Tag Archives: American Chemical Society

GUMBOS, the nanoparticle kind

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The American Chemical Society (ACS) has posted its latest episode (GUMBOS; an interview with Isiah Warner) of the Prized Science podcast series according to a Nov. 19, 2013 news release on EurekAltert,

A group of nanoparticles called “GUMBOS” is as varied as their culinary namesake implies, with a wide range of potential applications from cancer therapy to sensors. GUMBOS are the focus of a new video from the American Chemical Society’s (ACS) Prized Science series. The videos are available at http://www.acs.org/PrizedScience.

The latest episode of Prized Science features Isiah Warner, Ph.D., this year’s winner of the ACS Award in Analytical Chemistry, sponsored by the Battelle Memorial Institute. He is a Boyd Professor of Chemistry at Louisiana State University. Among other research, the award recognizes Warner’s work developing GUMBOS, which is an acronym for “Group of Uniform Materials Based on Organic Salts.” In the video, Warner explains that the versatility of these nanoparticles, which are about 1/100,000th of the width of a human hair, comes from the ability to mix, match and tailor them to specific features for which a researcher is looking.

The next and final episode in the 2013 series of Prized Science features Esther Takeuchi, Ph.D., winner of the E. V. Murphee Award in Industrial and Engineering Chemistry.

Other episodes feature Tim Swager, Ph.D., winner of the 2013 ACS Award for Creative Invention; Peter J. Stang, Ph.D., winner of the 2013 ACS Priestley Medal; Greg Robinson, Ph.D., winner of the 2013 F. Albert Cotton Award; and Shirley Corriher, winner of the 2013 James T. Grady-James H. Stack Award for Interpreting Chemistry for the Public.

ACS encourages educators, schools, museums, science centers, news organizations and others to embed Prized Science on their websites. The videos discuss scientific research in non-technical language for general audiences. New episodes in the series, which focuses on ACS’ 2013 national award recipients, will be issued periodically.

The 2013 edition of Prized Science features renowned scientists telling the story of their own research and its impact and potential impact on everyday life. Colorful graphics and images visually explain the award recipient’s research.

The ACS administers more than 60 national awards to honor accomplishments in chemistry and service to chemistry. The nomination process involves submission of forms, with winners selected by a committee consisting of ACS members who typically are technical experts in the nominee’s specific field of research.

Here is the GUMBOS podcast,


Here is the video description and full credit list provided by the ACS (from the YouTube page hosting the video).

Uploaded on Nov 18, 2013

A group of nanoparticles called “GUMBOS” is as varied as their culinary namesake implies, with a wide range of potential applications from cancer therapy to sensors. The latest episode of Prized Science features Isiah Warner, Ph.D., this year’s winner of the ACS Award in Analytical Chemistry. Among other research, the award recognizes Warner’s work developing GUMBOS, which is an acronym for “Group of Uniform Materials Based on Organic Salts.” In the video, Warner explains that the versatility of these nanoparticles, which are about 1/100,000th of the width of a human hair, comes from the ability to mix, match and tailor them to have the specific features that scientists might need for different applications.

Produced by the American Chemical Society
Video by XiaoZhi Lim
Animation by Sean Parsons

As far as I know, there’s only one song that features gumbo in its lyrics, Jambalaya by Hank Williams. Here’s a somewhat bouncy version by John Fogerty,

Enjoy!

Fear of chemistry or chemistry of fear?

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While there are some who quake at the thought of chemistry classes, there are those who use chemistry as a springboard for studying fear. To celebrate Hallowe’en and all things frightful, the American Chemical Society has produced a 4 min. 29 sec. video titled the Chemistry of Fear as part of its Bytesize Science podcast series,

If you go to the American Chemical Society webpage hosting Bytesize Science podcasts, you’ll find a video which features a videoabout a woman who has no fear.

Gold nanoparticles can make your hair brown

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The Jan. 2, 2013 news item on Nanowerk notes that scientists have been able to synthesize gold nanoparticles inside human hair (Note: A link has been removed),

In a discovery with applications ranging from hair dyeing to electronic sensors to development of materials with improved properties, scientists are reporting the first synthesis of gold nanoparticles inside human hairs. Their study appears in ACS’ journal Nano Letters (“Hair Fiber as a Nanoreactor in Controlled Synthesis of Fluorescent Gold Nanoparticles”).

The Jan. 2, 2012 press release from the American Chemical Society (ACS), which originated the news item, provides a few more details,

Philippe Walter and colleagues explain that gold nanoparticles — 40,000-60,000 of which could fit across the width of a human hair — are a hot topic. Scientists are exploring uses, ranging from electronics and sensors to medical diagnostic tests and cancer treatments. Gold nanoparticles have been deposited on hair for use as electrodes, and gold nanoparticles had been used to dye wool. Walter’s team looked at a new use — dyeing hair, inspired by the ancient Greeks’ and Romans’ use of another metal, lead, to color their hair.

They describe the first synthesis of fluorescent gold nanoparticles inside human hair. It involved soaking white hairs in a solution of a gold compound. The hairs turned pale yellow and then darkened to a deep brown. Using an electron microscope, the scientists confirmed that the particles were forming inside the hairs’ central core cortex. The color remained even after repeated washings.

The authors acknowledge funding from the Agence Nationale de la Recherche.

Here’s what the hair looks like,

Gold nanoparticles darken hair after treatment for one day, center, and 16 days, right (untreated hairs, left). Credit: American Chemical Society

Gold nanoparticles darken hair after treatment
for one day, center, and 16 days, right
(untreated hairs, left).
Credit: American Chemical Society

For anyone who wants to follow up further, there’s a citation for and link to the research paper,

Hair Fiber as a Nanoreactor in Controlled Synthesis of Fluorescent Gold Nanoparticles by Shrutisagar D. Haveli, Philippe Walter, Gilles Patriarche, Jeanne Ayache, Jacques Castaing, Elsa Van Elslande, Georges Tsoucaris, Ping-An Wang, and Henri B. Kagan in Nano Lett., 2012, 12 (12), pp. 6212-5217 DOI: 10.1021/nl303107w Publication Date (Web): Nov. 2, 2012 © 2012 American Chemical Society

This is paper is behind a paywall.

Ask and ye shall receive: a ‘communicating controversial science’ symposium

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Yesterday (Aug. 21, 2012), I expressed the hope (in my Repairing your vocal cords posting) that the American Chemical Society’s (ACS) 244th meeting would provide a session or two to counterbalance the relentless science enthusiasm (it’s like cooking where you need to add  a little salt to balance the sugar in your cake).

Providentially, the Aug. 21, 2012 (I often get the notices a day later) news release on EurekAlert announced a special symposium on controversial science being held at the Fall 2012 meeting,

The American Chemical Society (ACS), the world’s largest scientific society, is holding a special symposium today honoring Rudy M. Baum, editor-in-chief of its weekly newsmagazine, whose thought-provoking editorials and editorial leadership made Baum an icon among ACS’ more than 164,000 members.

“Rudy Baum’s editorials focused on some of the greatest challenges facing humanity,” said ACS President Bassam Z. Shakhashiri, Ph.D., who organized the symposium. It is part of the 244th ACS National Meeting & Exposition, a scientific extravaganza being held here through Thursday. The meeting features 8,600 reports on new discoveries in science and other topics, a major scientific exposition and an anticipated attendance of more than 14,000 scientists and others.

“Baum tackled inherently controversial topics ― global climate change, for instance, surging population growth, disease, violence and war and the denial of basic human rights,” added Shakhashiri, who is the William T. Evjue Distinguished Chair for the Wisconsin Idea at the University of Wisconsin-Madison. “Rudy had the courage to express his opinions forthrightly and honestly. He has challenged us all to be scientist-citizens for the benefit of Earth and its people.”

The news releases lists a number of presentations included as part of the symposium,

Abstracts

Every Day in Every Way, Chemistry Makes the World Ever Better
Richard N. Zare, Marguerite Blake Wilbur Professor in Natural Science, Stanford University

Such were not the titles or contents of Rudy Baum’s editorials in Chemical & Engineering News, although many of my friends had wished otherwise. Instead, Rudy followed a far riskier path of provoking thought and broaching controversial topics. Whether you agreed or disagreed with his points of view, they raised the level of discourse about the role of chemistry in society. Let me congratulate Rudy Baum on his many years of editorship of the flagship weekly of the American Chemical Society. He always made it clear to his readers that he was speaking for himself, not the Society, and I applaud his boldness and daring. The turtle only advances by sticking its neck out.

It’s Not Just About the Science
Eugenie Scott, Executive Director, The National Center for Science Education (NCSE)

The National Center for Science Education defends the teaching of evolution and climate change, two topics on which there is considerable scientific consensus but strong ideological pushback from the general public. How does one change the perception of the public to more closely parallel that of scientists? The normal reaction of scientists is to bemoan the quality of science education, and propose that more and better science instruction will solve the problem. However, multifactorial problems require multifactorial solutions, and the rejection by substantial proportion of the public of well-established science is certainly multifactorial. We need to go beyond science (and science education) to consider the underlying ideological sources of the rejection and how best to deal with them.

Where in the World Will Our Energy Come From?
Nate Lewis, George L. Argyros Professor of Chemistry, California Institute of Technology

Where in the world will our energy come from? What would it take for the world to get away from fossil fuels and switch over to renewable energy? It takes more than willingness to buy a Prius or to have solar panels installed on your roof. If we want to use wind, solar thermal, solar electric, biomass, hydroelectric and geothermal energy it will take a lot of planning, and willingness on the part of governments and industry. It takes R&D investment, a favorable price per unit of energy to get anyone to produce alternative energy, and plenty of resources to create those energy sources.

Lewis will discuss these and other hurdles – technical, political, and economic – that must be overcome before the widespread adoption of renewable energy technologies.

Odds Are It’s Wrong: How Misuse of Statistics Fuels Scientific Controversy
Tom Siegfried, Editor-in-Chief, Science News

Standard tests of statistical significance are widely recognized to be deeply flawed, but are nevertheless widely used in scientific studies. Far from merely a technical concern, this issue is literally a matter of life and death. Misuse of statistics generates controversies about the safety of medicines such as antidepressants that end up depriving some people of life-saving treatments. Media coverage of such issues — and scientific results in general — is confounded by the diabolical coincidence that the qualities of a scientific finding that make it newsworthy are also the qualities that render it most susceptible to being a statistical illusion.

Beware! Breaking a Paradigm can Result in Pain and Suffering
Chris Enke, Professor of Chemistry (Retired), University of New Mexico

Innovators who overturn established paradigms frequently encounter antipathy (or worse) from their scientific communities. I believe a principal cause of this reaction is confusion over which parts of scientific knowledge are facts and which are theories subject to change. We rely on verified observations and established relationships to be true and repeatable within given boundaries. However, the explanations we conceive for these relationships, even though experimentally and theoretically supported to various degrees, are neither proven nor unique. Strong attachments to widely accepted explanations influence our responses to messengers bringing news of their demise.

Toxics, Carcinogens & Mutagens …..Oh My!
Glenn Ruskin, Director, Office of Public Affairs, American Chemical Society

Generally, people fear the unknown. The general public and media often struggle with highly complex scientific issues and topics, especially those with strange names, scary properties and controversy attached to them. When confronted with the unknown, most people will “take flight” – preferring to avoid the topic or issue. In many cases, people will look to experts or organizations they think they “trust” to help explain the issue to them. People want complex and controversial topics broken down into the simplest of terms so they can make informed decisions. Unless scientists or the presenters of complex and controversial science can effectively communicate with the media and general public – disastrous outcomes can result. This presentation will look at how scientific topics can effectively be presented to foster public understanding.

Why I Love A Good Poison
Deborah Blum, Helen Firstbrook Franklin Professor of Journalism, University of Wisconsin-Madison

Journalists, they say, are drawn to controversy. Or in my case, controversial – and often hazardous – chemical compounds. Some of this has to do with the way story-telling works – a writer needs theatre to make a story compelling. But in the case of science writers, like myself, we are usually looking for the “teachable moment” that goes with that controversy, that hazard, that highly readable tale. We can use such cases to delve into everything from peer review to the realities of observational studies. And a chemistry blogger like myself can use a good poison to illustrate much about how the science works – and whether it works well.

Reporting Ethical Violations In Research
William G. Schulz, News Editor, Chemical & Engineering News

A reporter’s notebook of stories that have covered a wide range of ethical violations, including one of the worst cases of scientific fraud ever. Research ethics stories often challenge journalists to hew to their own code of ethics and avoid the pitfalls that might threaten their own journalistic reputations.

The Hockey Stick and the Climate Wars: Dispatches From The Front Lines
Michael E. Mann, Director, Earth System Science Center, The Pennsylvania State University

A central figure in the controversy over human-caused climate change has been “The Hockey Stick,” a simple, easy-to-understand graph my colleagues and I constructed to depict changes in Earth’s temperature back to 1000 AD. The graph was featured in the high-profile “Summary for Policy Makers” of the 2001 report of the Intergovernmental Panel on Climate Change (IPCC), and it quickly became an icon in the debate over human-caused (“anthropogenic”) climate change. I will tell the story behind the Hockey Stick, using it as a vehicle for exploring broader issues regarding the role of skepticism in science, the uneasy relationship between science and politics, and the dangers that arise when special economic interests and those who do their bidding attempt to skew the discourse over policy-relevant areas of science. In short, I attempt to use the Hockey Stick to cut through the fog of disinformation that has been generated by the campaign to deny the reality of climate change. It is my intent, in so doing, to reveal the very real threat to our future that lies behind it.

Covering Controversial Science for C&EN
Rudy Baum, Editor-in-Chief, Chemical & Engineering News

Science is a system for understanding nature, the only system that yields testable knowledge. Since its inception, some of the knowledge uncovered by science has been controversial because it clashed with the revealed “truth” of religious beliefs. The most prominent such clash has been the controversy over Darwinian evolution that continues today. More recently, science has been controversial when it threatened economic interests as was the case with research that established a link between smoking and cancer, CFCs and stratospheric ozone depletion, and human activities and climate disruption. I have been reporting and commenting on controversial science throughout my 32-year career at C&EN and will draw from those experiences in my talk.

Other Talks in the Symposium

Is it ‘News’ if It Happens Slowly?
George M. Whitesides, Woodford L. and Ann A. Flowers University Professor, Harvard University

Communicating Science that People May Not Be Ready to Hear
Paul T. Anastas, Director, Center for Green Chemistry and Green Engineering, Teresa and H. John Heinz III Professor in the Practice of Chemistry for the Environment, School of Forestry & Environmental Studies, Yale University

Thanks for Writing
Bassam Z. Shakhashiri, President, American Chemical Society, Professor of Chemistry, University of Wisconsin-Madison

I wish I could have been there, this looks like a very interesting lineup. Perhaps some of our Canadian science conference organizers can take some inspiration from this symposium for future meetings here in Canada.

By the way, I notice that George Whitesides is listed (third from the bottom)  as one of the symposium presenters. Whitesides was last featured here in a posting titled, Watch out Roomba! Camouflaging soft robots are on the move (Aug. 17, 2012).

Solid smoke; a new generation of aerogels

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The latest American Chemical Society (244th) meeting (Fall 2012, Aug. 19 – 23, 2012) includes a presentation on one of my favourite topics ‘solid smoke’ or aerogel, as it’s called more commonly.

From the Aug. 19, 2012 news item on Nanowerk (Note: I have removed a reference to a video on previous generations of aerogels that the folks at Nanowerk found and included with this news item),

A major improvement in the world’s lightest solid material and best solid insulating material, described here today, may put more of this space-age wonder into insulated clothing, refrigerators with thinner walls that hold more food, building insulation and other products.

The report, on development of a new flexible “aerogel” — stuff so light it has been called “solid smoke” — was part of the 244th National Meeting & Exposition of the American Chemical Society, the world’s largest scientific society. …

Mary Ann B. Meador, Ph.D., explained that traditional aerogels, developed decades ago and made from silica, found in beach sand, are brittle, and break and crumble easily. Scientists have improved the strength of aerogels over the years, and Meador described one of these muscled-up materials developed with colleagues at the NASA Glenn Research Center in Cleveland, Ohio.

The Aug. 19, 2012 news release from the American Chemical Society, which originated the news item, describes this new generation of aerogels’ strength and potential applications,

“The new aerogels are up to 500 times stronger than their silica counterparts,” Meador said. “A thick piece actually can support the weight of a car. And they can be produced in a thin form, a film so flexible that a wide variety of commercial and industrial uses are possible.”

Flexible aerogels, for instance, could be used in a new genre of super-insulating clothing that keeps people warm in the cold with less bulk than traditional “thermal” garments. Tents and sleeping bags would have the same advantages. Home refrigerator and freezer walls insulated with other forms of the material would shrink in thickness, increasing storage capacity. Meador said that the aerogel is 5-10 times more efficient than existing insulation, with a quarter-inch-thick sheet providing as much insulation as 3 inches of fiberglass. And there could be multiple applications in thin-but-high-efficiency insulation for buildings, pipes, water heater tanks and other devices.

NASA envisions one use in an advanced re-entry system for spacecraft returning to Earth from the International Space Station, and perhaps other missions. Re-entry vehicles need a heat shield that keeps them from burning up due to frictional heating from Earth’s atmosphere. Those shields can be bulky and heavy. So NASA is exploring use of a heat shield made from flexible aerogel that inflates like a balloon when spacecraft enter the atmosphere.

Meador said the material also could be used to insulate spacesuits. However, it likely would not be good for firefighting clothing products, which require protection beyond the 575 degrees Fahrenheit limits of the aerogel.

The scientists also offered a brief explanation of how these new aerogels are made (from the ACS news release),

Scientists produced the stronger new aerogels in two ways. One involved making changes in the innermost architecture of traditional silica aerogels. They used a polymer, a plastic-like material, to reinforce the networks of silica that extend throughout an aerogel’s structure. Another involved making aerogels from polyimide, an incredibly strong and heat-resistant polymer, or plastic-like material, and then inserting brace-like cross-links to add further strength to the structure.

My last mention of ‘solid smoke’ was in my Mar.27, 2012 posting about the 243rd meeting of the American Chemical Society held in Spring 2012.

US chemists talk nano in a June 27, 2012 Washington, DC briefing

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The American Chemical Society (ACS) has a Science & the Congress Project where they provide information about various science and technology issues to policymakers. Their latest briefing will be on nanomaterials and the Toxic Substances Control Act.  From the June 21, 2012 news release on EurekAlert,

The American Chemical Society (ACS) Science & the Congress Project invites news media to attend a luncheon briefing on “Nanomaterial Safety: Do We Have the Right Tools?” It will be held Wednesday, June 27, 12-1:30 p.m., in the Russell Senate Office Building Room 325. To attend, register at http://tinyurl.com/ACSSciCongr-nanoEHS.

This briefing is hosted by the ACS Science & the Congress Project with honorary co-host the Congressional Nanotechnology Caucus.

With nanotechnology, scientists engineer materials on a molecular level; that is, they work with such basic factors as the size, shape and surface properties of substances, in addition to altering the chemical composition, to create materials that exhibit novel properties. While the science to engineer nanomaterials has been developed largely since the 1980s, public laws to regulate the safety of materials and chemicals, such as the Toxic Substances Control Act (TSCA), were crafted in the 1970s. Important questions for our times: Does our understanding of and information about nanotechnology adequately inform the policies designed to ensure safe product development? Likewise, do the current policies address both the possible problems and benefits associated with nanotechnology? This panel will discuss whether policymakers currently have the necessary tools, both scientific and policy mechanisms, to reap the potentials of nanotechnology.

The briefing will feature the following panelists and an open discussion:

Moderator: Kristen Kulinowski, Ph.D., Science and Technology Policy Institute, Institute for Defense Analyses

Panelists:

  • Lynn Bergeson, Bergeson & Campbell P.C.
  • Richard Denison, Ph.D., Environmental Defense Fund
  • Arturo Keller, Ph.D., University of California, Santa Barbara

For those of us who can’t attend, it is possible to find more information the Science &the Congress Project, from the About page (and if you keep reading you’ll find that you may still be able to access the briefing even if you can’t attend the real-time event),

Since 1995, the American Chemical Society (ACS) has operated the Science & the Congress Project to educate and inform Members of Congress and their staffs on the importance of science and technology to solving national challenges. The Science & the Congress Project has conducted well over 100 congressional briefings on important and timely policy topics, relying on panels of knowledgeable and diverse experts to provide comprehensive, balanced presentations about chosen topics, and to increase the level of scientific and technological literacy on Capitol Hill. The goals of the project include:

  • Highlighting the role of S&T in public policy.
  • Helping Members of Congress and their staffs gain a deeper knowledge of the science involved in policy issues.
  • Serving as a neutral and credible source of scientific information.
  • Promoting the responsible use of science in national policymaking.

Serving ACS and Its Members

The ACS Science & the Congress Project provides significant benefits for ACS and its members:

  • Balanced, nonpartisan briefings lend credibility to ACS policy efforts.
  • Initiation of briefings enhances ACS’s leadership role among peer organizations.
  • Collaborations with cosponsors enhance ACS’s ties and foster cooperation within the scientific community.
  • Online availability of briefing materials increases ACS members’ exposure to science policy topics.

Enhancing Relationships

During more than a decade of existence, the ACS Science & the Congress Project has conducted well over 100 briefings and built relationships with:

  • Congressional offices, committees, caucuses and staffers.
  • Experts in academia, non-governmental organizations and all levels of government.
  • Professional organizations with overlapping interests.

They also make their materials available after the briefing,

Serving as an Ongoing Source of Science Policy Information

Individual web pages for each Science & the Congress Project briefing provide a breadth of resources on the briefing’s topic, including:

  • The speakers’ presentations.
  • Speaker biographical and contact information.
  • Supplemental links, documents, and articles.

I checked and it is possible to access the briefings and other information without a subscription. I hope the nanomaterials briefing will be available soon on the website soon. Here’s the page you should check.

Cotton and nanotechnology at the US Dept. of Agriculture

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The April 2012 item by Jan Suszkiw of the US Dept. of Agriculture (on the Western Farm Press website) seemed strangely familiar as it focused on research into flame-retardant cotton. From the Suszkiw article,

In one ongoing project, the researchers have teamed with Texas A&M University scientists to evaluate a first-of-its-kind, environmentally friendly flame-retardant for cotton apparel and durable goods. Halogenated flame retardants have been among the most widely used chemical treatments, but there’s been a push to find alternatives that are more benign and that won’t cause treated fabric to stiffen, according to Condon [Brian Condon, Agricultural Research Service [ARS]).

I mentioned the research work in the context of a 2011 meeting of the American Chemical Society in my Sept. 6, 2011 posting (scroll down about 3/4 of the way) except the focus was on the Texas A&M University in College Station research team who had yet to collaborate with Condon’s team at the ARS,

In responding to the need for more environmentally friendly flame retardants, Grunlan’s [Jaime C. Grunlan] team turned to a technology termed “intumescence,” long used to fireproof exposed interior steel beams in buildings. At the first lick of a flame, an intumescent coating swells up and expands like beer foam, forming tiny bubbles in a protective barrier that insulates and shields the material below. The researchers are at Texas A&M University in College Station. …

Since the meeting last fall, the two teams (US ARS [Condon] and Texas A&M [Grunlan]) have collaborated to make cotton more flame retardant according to the April 2012 news article (Cotton Gets Nanotech and Biotech Treatment in New Orleans) on the US Dept. of Agriculture, Agricultural Research Service website (Note: I have removed a link),

Condon and CCUR (Cotton Chemistry and Utilization Research Unit) chemist SeChin Chang are collaborating with Texas A&M University (TAMU) scientists to evaluate a first-of-its-kind, environmentally friendly flame retardant for cotton apparel and durable goods.

Halogenated flame retardants have been among the most widely used chemical treatments for cotton. But there’s been a push to find alternatives that are not only more benign, but that also avoid imparting the same stiffness to fabric characteristic of some chemical treatments. For these and other reasons, “the textiles industry would like to move away from using halogenated flame retardants,” says Condon.

Made of water-soluble polymers, nanoscale clay particles, and other “green” ingredients, the ARS-TAMU flame retardant is applied as a nanocoating that reacts to open flame by rapidly forming a swollen, charred surface layer. This process, known as “intumescence,” stops the flame from reaching underlying or adjacent fibers.

A team led by Jaime Grunlan at TAMU’s Department of Mechanical Engineering, in College Station, Texas, originally developed the intumescent nanocoating using a layer-by-layer assembly. In this procedure, alternating layers of positively and negatively charged ingredients, including clay particles 50-100 nanometers wide, are deposited onto the surface of a desired material. The result is a striated nanocoating that, when viewed under a scanning electron or other high-powered microscope, resembles the stacked layers of a brick wall.

Condon’s interest was piqued after listening to Grunlan discuss his team’s research at a recent American Chemical Society meeting, and he approached the TAMU professor about potential benefits to cotton. That conversation, in turn, led to a cooperative research project enabling Condon and Chang to evaluate the nanocoating at CCUR.

Treating cotton for flame resistance isn’t a recent concept, adds Condon, whose lab is part of the ARS Southern Regional Research Center in New Orleans. In fact, some of the most successful early treatments were born of research conducted by Benerito [Ruth Benerito] and colleagues there several decades ago. (See “Cross-Linking Cotton,” Agricultural Research, February 2009, pp. 10-11.) Condon coauthored a 2011 ACS Nano paper on the potential of intumescent coatings together with Chang, Grunlan and his TAMU team, and Alexander Morgan of the University of Dayton Research Institute in Ohio.

Early trials of the nanocoating using standard flame-resistance tests are promising. In one case, 95 percent of treated cotton fabric remained intact after exposure to flame, whereas the untreated fabric used for comparison was completely destroyed

“What we’re investigating now is how well it will perform after repeated launderings of treated fabric,” says Condon. “After all, the coating contains clay, and that’s something detergents are made to remove.”

Even if the coating does eventually wash out and the treated fabric loses its flame resistance, the nanotech approach could still be used to protect textiles and durable goods that aren’t frequently washed, such as upholstery, mattress pads, box spring covers, automotive interiors, and firefighter coats.

This is one of the images that accompany the article,

Cross-section of a cotton fiber with clay nanoparticles attached. (from: http://www.ars.usda.gov/is/AR/archive/apr12/cotton0412.htm)

If you are interested in the work being done by the US Dept. of Agriculture’s Agricultural Research Service on cotton, there’s a lot more than I managed to excerpt.

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

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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, olli.ikkala@aalto.fi 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, runa0325@gmail.com 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, mmaclach@chem.ubc.ca 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, derek.gray@mcgill.ca 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, paul.gatenholm@chalmers.se 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.

Nanotechnology reaches its adolescence?

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They (American Association for the Advancement of Science [AAAS], the American Chemical Society [ACS], and the Georgetown University Program on Science in the Public Interest) will be hosting a discussion, Nanotechnology in the 2010s: The Teen Years, on Nov. 21, 2011 in Washington, DC.

This is part of a series, Science & Society: Global Challenges, hosted at the AAAS auditorium at 1200 New York Avenue. The reception starts at 5 pm EST, and the discussion begins at 6:00 pm and finishes at 7:30 pm. You do need to RSVP if you are attending at the AAAS  ‘Global Challenges’ webpage, which specifies, No powerpoint. No notes. Just candid conversations …

I did get a copy of the media release from the ACS, which you can view here in the Nov. 15, 2011 news item on Nanowerk.

From the media release, here’s a list of the expert discussants,

Experts:   Pedro Alvarez, Department of Civil and
Environmental Engineering, Rice  University

                    Omid Farokhzad, Brigham and Women’s
Hospital, Harvard Medical School

                    Debra Kaiser, Ceramics Division, National
Institute of Standards and Technology (NIST)

Host:         David Kestenbaum, NPR [National Public
Radio]

Here are the questions they will be discussing (from the ACS media release),

Since the 1990s, nanotechnology has been lauded as the key to transforming a wide array of innovative fields from biomedicine and electronics to energy, textiles and transportation, inspiring the National Nanotechnology Initiative (NNI) in 2000.

Now in the 2010s, is nanotechnology coming of age? Is the anticipated explosion of new products such as lighting, electronic displays, pharmaceuticals, solar photovoltaic cells and water treatment systems coming to fruition, or is NNI still in its research and development infancy? How should the United States allocate funds for research with such a strong potential to deliver economic innovations? These questions and others will be addressed Monday, Nov. 21, as part of the 2011 Science & Society: Global Challenges Discussion Series.

The ACS podcasts these discussions but you may have to wait a few weeks before viewing the nanotechnology discussion. The most recent available podcast of a Global Challenges discussion is the Oct. 3, 2011 discussion about Cyber Attack. The Oct. 24 discussion about Fukushima and the Nov. 7 discussion about Infectious Diseases have not been posted as of 11 am PST, Nov. 16, 2011.

Omid Farokhzad, one of the Global Challenges nanotechnology experts, was last mentioned on this blog in conjunction with a deal his companies (BIND and Selecta) made with RUSNANO (Russian Nanotechnologies Corporation) in my Oct. 28, 2011 posting. He was also featured in part 2 (More than Human, which is available for viewing online) of The Nano Revolution series broadcast, Oct. 20, 2011, by the Canadian Broadcasting Corporation as part of The Nature of Things programming. I did comment on the episode in my Oct. 26, 2011 posting but did not mention Farokhzad.