituent proteins dissolved in water are extruded through a tiny opening at a controlled rate, causes the molecules to line up in a way that produces strong fibers. The molecules themselves are a mixture of hydrophobic and hydrophilic compounds, blended so as to naturally align to form fibers much stronger than their constituent parts. “When you spin it, you create very strong bonds in one direction,” Buehler says.

The team found that getting the blend of proteins right was crucial. “We found out that when there was a high proportion of hydrophobic proteins, it would not spin any fibers, it would just make an ugly mass,” says Ryu, who worked on the project as a postdoc at MIT and is now an assistant professor at the Korea Advanced Institute of Science and Technology. “We had to find the right mix” in order to produce strong fibers, he says.

The researchers made use of computational modelling to speed up the process of synthesizing proteins for synthetic spider silk, from the news release,

This project represents the first use of simulations to understand silk production at the molecular level. “Simulation is critical,” Buehler explains: Actually synthesizing a protein can take several months; if that protein doesn’t turn out to have exactly the right properties, the process would have to start all over.

Using simulations makes it possible to “scan through a large range of proteins until we see changes in the fiber stiffness,” and then home in on those compounds, says Lin, who worked on the project as a postdoc at MIT and is now an assistant professor at Florida State University.

Controlling the properties directly could ultimately make it possible to create fibers that are even stronger than natural ones, because engineers can choose characteristics for a particular use. For example, while spiders may need elasticity so their webs can capture insects without breaking, those designing fibers for use as surgical sutures would need more strength and less stretchiness. “Silk doesn’t give us that choice,” Buehler says.

The processing of the material can be done at room temperature using water-based solutions, so scaling up manufacturing should be relatively easy, team members say. So far, the fibers they have made in the lab are not as strong as natural spider silk, but now that the basic process has been established, it should be possible to fine-tune the materials and improve its strength, they say.

“Our goal is to improve the strength, elasticity, and toughness of artificially spun fibers by borrowing bright ideas from nature,” Lin says. This study could inspire the development of new synthetic fibers — or any materials requiring enhanced properties, such as in electrical and thermal transport, in a certain direction.

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

Predictive modelling-based design and experiments for synthesis and spinning of bioinspired silk fibres by Shangchao Lin, Seunghwa Ryu, Olena Tokareva, Greta Gronau, Matthew M. Jacobsen, Wenwen Huang, Daniel J. Rizzo, David Li, Cristian Staii, Nicola M. Pugno, Joyce Y. Wong, David L. Kaplan, & Markus J. Buehler. Nature Communications 6, Article number: 6892 doi:10.1038/ncomms7892 Published 28 May 2015

This paper is behind a paywall.

My two most recent (before this one) postings about Buehler’s work are an August 5, 2014 piece about structural failures and a June 4, 2014 piece about spiderwebs and music.

Finally, I recognized one of the authors, Nicola Pugno from Italy. He’s been mentioned here more than once in regard to his biomimicry work which has often been focused on geckos and their adhesive qualities as per this April 3, 2014 post announcing his book ‘An Experimental Study on Adhesive or Anti-Adhesive, Bio-Inspired Experimental Nanomaterials‘ (co-authored with Emiliano Lepore).

The nanostructure of cellulose at the University of Melbourne (Australia)

This is not the usual kind of nanocellulose story featured here as it doesn’t concern a nanocellulose material. Instead, this research focuses on the structure of cellulose at the nanoscale. From a May 21, 2015 news item on Nanotechnology Now,

Scientists from IBM Research and the Universities of Melbourne and Queensland have moved a step closer to identifying the nanostructure of cellulose — the basic structural component of plant cell walls.

The insights could pave the way for more disease resistant varieties of crops and increase the sustainability of the pulp, paper and fibre industry — one of the main uses of cellulose.

A May 21, 2015 University of Melbourne press release, which originated the news item, describes some of the difficulties of analyzing cellulose at the nanoscale and the role that IBM computer played in overcoming them,

Tapping into IBM’s supercomputing power, researchers have been able to model the structure and dynamics of cellulose at the molecular level.

Dr Monika Doblin, Research Fellow and Deputy Node Leader at the School of BioSciences at the University of Melbourne said cellulose is a vital part of the plant’s structure, but its synthesis is yet to be fully understood.

“It’s difficult to work on cellulose synthesis in vitro because once plant cells are broken open, most of the enzyme activity is lost, so we needed to find other approaches to study how it is made,” Dr Doblin said.

“Thanks to IBM’s expertise in molecular modelling and VLSCI’s computational power, we have been able to create models of the plant wall at the molecular level which will lead to new levels of understanding about the formation of cellulose.”

The work, which was described in a recent scientific paper published in Plant Physiology, represents a significant step towards our understanding of cellulose biosynthesis and how plant cell walls assemble and function.

The research is part of a longer-term program at the Victorian Life Sciences Computation Initiative (VLSCI) to develop a 3D computer-simulated model of the entire plant wall.

Cellulose represents one of the most abundant organic compounds on earth with an estimated 180 billion tonnes produced by plants each year.

A plant makes cellulose by linking simple units of glucose together to form chains, which are then bundled together to form fibres. These fibres then wrap around the cell as the major component of the plant cell wall, providing rigidity, flexibility and defence against internal and external stresses.

Until now, scientists have been challenged with detailing the structure of plant cell walls due to the complexity of the work and the invasive nature of traditional physical methods which often cause damage to the plant cells.

Dr John Wagner, Manager of Computational Sciences, IBM Research – Australia, called it a ‘pioneering project’.

“We are bringing IBM Research’s expertise in computational biology, big data and smarter agriculture to bear in a large-scale, collaborative Australian science project with some of the brightest minds in the field. We are a keen supporter of the Victorian Life Sciences Computation Initiative and we’re very excited to see the scientific impact this work is now having.”

Using the IBM Blue Gene/Q supercomputer at VLSCI, known as Avoca, scientists were able to perform the quadrillions of calculations required to model the motions of cellulose atoms.

The research shows that within the cellulose structure, there are between 18 and 24 chains present within an elementary microfibril, much less than the 36 chains that had previously been assumed.

IBM Researcher, Dr. Daniel Oehme, said plant walls are the first barrier to disease pathogens.

“While we don’t fully understand the molecular pathway of pathogen infection and plant r

You can find out more about this work and affiliated projects at the Australian Research Centre (ARC) of Excellence in Plant Cell Walls.

Egypt and enhanced oil recovery

Egypt and its nanotechnology efforts do pop up here from time to time. In this instance, there’s a bonus, the item in question concerns oil, a topic of some interest to Canadians, especially anyone who lives close to the oil sands and the province of Alberta.

Getting back to Egypt, a May 21, 2015 article by Rachel Williamson for WAMDA describes the energy situation in the country and research that may make a big difference (Note: Links have been removed),

Nanotechnology has been used in the oil and gas sector for decades, but in the last 15 years companies have been investing bigger sums than ever into the technology.

As Egypt struggles through an energy shortage, one scientist is hoping an entrepreneurial oil executive will notice – and utilize – his research on nanotechnology, and allow the field to finally take off in his country.

Dr. Adel Salem is only months into a new position at the brand new Future University in Cairo, where he heads research on ‘enhanced oil recovery,’ or EOR as it’s known in oil sector parlance, using nanoparticles.

That research could add 10-­20 percent more oil to Egypt’s current production, he believes, which has been in decline since 1996. That’s between 70,000 and 140,000 extra barrels of oil per day. To put that in context, total production in major gas operations in the Kurdistan region of Iraq has grown steadily to reach 70,000 barrels of oil equivalent per day.

Here’s a description of the science,

Salem is currently testing a sandstone core sample from an oil reservoir near the Bahariya formation in central Egypt. The plan is to find out the ultimate recovery factor using nanoparticles. These nanoparticles have been created from sand – silica – between one and 100 nanometers (very small). This nanomaterial is dissolved in a saltwater solution and the fluid is flushed through the core sample. The recovery factor from that experiment is compared to the same process using water and polymer flooding. Salem says the result is promising and could open a new era in enhanced oil recovery.

The researcher goes to provide more details about exactly how this material acts to increase recovery from an oil reservoir,

“If this is a bubble of oil and this is a solution containing some nano, for example, if this tiny particle moves with a certain force, it can invade this boundary interfacial tension [on the oil bubble], and another one invade here, and here… which means that at the end of the day it will break down the interfacial tension between the oil and water,” Salem said.

After the oil bubble is split into smaller droplets, the liquid can more easily move through the reservoir and into the well after it’s flooded once more with normal water.

Furthermore, nanoparticles ‘dissolved’ in steam have the ability to transfer heat from the earth’s surface down to the reservoir, which can make the oil less viscous and more likely to flow easily.

What this means is it’s easier to extract oil from a reservoir. It also means more oil can be extracted in a shorter period of time, reducing costs and allowing a company to use its equipment and staff more effectively.

“The challenges in this field are the size, the material type, and concentration of these nanoparticles. It’s a big challenge, the nano-material itself [be it] silica, aluminum, or zinc oxides,” Salem said. “The other is the concentration. We have to determine the optimum material, the optimum size, the optimum concentration, because all of these can provoke or can hinder or can damage the reservoir. For each reservoir people have to experiment to determine all of these factors.”

For the curious, Salem uses silicon nanoparticles purchased from China. Lab results show a 90% recovery rate which Salem suspects will translate to 50% – 60% in the field.

The researcher wants to commercialize this technology (from Williamson’s article),

… although Salem wants to commercialize his findings, regulations can prevent university staff from profiting from their research. He’s relying on an open-minded businessman or woman to realize the benefits of nanotechnology and introduce it to Egypt.

I recommend reading Williamson’s article in its entirety.

Testing for antibiotic resistance in one hour

University of Toronto researchers have devised a test for antibiotic resistance which cuts down the time from up to three days to one hour. From a May 27, 2015 news item on Azonano,

We live in fear of ‘superbugs’: infectious bacteria that don’t respond to treatment by antibiotics, and can turn a routine hospital stay into a nightmare. A 2015 Health Canada report estimates that superbugs have already cost Canadians $1 billion, and are a “serious and growing issue.” Each year two million people in the U.S. contract antibiotic-resistant infections, and at least 23,000 people die as a direct result.

But tests for antibiotic resistance can take up to three days to come back from the lab, hindering doctors’ ability to treat bacterial infections quickly. Now Ph.D. researcher Justin Besant and his team at the University of Toronto have designed a small and simple chip to test for antibiotic resistance in just one hour, giving doctors a shot at picking the most effective antibiotic to treat potentially deadly infections. Their work was published this week in the international journal Lab on a Chip.

A May 26, 2015 University of Toronto news release (also on EurekAlert), which originated the news item, provides more details about current testing regimes and about the new technique,

Resistant bacteria arise in part because of imprecise use of antibiotics—when a patient comes down with an infection, the doctor wants to treat it as quickly as possible. Samples of the infectious bacteria are sent to the lab for testing, but results can take two to three days. In the meantime, the doctor prescribes her patient a broad-spectrum antibiotic. Sometimes the one-size-fits-all antibiotic works and sometimes it doesn’t, and when the tests come back days later, the doctor can prescribe a specific antibiotic more likely to kill the bacteria.

“Guessing can lead to resistance to these broad-spectrum antibiotics, and in the case of serious infections, to much worse outcomes for the patient,” says Besant. “We wanted to determine whether bacteria are susceptible to a particular antibiotic, on a timescale of hours, not days.”

The problem with most current tests is the time it takes for bacteria to reproduce to detectable levels. Besant and his team, including his supervisor Professor Shana Kelley of the Institute for Biomaterials & Biomedical Engineering and the Faculties of Pharmacy and Medicine, and Professor Ted Sargent of The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, drew on their collective expertise in electrical and biomedical engineering to design a chip that concentrates bacteria in a miniscule space—just two nanolitres in volume—in order to increase the effective concentration of the starting sample.

They achieve this high concentration by ‘flowing’ the sample, containing the bacteria to be tested, through microfluidic wells patterned onto a glass chip. At the bottom of each well a filter, composed of a lattice of tiny microbeads, catches bacteria as the sample flows through. The bacteria accumulate in the nano-sized well, where they’re trapped with the antibiotic and a signal molecule called resazurin.

Living bacteria metabolize resazurin into a form called resorufin, changing its electrochemical signature. If the bacteria are effectively killed by the antibiotic, they stop metabolizing resazurin and the electrochemical signature in the sample stays the same. If they are antibiotic-resistant, they continue to metabolize resazurin into resorufin, altering its electrochemical signature. Electrodes built directly into the chip detect the change in current as resazurin changes to resorufin.

“This gives us two advantages,” says Besant. “One, we have a lot of bacteria in a very small space, so our effective starting concentration is much higher. And two, as the bacteria multiply and convert the resazurin molecule, it’s effectively stuck in this nanolitre droplet—it can’t diffuse away into the solution, so it can accumulate more rapidly to detectable levels.”

“Our approach is the first to combine this method of increasing sample concentration with a straightforward electrochemical readout,” says Professor Sargent. “We see this as an effective tool for faster diagnosis and treatment of commonplace bacterial infections.”

Rapid alternatives to existing antibiotic resistance tests rely on fluorescence detection, requiring expensive and bulky fluorescence microscopes to see the result.

“The electronics for our electrochemical readout can easily fit in a very small benchtop instrument, and this is something you could see in a doctor’s office, for example,” says Besant. “The next step would be to create a device that would allow you to test many different antibiotics at many different concentrations, but we’re not there yet.”

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

Rapid electrochemical phenotypic profiling of antibiotic-resistant bacteria by Justin D. Besant, Edward H. Sargent, and Shana O. Kelley. Lab Chip, 2015, Advance Article DOI: 10.1039/C5LC00375J First published online 13 May 2015

This paper is behind a paywall.

It was surprising to see Ted (Edward) Sargent mentioned with regard to a lab-on-a-chip project. I have featured research from him and from his laboratory many times here and, as I recall, it’s always been focused on solar cells. This Dec. 9, 2014 post features the latest research solar cell research that I’ve stumbled across from Sargent and the University of Toronto.

Pain in your blood—converting blood cells to neurons at McMaster University (Canada)

Having once spent several months doing a literature search on pain and morphine, I have a particular interest in this breakthrough from McMaster University (Canada) announced in a May 21, 2015 news item on ScienceDaily,

Scientists at McMaster University have discovered how to make adult sensory neurons from human patients simply by having them roll up their sleeve and providing a blood sample.

Specifically, stem cell scientists at McMaster can now directly convert adult human blood cells to both central nervous system (brain and spinal cord) neurons as well as neurons in the peripheral nervous system (rest of the body) that are responsible for pain, temperature and itch perception. This means that how a person’s nervous system cells react and respond to stimuli, can be determined from his blood.

A May 21, 2015 McMaster University news release on EurekAlert, which originated the news item, describes why this will make a difference for pain management,

Currently, scientists and physicians have a limited understanding of the complex issue of pain and how to treat it. The peripheral nervous system is made up of different types of nerves – some are mechanical (feel pressure) and others detect temperature (heat). In extreme conditions, pain or numbness is perceived by the brain using signals sent by these peripheral nerves.

“The problem is that unlike blood, a skin sample or even a tissue biopsy, you can’t take a piece of a patient’s neural system. It runs like complex wiring throughout the body and portions cannot be sampled for study,” said Bhatia [Mick Bhatia, director of the McMaster Stem Cell and Cancer Research Institute and much more].

“Now we can take easy to obtain blood samples, and make the main cell types of neurological systems – the central nervous system and the peripheral nervous system – in a dish that is specialized for each patient,” said Bhatia. “Nobody has ever done this with adult blood. Ever.

“We can actually take a patient’s blood sample, as routinely performed in a doctor’s office, and with it we can produce one million sensory neurons, that make up the peripheral nerves in short order with this new approach. We can also make central nervous system cells, as the blood to neural conversion technology we developed creates neural stem cells during the process of conversion.”

His team’s revolutionary, patented direct conversion technology has “broad and immediate applications,” said Bhatia, adding that it allows researchers to start asking questions about understanding disease and improving treatments such as: Why is it that certain people feel pain versus numbness? Is this something genetic? Can the neuropathy that diabetic patients experience be mimicked in a dish?

It also paves the way for the discovery of new pain drugs that don’t just numb the perception of pain. Bhatia said non-specific opioids used for decades are still being used today.

“If I was a patient and I was feeling pain or experiencing neuropathy, the prized pain drug for me would target the peripheral nervous system neurons, but do nothing to the central nervous system, thus avoiding non-addictive drug side effects,” said Bhatia.

“You don’t want to feel sleepy or unaware, you just want your pain to go away. But, up until now, no one’s had the ability and required technology to actually test different drugs to find something that targets the peripheral nervous system and not the central nervous system in a patient specific, or personalized manner.”

Bhatia’s team successfully tested their process using fresh blood, but also cryopreserved (frozen) blood. Since blood samples are taken and frozen with many clinical trials, this allows them “almost a bit of a time machine” to go back and explore questions around pain or neuropathy to run tests on neurons created from blood samples of patients taken in past clinical trials where responses and outcomes have already been recorded”.

In the future, the process may have prognostic potential, explained Bhatia, in that one might be able to look at a patient with Type 2 Diabetes and predict whether they will experience neuropathy by running tests in the lab using their own neural cells derived from their blood sample.

“This bench to bedside research is very exciting and will have a major impact on the management of neurological diseases, particularly neuropathic pain,” said Akbar Panju, medical director of the Michael G. DeGroote Institute for Pain Research and Care, a clinician and professor of medicine.

“This research will help us understand the response of cells to different drugs and different stimulation responses, and allow us to provide individualized or personalized medical therapy for patients suffering with neuropathic pain.”

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

Single Transcription Factor Conversion of Human Blood Fate to NPCs with CNS and PNS Developmental Capacity by Jong-Hee Lee, Ryan R. Mitchell, Jamie D. McNicol, Zoya Shapovalova, Sarah Laronde, Borko Tanasijevic, Chloe Milsom, Fanny Casado, Aline Fiebig-Comyn, Tony J. Collins, Karun K. Singh, and Mickie Bhatia.
Publication stage: In Press Corrected Proof Open Access DOI: http://dx.doi.org/10.1016/j.celrep.2015.04.056 Open access funded by the Author(s)

This is an open access paper. h/t Speaking Up For Science May 21, 2015 item

Research into nanosilver’s antibiotic properties and nanogold’s detection skills

There is a puzzling and exciting announcement from the Canadian Light Source in a May 27, 2015 news item on Nanowerk,

Precious metals like silver and gold have biomedical properties that have been used for centuries, but how do these materials effectively combat the likes of cancer and bacteria without contaminating the patient and the environment?

These are the questions that researchers from Dalhousie University and the Canadian Light Source are trying to find out.

Perhaps I’m misreading the announcement but the statement that nanosilver and nanogold don’t contaminate the patient or the environment is a bit exuberant. There are published studies examining questions about whether or not nanosilver may affect the environment and health and the answer is that no one is certain yet. You can read more about two studies highlighted in my February 28, 2013 posting titled:  Silver nanoparticles, water, the environment, and toxicity. As for nanosilver and nanogold not contaminating patients, that too is a problematic statement. For example, I have this paper which cites several studies on nanogold and possible toxicity. The paper itself is a plea to standardize testing and protocols so researchers can do a better job of establishing toxicity issues with nanogold.

GoldNP_ToxicityMar2015

Reservations aside, it’s good to learn of some Canadian research in this area. From a May 26, 2015 Canadian Light Source news release, which originated the news item, provides more details about the research and its current focus on nanosilver,

“Gold and silver are both exciting materials,” said Peng Zhang, Associate Professor of Chemistry at Dalhousie. “We can use gold to either detect or kill cancer cells. Silver is also excited and a very promising material as an antibacterial agents.”

Zhang said that if you compare silver to current antibiotics, silver does not show drug-resistant behaviour. “But with silver, so far, we are not finding that,” he added.

Finding out why silver is such a great antibacterial agent is the focus of Zhang’s research, recently published in the journal Langmuir.

“We want to understand the relationship between the atomic structure and bioactivity of nanosilver as to why it is so efficient at inhibiting bacterial activity. It’s a big puzzle.”

Zhang said it is very hard to understand what is happening at the atomic level. Using small nanosilver particles is the most effective way, because when you make silver small, you can expect higher activity because of the increased surface area.

This poses another problem however, as the nanosilver needs to be stabilized with a coating or the silver particles will bond together forming large pieces of silver that do not efficiently interact with the bacteria.

Zhang’s group used two different coatings to compare the effectiveness of the silver as an antibacterial agent. The first was a small amino acid coating and the other was a larger polymer coating. And after testing the interactions between the nanosilver and the bacteria, and looking at the atomic structure of nanosilver using the CLS and the Advanced Photon Source, the researchers were surprised to find that the thicker, larger polymer coating actually created a better delivery method for sliver to inhibit the bacteria.

“We proposed that the small amino acid coating would bind so tightly to the silver surface that it would be difficult for  the silver atoms to interact with the bacteria, whereas the polymers are actually very good at staying in place and still releasing sufficient amount of silver with the bacteria.”

Zhang said the next steps will be to find out if the nanosilver is actually attacking good cells in living systems before they can make any further progress on determining whether nanosilver is an effective and efficient antibactieral agent that could be used to cure human and animal diseases.

Here’s an illustration provided by the researchers,

The atomic structure of nanosilver, revealed by synchrotron X-ray spectroscopy, is proving to be a determinant of silver’s antibacterial activity. Padmos, J. Daniel, et al. "Impact of Protecting Ligands on Surface Structure and Antibacterial Activity of Silver Nanoparticles." Langmuir 31.12 (2015): 3745-3752.

The atomic structure of nanosilver, revealed by synchrotron X-ray spectroscopy, is proving to be a determinant of silver’s antibacterial activity.
Padmos, J. Daniel, et al. “Impact of Protecting Ligands on Surface Structure and Antibacterial Activity of Silver Nanoparticles.” Langmuir 31.12 (2015): 3745-3752.

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

Impact of Protecting Ligands on Surface Structure and Antibacterial Activity of Silver Nanoparticles by J. Daniel Padmos, Robert T. M. Boudreau, Donald F. Weaver, and Peng Zhang. Langmuir, 2015, 31 (12), pp 3745–3752
DOI: 10.1021/acs.langmuir.5b00049 Publication Date (Web): March 15, 2015

Copyright © 2015 American Chemical Society

This paper is behind a paywall.

Wood chip/computer chip, a cellulose nanofibril development

I imagine researchers at the University of Wisconsin-Madison and the US Department of Agriculture Forest Products Laboratory (FPL) are hoping they have managed to create a wood-based computer chip that can be commercialized in the near future. From a May 26, 2015 news item on ScienceDaily,

Portable electronics — typically made of non-renewable, non-biodegradable and potentially toxic materials — are discarded at an alarming rate in consumers’ pursuit of the next best electronic gadget.

In an effort to alleviate the environmental burden of electronic devices, a team of University of Wisconsin-Madison researchers has collaborated with researchers in the Madison-based U.S. Department of Agriculture Forest Products Laboratory (FPL) to develop a surprising solution: a semiconductor chip made almost entirely of wood.

The research team, led by UW-Madison electrical and computer engineering professor Zhenqiang “Jack” Ma, described the new device in a paper published today (May 26, 2015) by the journal Nature Communications. The paper demonstrates the feasibility of replacing the substrate, or support layer, of a computer chip, with cellulose nanofibril (CNF), a flexible, biodegradable material made from wood.

Here’s what the wood computer chip looks like,

A cellulose nanofibril (CNF) computer chip rests on a leaf. Photo: Yei Hwan Jung, Wisconsin Nano Engineering Device Laboratory

A cellulose nanofibril (CNF) computer chip rests on a leaf. Photo: Yei Hwan Jung, Wisconsin Nano Engineering Device Laboratory Courtesy University of Wisconsin-Madison

A May 25, 2015 University of Wisconsin-Madison news release by John Steeno, which originated the news item, provides more details,

“The majority of material in a chip is support. We only use less than a couple of micrometers for everything else,” Ma says. “Now the chips are so safe you can put them in the forest and fungus will degrade it. They become as safe as fertilizer.”

Zhiyong Cai, project leader for an engineering composite science research group at FPL, has been developing sustainable nanomaterials since 2009.

“If you take a big tree and cut it down to the individual fiber, the most common product is paper. The dimension of the fiber is in the micron stage,” Cai says. “But what if we could break it down further to the nano scale? At that scale you can make this material, very strong and transparent CNF paper.”

Working with Shaoqin “Sarah” Gong, a UW-Madison professor of biomedical engineering, Cai’s group addressed two key barriers to using wood-derived materials in an electronics setting: surface smoothness and thermal expansion.

“You don’t want it to expand or shrink too much. Wood is a natural hydroscopic material and could attract moisture from the air and expand,” Cai says. “With an epoxy coating on the surface of the CNF, we solved both the surface smoothness and the moisture barrier.”

Gong and her students also have been studying bio-based polymers for more than a decade. CNF offers many benefits over current chip substrates, she says.

“The advantage of CNF over other polymers is that it’s a bio-based material and most other polymers are petroleum-based polymers. Bio-based materials are sustainable, bio-compatible and biodegradable,” Gong says. “And, compared to other polymers, CNF actually has a relatively low thermal expansion coefficient.”

The group’s work also demonstrates a more environmentally friendly process that showed performance similar to existing chips. The majority of today’s wireless devices use gallium arsenide-based microwave chips due to their superior high-frequency operation and power handling capabilities. However, gallium arsenide can be environmentally toxic, particularly in the massive quantities of discarded wireless electronics.

Yei Hwan Jung, a graduate student in electrical and computer engineering and a co-author of the paper, says the new process greatly reduces the use of such expensive and potentially toxic material.

“I’ve made 1,500 gallium arsenide transistors in a 5-by-6 millimeter chip. Typically for a microwave chip that size, there are only eight to 40 transistors. The rest of the area is just wasted,” he says. “We take our design and put it on CNF using deterministic assembly technique, then we can put it wherever we want and make a completely functional circuit with performance comparable to existing chips.”

While the biodegradability of these materials will have a positive impact on the environment, Ma says the flexibility of the technology can lead to widespread adoption of these electronic chips.

“Mass-producing current semiconductor chips is so cheap, and it may take time for the industry to adapt to our design,” he says. “But flexible electronics are the future, and we think we’re going to be well ahead of the curve.”

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

High-performance green flexible electronics based on biodegradable cellulose nanofibril paper by Yei Hwan Jung, Tzu-Hsuan Chang, Huilong Zhang, Chunhua Yao, Qifeng Zheng, Vina W. Yang, Hongyi Mi, Munho Kim,    Sang June Cho, Dong-Wook Park, Hao Jiang, Juhwan Lee,    Yijie Qiu, Weidong Zhou, Zhiyong Cai, Shaoqin Gong, & Zhenqiang Ma. Nature Communications 6, Article number: 7170 doi:10.1038/ncomms8170 Published 26 May 2015

This paper is open access.

Synthetic Aesthetics update and an informal Canadian synthetic biology roundup

Amanda Ruggeri has written a very good introduction to synthetic biology for nonexperts in her May 20, 2015 Globe and Mail article about ‘Designing for the Sixth Extinction’, an exhibit showcasing designs and thought experiments focused on synthetic biology ,

In a corner of Istanbul’s Design Biennial late last year [2014], photographs of bizarre creatures sat alongside more conventional displays of product design and typefaces. Diaphanous globes, like transparent balloons, clung to the mossy trunk of an oak tree. Rust-coloured patterns ran across green leaves, as if the foliage had been decorated with henna. On the forest floor, a slug-like creature slithered, its back dotted with gold markings; in another photograph, what looked like a porcupine without a head crawled over the dirt, its quills tipped blood-red.

But as strange as the creatures looked, what they actually are is even stranger. Not quite living things, not quite machines, these imagined prototypes inhabit a dystopic, future world – a world in which they had been created to solve the problems of the living. The porcupine, for example, is an Autonomous Seed Disperser, described as a device that would collect and disperse seeds to increase biodiversity. The slug would be programmed to seek out acidic soils and neutralize them by dispersing an alkali hygroscopic fluid.

They are the designs – and thought experiments – of London-based Alexandra Daisy Ginsberg, designer, artist and lead author of the book Synthetic Aesthetics: Investigating Synthetic Biology’s Designs on Nature. In her project Designing for the Sixth Extinction, which after Istanbul is now on display at the Design Museum in London, Ginsberg imagines what a synthetic biology-designed world would look like – and whether it’s desirable. “

I have a couple of comments. First, the ‘Synthetic Aesthetics: Investigating Synthetic Biology’s Designs on Nature’ book launch last year was covered here in a May 5, 2014 post. where you’ll notice a number of the academics included in Ruggeri’s article are contributors to the book (but not mentioned as such). Second, I cannot find ‘Design for the Sixth Extinction’ listed as an exhibition on London’s Design Museum website.

Getting back to the matter at hand, not all of the projects mentioned in Ruggeri’s article are ‘art’ projects, there is also this rather practical and controversial initiative,

Designing even more complex organisms is the inevitable, and controversial, next step. And those designs have already begun. The British company Oxitec has designed a sterile male mosquito. When the bugs are released into nature and mate, no offspring result, reducing the population or eliminating it altogether. This could be a solution to dengue fever, a mosquito-carried disease that infects more than 50 million people each year: In field trials in Cayman, Panama and Brazil, the wild population of the dengue-carrying mosquito species was reduced by 90 per cent. Yet, as a genetically engineered solution, it also makes some skittish. The consequences of such manipulations remain unforeseen, they say. Proponents counter that the solution is more elegant, and safer, than the current practice of spraying chemicals.

Even so, the engineered mosquito leads to overarching questions: What are the dangers of tinkering with life? Could this cause a slide toward eugenics? Currently, the field doesn’t have an established ethics oversight process, something some critics are pushing to change.

It’s a surprising piece for the Globe and Mail newspaper to run since it doesn’t have a Canadian angle to it and the Globe and Mail doesn’t specialize in science (not withstanding Ivan Semeniuk’s science articles) or art/science or synthetic biology writing, for that matter. Perhaps it bodes an interest and more pieces on emerging science and technology and on art/science projects?

In any event, it seems like a good time to review some of the synthetic biology work or the centres of activity in Canada.  I believe the last time I tackled this particular topic was in a May 24, 2010 post titled, Canada and synthetic biology in the wake of the first ‘synthetic’ bacteria.

After a brief search, I found three centres for research:

Concordia [University] Centre for Applied Synthetic Biology (CASB)

[University of Toronto] The Synthetic Biology and Cellular Control Lab

[University of British Columbia] Centre for High-Throughput Biology (CHiBi)

Following an Oct. 27 – 28, 2014 UK-Canada Synthetic Biology Workshop held at Concordia University, Rémi Quirion, Vincent Martin, Pierre Meulien and Marc LePage co-wrote a Nov. 4, 2014 Concordia University post titled, How Canada is poised to revolutionize synthetic biology,

Rémi Quirion is the Chief Scientist of Québec, Fonds de recherche du Québec. Vincent Martin is Canada Research Chair in Microbial Genomics and Engineering and a professor in the Department of Biology at Concordia University in Montreal. Pierre Meulien is President and CEO of Genome Canada. Marc LePage is the President and CEO of Génome Québec.

Canada’s research and business communities have an opportunity to become world leaders in a burgeoning field that is fast shaping how we deal with everything from climate change to global food security and the production of lifesaving medications. The science of synthetic biology has the transformative capacity to equip us with novel technology tools and products to build a more sustainable society, while creating new business and employment opportunities for the economy of tomorrow.

We can now decipher the code of life for any organism faster and less expensively than ever before. Canadian scientists are producing anti-malarial drugs from organic materials that increase the availability and decrease the cost of lifesaving medicines. They are also developing energy efficient biofuels to dramatically reduce environmental and manufacturing costs, helping Canadian industry to thrive in the global marketplace.

The groundwork has also been laid for a Canadian revolution in the field. Canada’s scientific community is internationally recognized for its leadership in genomics research and strong partnerships with key industries. Since 2000, Genome Canada and partners have invested more than $2.3 billion in deciphering the genomes of economically important plants, animals and microbes in order to understand how they function. A significant proportion of these funds has been invested in building the technological toolkits that can be applied to synthetic biology.

But science cannot do it alone. Innovation on this scale requires multiple forms of expertise in order to be successful. Research in law, business, social sciences and humanities is vital to addressing questions of ethics, supply chain management, social innovation and cultural adaptation to new technologies. Industry knowledge and investments, as well as the capacity to incentivize entrepreneurship, are key to devising business models that will enable new products to thrive. Governments and funding agencies also need to do their part by supporting multidisciplinary research, training and infrastructure.

It’s a bit ‘hype happy’ for my taste but it does provide some fascinating insight in what seems to be a male activity in Canada.

Counterbalancing that impression is an Oct. 6, 2013 article by Ivan Semeniuk for the Globe and Mail about a University of Lethbridge team winning the top prize in a synthetic biology contest,

If you want to succeed in the scientific revolution of the future, it helps to think about life as a computer program.

That strategy helped University of Lethbridge students walk away with the top prize in a synthetic biology competition Sunday. Often touted as the genetic equivalent of the personal computer revolution, synthetic biology involves thinking about cells as programmable machines that can be designed and built to suit a particular need – whether it’s mass producing a vaccine or breaking down a hazardous chemical in the environment.

The five member Lethbridge team came up with a way to modify how cells translate genetic information into proteins. Rather than one bit of DNA carrying the information to make one protein – the usual way cells go about their business – the method involves inserting a genetic command that jiggles a cell’s translational machinery while it’s in mid-operation, coaxing it to produce two proteins out of the same DNA input.

“We started off with a computer analogy – kind of like zipping your files together – so you’d zip two protein sequences together and therefore save space,” said Jenna Friedt, a graduate student in biochemistry at Lethbridge. [emphasis mine]

There are concerns other than gender issues, chief amongst them, ethics. The Canadian Biotechnology Action Network maintains an information page on Synthetic Biology which boasts this as its latest update,

October 2014: In a unanimous decision of 194 countries, the United Nation’s Convention on Biological Diversity formally urged countries to regulate synthetic biology, a new extreme form of genetic engineering. The landmark decision follows ten days of hard-fought negotiations between developing countries and a small group of wealthy biotech-friendly economies. Until now, synthetic organisms have been developed and commercialized without international regulations. …

Finally, there’s a June 2014 synthetic biology timeline from the University of Ottawa’s Institute for Science, Society, and Policy (ISSP) which contextualizes Canadian research, policy and regulation with Australia, the European Union, the UK, and the US.

(On a closely related note, there’s my May 14, 2015 post about genetic engineering and newly raised concerns.)

US White House establishes new initiatives to commercialize nanotechnology

As I’ve noted several times, there’s a strong push in the US to commercialize nanotechnology and May 20, 2015 was a banner day for the efforts. The US White House announced a series of new initiatives to speed commercialization efforts in a May 20, 2015 posting by Lloyd Whitman, Tom Kalil, and JJ Raynor,

Today, May 20 [2015], the National Economic Council and the Office of Science and Technology Policy held a forum at the White House to discuss opportunities to accelerate the commercialization of nanotechnology.

In recognition of the importance of nanotechnology R&D, representatives from companies, government agencies, colleges and universities, and non-profits are announcing a series of new and expanded public and private initiatives that complement the Administration’s efforts to accelerate the commercialization of nanotechnology and expand the nanotechnology workforce:

  • The Colleges of Nanoscale Science and Engineering at SUNY Polytechnic Institute in Albany, NY and the National Institute for Occupational Safety and Health are launching the Nano Health & Safety Consortium to advance research and guidance for occupational safety and health in the nanoelectronics and other nanomanufacturing industry settings.
  • Raytheon has brought together a group of representatives from the defense industry and the Department of Defense to identify collaborative opportunities to advance nanotechnology product development, manufacturing, and supply-chain support with a goal of helping the U.S. optimize development, foster innovation, and take more rapid advantage of new commercial nanotechnologies.
  • BASF Corporation is taking a new approach to finding solutions to nanomanufacturing challenges. In March, BASF launched a prize-based “NanoChallenge” designed to drive new levels of collaborative innovation in nanotechnology while connecting with potential partners to co-create solutions that address industry challenges.
  • OCSiAl is expanding the eligibility of its “iNanoComm” matching grant program that provides low-cost, single-walled carbon nanotubes to include more exploratory research proposals, especially proposals for projects that could result in the creation of startups and technology transfers.
  • The NanoBusiness Commercialization Association (NanoBCA) is partnering with Venture for America and working with the National Science Foundation (NSF) to promote entrepreneurship in nanotechnology.  Three companies (PEN, NanoMech, and SouthWest NanoTechnologies), are offering to support NSF’s Innovation Corps (I-Corps) program with mentorship for entrepreneurs-in-training and, along with three other companies (NanoViricides, mPhase Technologies, and Eikos), will partner with Venture for America to hire recent graduates into nanotechnology jobs, thereby strengthening new nanotech businesses while providing needed experience for future entrepreneurs.
  • TechConnect is establishing a Nano and Emerging Technologies Student Leaders Conference to bring together the leaders of nanotechnology student groups from across the country. The conference will highlight undergraduate research and connect students with venture capitalists, entrepreneurs, and industry leaders.  Five universities have already committed to participating, led by the University of Virginia Nano and Emerging Technologies Club.
  • Brewer Science, through its Global Intern Program, is providing more than 30 students from high schools, colleges, and graduate schools across the country with hands-on experience in a wide range of functions within the company.  Brewer Science plans to increase the number of its science and engineering interns by 50% next year and has committed to sharing best practices with other nanotechnology businesses interested in how internship programs can contribute to a small company’s success.
  • The National Institute of Standards and Technology’s Center for Nanoscale Science and Technology is expanding its partnership with the National Science Foundation to provide hands-on experience for students in NSF’s Advanced Technology Education program. The partnership will now run year-round and will include opportunities for students at Hudson Valley Community College and the University of the District of Columbia Community College.
  • Federal agencies participating in the NNI [US National Nanotechnology Initiative], supported by the National Nanotechnology Coordination Office [NNCO], are launching multiple new activities aimed at educating students and the public about nanotechnology, including image and video contests highlighting student research, a new webinar series focused on providing nanotechnology information for K-12 teachers, and a searchable web portal on nano.gov of nanoscale science and engineering resources for teachers and professors.

Interestingly, May 20, 2015 is also the day the NNCO held its second webinar for small- and medium-size businesses in the nanotechnology community. You can find out more about that webinar and future ones by following the links in my May 13, 2015 posting.

Since the US White House announcement, OCSiAl has issued a May 26, 2015 news release which provides a brief history and more details about its newly expanded NanoComm program,

OCSiAl launched the iNanoComm, which stands for the Integrated Nanotube Commercialization Award, program in February 2015 to help researchers lower the cost of their most promising R&D projects dedicated to SWCNT [single-walled carbon nanotube] applications. The first round received 33 applications from 28 university groups, including The Smalley-Curl Center for Nanoscale Science and Technology at Rice University and the Concordia Center for Composites at Concordia University [Canada] among others. [emphasis mine] The aim of iNanoComm is to stimulate universities and research organizations to develop innovative market products based on nano-augmented materials, also known as clean materials.

Now the program’s criteria are being broadened to enable greater private sector engagement in potential projects and the creation of partnerships in commercializing nanotechnology. The program will now support early stage commercialization efforts connected to university research in the form of start-ups, technology transfers, new businesses and university spinoffs to support the mass commercialization of SWCNT products and technologies.

The announcement of the program’s expansion took place at the 2015 Roundtable of the US NanoBusiness Commercialization Association (NanoBCA), the world’s first non-profit association focused on the commercialization of nanotechnologies. NanoBCA is dedicated to creating an environment that nurtures research and innovation in nanotechnology, promotes tech-transfer of nanotechnology from academia to industry, encourages private capital investments in nanotechnology companies, and helps its corporate members bring innovative nanotechnology products to market.

“Enhancing iNanoComm as a ‘start-up incubator’ is a concrete step in promoting single-wall carbon nanotube applications in the commercial world,” said Max Atanassov, CEO of OCSiAl USA. “It was the logical thing for us to do, now that high quality carbon nanotubes have become broadly available and are affordably priced to be used on a mass industrial scale.”

Vince Caprio, Executive Director of NanoBCA, added that “iNanoComm will make an important contribution to translating fundamental nanotechnology research into commercial products. By facilitating the formation of more start-ups, it will encourage more scientists to pursue their dreams and develop their ideas into commercially successful businesses.”

For more information on the program expansion and how it can reduce the cost of early stage research connected to university projects, visit the iNanoComm website at www.inanocomm.org or contact info@inanocomm.org.

h/t Azonano May 27, 2015 news item

Good enough for the real world? A new device consisting of a singular molecule

While molecular diodes (a diode consisting of a single molecule) have been developed before, Columbia University’s Latha Venkataraman and her team have developed a new technique which may take these devices from the lab to real life. From a May 25, 2015 news item on Nanotechnology Now,

Under the direction of Latha Venkataraman, associate professor of applied physics at Columbia Engineering, researchers have designed a new technique to create a single-molecule diode, and, in doing so, they have developed molecular diodes that perform 50 times better than all prior designs. Venkataraman’s group is the first to develop a single-molecule diode that may have real-world technological applications for nanoscale devices.

A May 25, 2015 Columbia University news release on EurekAlert, which originated the news item, describes the new technique in greater detail,

“Our new approach created a single-molecule diode that has a high (>250) rectification and a high “on” current (~ 0.1 micro Amps),” says Venkataraman. “Constructing a device where the active elements are only a single molecule has long been a tantalizing dream in nanoscience. This goal, which has been the ‘holy grail’ of molecular electronics ever since its inception with Aviram and Ratner’s 1974 seminal paper, represents the ultimate in functional miniaturization that can be achieved for an electronic device.”

With electronic devices becoming smaller every day, the field of molecular electronics has become ever more critical in solving the problem of further miniaturization, and single molecules represent the limit of miniaturization. The idea of creating a single-molecule diode was suggested by Arieh Aviram and Mark Ratner who theorized in 1974 that a molecule could act as a rectifier, a one-way conductor of electric current. Researchers have since been exploring the charge-transport properties of molecules. They have shown that single-molecules attached to metal electrodes (single-molecule junctions) can be made to act as a variety of circuit elements, including resistors, switches, transistors, and, indeed, diodes. They have learned that it is possible to see quantum mechanical effects, such as interference, manifest in the conductance properties of molecular junctions.

Since a diode acts as an electricity valve, its structure needs to be asymmetric so that electricity flowing in one direction experiences a different environment than electricity flowing in the other direction. In order to develop a single-molecule diode, researchers have simply designed molecules that have asymmetric structures.

“While such asymmetric molecules do indeed display some diode-like properties, they are not effective,” explains Brian Capozzi, a PhD student working with Venkataraman and lead author of the paper. “A well-designed diode should only allow current to flow in one direction–the ‘on’ direction–and it should allow a lot of current to flow in that direction. Asymmetric molecular designs have typically suffered from very low current flow in both ‘on’ and ‘off’ directions, and the ratio of current flow in the two has typically been low. Ideally, the ratio of ‘on’ current to ‘off’ current, the rectification ratio, should be very high.”

In order to overcome the issues associated with asymmetric molecular design, Venkataraman and her colleagues–Chemistry Assistant Professor Luis Campos’ group at Columbia and Jeffrey Neaton’s group at the Molecular Foundry at UC Berkeley–focused on developing an asymmetry in the environment around the molecular junction. They created an environmental asymmetry through a rather simple method–they surrounded the active molecule with an ionic solution and used gold metal electrodes of different sizes to contact the molecule.

Their results achieved rectification ratios as high as 250: 50 times higher than earlier designs. The “on” current flow in their devices can be more than 0.1 microamps, which, Venkataraman notes, is a lot of current to be passing through a single-molecule. And, because this new technique is so easily implemented, it can be applied to all nanoscale devices of all types, including those that are made with graphene electrodes.

“It’s amazing to be able to design a molecular circuit, using concepts from chemistry and physics, and have it do something functional,” Venkataraman says. “The length scale is so small that quantum mechanical effects are absolutely a crucial aspect of the device. So it is truly a triumph to be able to create something that you will never be able to physically see and that behaves as intended.”

She and her team are now working on understanding the fundamental physics behind their discovery, and trying to increase the rectification ratios they observed, using new molecular systems.

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

Single-molecule diodes with high rectification ratios through environmental control by Brian Capozzi, Jianlong Xia, Olgun Adak, Emma J. Dell, Zhen-Fei Liu, Jeffrey C. Taylor, Jeffrey B. Neaton, Luis M. Campos, & Latha Venkataraman. Nature Nanotechnology (2015) doi:10.1038/nnano.2015.97 Published online 25 May 2015

This paper is behind a paywall but a free preview is available via ReadCube Access.