Tag Archives: ACS

A dog’s intimate understanding of chemical communication: sniffing butts

The American Chemical Society (ACS) has made available a video which answers a question almost everyone has asked at one time or another, why do dogs sniff each other’s bottoms?

Here’s how a July 28, 2014 ACS news release describes this line of inquiry,

Here at Reactions, we ask the tough questions to get to the bottom of the biggest scientific quandaries. In that spirit, this week’s video explains why dogs sniff each other’s butts. It’s a somewhat silly question with a surprisingly complex answer. This behavior is just one of many interesting forms of chemical communication in the animal kingdom

Without more ado, the video,

You can find more videos in ACS’s Reactions series here. (This series was formerly known as Bitesize Science.)

Earth Day, Water Day, and every day

I’m blaming my confusion on the American Chemical Society (ACS) which seemed to be celebrating Earth Day on April 15, 2014 as per its news release highlighting their “Chemists Celebrate Earth Day” video series  while in Vancouver, Canada, we’re celebrating it on April 26, 2014 and elsewhere it seems to be on April 20, this year. Regardless, here’s more about how chemist’s are celebrating from the ACS news release,

Water is arguably the most important resource on the planet. In celebration of Earth Day, the American Chemical Society (ACS) is showcasing three scientists whose research keeps water safe, clean and available for future generations. Geared toward elementary and middle school students, the “Chemists Celebrate Earth Day” series highlights the important work that chemists and chemical engineers do every day. The videos are available at http://bit.ly/CCED2014.

The series focuses on the following subjects:

  • Transforming Tech Toys- Featuring Aydogan Ozcan, Ph.D., of UCLA: Ozcan takes everyday gadgets and turns them into powerful mobile laboratories. He’s made a cell phone into a blood analyzer and a bacteria detector, and now he’s built a device that turns a cell phone into a water tester. It can detect very harmful mercury even at very low levels.
  • All About Droughts - Featuring Collins Balcombe of the U.S. Bureau of Reclamation: Balcombe’s job is to keep your drinking water safe and to find new ways to re-use the water that we flush away everyday so that it doesn’t go to waste, especially in areas that don’t get much rain.
  • Cleaning Up Our Water – Featuring Anne Morrissey, Ph.D., of Dublin City University: We all take medicines, but did you know that sometimes the medicine doesn’t stay in our bodies? It’s up to Anne Morrissey to figure out how to get potentially harmful pharmaceuticals out of the water supply, and she’s doing it using one of the most plentiful things on the planet: sunlight.

Sadly, I missed marking World Water Day which according to a March 21, 2014 news release I received was being celebrated on Saturday, March 22, 2014 with worldwide events and the release of a new UN report,

World Water Day: UN Stresses Water and Energy Issues 

Tokyo Leads Public Celebrations Around the World

Tokyo — March 21 — The deep-rooted relationships between water and energy were highlighted today during main global celebrations in Tokyo marking the United Nations’ annual World Water Day.

“Water and energy are among the world’s most pre-eminent challenges. This year’s focus of World Water Day brings these issues to the attention of the world,” said Michel Jarraud, Secretary-General of the World Meteorological Organization and Chair of UN-Water, which coordinates World Water Day and freshwater-related efforts UN system-wide.

The UN predicts that by 2030 the global population will need 35% more food, 40% more water and 50% more energy. Already today 768 million people lack access to improved water sources, 2.5 billion people have no improved sanitation and 1.3 billion people cannot access electricity.

“These issues need urgent attention – both now and in the post-2015 development discussions. The situation is unacceptable. It is often the same people who lack access to water and sanitation who also lack access to energy, ” said Mr. Jarraud.

The 2014 World Water Development Report (WWDR) – a UN-Water flagship report, produced and coordinated by the World Water Assessment Programme, which is hosted and led by UNESCO – is released on World Water Day as an authoritative status report on global freshwater resources. It highlights the need for policies and regulatory frameworks that recognize and integrate approaches to water and energy priorities.

WWDR, a triennial report from 2003 to 2012, this year becomes an annual edition, responding to the international community’s expression of interest in a concise, evidence-based and yearly publication with a specific thematic focus and recommendations.

WWDR 2014 underlines how water-related issues and choices impact energy and vice versa. For example: drought diminishes energy production, while lack of access to electricity limits irrigation possibilities.

The report notes that roughly 75% of all industrial water withdrawals are used for energy production. Tariffs also illustrate this interdependence: if water is subsidized to sell below cost (as is often the case), energy producers – major water consumers – are less likely to conserve it.  Energy subsidies, in turn, drive up water usage.

The report stresses the imperative of coordinating political governance and ensuring that water and energy prices reflect real costs and environmental impacts.

“Energy and water are at the top of the global development agenda,” said the Rector of United Nations University, David Malone, this year’s coordinator of World Water Day on behalf of UN-Water together with the United Nations Industrial Development Organization (UNIDO).

“Significant policy gaps exist in this nexus at present, and the UN plays an instrumental role in providing evidence and policy-relevant guidance. Through this day, we seek to inform decision-makers, stakeholders and practitioners about the interlinkages, potential synergies and trade-offs, and highlight the need for appropriate responses and regulatory frameworks that account for both water and energy priorities. From UNU’s perspective, it is essential that we stimulate more debate and interactive dialogue around possible solutions to our energy and water challenges.”

UNIDO Director-General LI Yong, emphasized the importance of water and energy for inclusive and sustainable industrial development.

“There is a strong call today for integrating the economic dimension, and the role of industry and manufacturing in particular, into the global post-2015 development priorities. Experience shows that environmentally sound interventions in manufacturing industries can be highly effective and can significantly reduce environmental degradation. I am convinced that inclusive and sustainable industrial development will be a key driver for the successful integration of the economic, social and environmental dimensions,” said Mr. LI.

Rather unusually, Michael Bergerrecently published two Nanowerk Spotlight articles about water (is there theme, anyone?) within 24 hours of each other. In his March 26, 2014 Spotlight article, Michael Berger focuses on graphene and water remediation (Note: Links have been removed),

The unique properties of nanomaterials are beneficial in applications to remove pollutants from the environment. The extremely small size of nanomaterial particles creates a large surface area in relation to their volume, which makes them highly reactive, compared to non-nano forms of the same materials.

The potential impact areas for nanotechnology in water applications are divided into three categories: treatment and remediation; sensing and detection: and pollution prevention (read more: “Nanotechnology and water treatment”).

Silver, iron, gold, titanium oxides and iron oxides are some of the commonly used nanoscale metals and metal oxides cited by the researchers that can be used in environmental remediation (read more: “Overview of nanomaterials for cleaning up the environment”).

A more recent entrant into this nanomaterial arsenal is graphene. Individual graphene sheets and their functionalized derivatives have been used to remove metal ions and organic pollutants from water. These graphene-based nanomaterials show quite high adsorption performance as adsorbents. However they also cause additional cost because the removal of these adsorbent materials after usage is difficult and there is the risk of secondary environmental pollution unless the nanomaterials are collected completely after usage.

One solution to this problem would be the assembly of individual sheets into three-dimensional (3D) macroscopic structures which would preserve the unique properties of individual graphene sheets, and offer easy collecting and recycling after water remediation.

The March 27, 2014 Nanowerk Spotlight article was written by someone at Alberta’s (Canada) Ingenuity Lab and focuses on their ‘nanobiological’ approach to water remediation (Note: Links have been removed),

At Ingenuity Lab in Edmonton, Alberta, Dr. Carlo Montemagno and a team of world-class researchers have been investigating plausible solutions to existing water purification challenges. They are building on Dr. Montemagno’s earlier patented discoveries by using a naturally-existing water channel protein as the functional unit in water purification membranes [4].

Aquaporins are water-transport proteins that play an important osmoregulation role in living organisms [5]. These proteins boast exceptionally high water permeability (~ 1010 water molecules/s), high selectivity for pure water molecules, and a low energy cost, which make aquaporin-embedded membrane well suited as an alternative to conventional RO membranes.

Unlike synthetic polymeric membranes, which are driven by the high pressure-induced diffusion of water through size selective pores, this technology utilizes the biological osmosis mechanism to control the flow of water in cellular systems at low energy. In nature, the direction of osmotic water flow is determined by the osmotic pressure difference between compartments, i.e. water flows toward higher osmotic pressure compartment (salty solution or contaminated water). This direction can however be reversed by applying a pressure to the salty solution (i.e., RO).

The principle of RO is based on the semipermeable characteristics of the separating membrane, which allows the transport of only water molecules depending on the direction of osmotic gradient. Therefore, as envisioned in the recent publication (“Recent Progress in Advanced Nanobiological Materials for Energy and Environmental Applications”), the core of Ingenuity Lab’s approach is to control the direction of water flow through aquaporin channels with a minimum level of pressure and to use aquaporin-embedded biomimetic membranes as an alternative to conventional RO membranes.

Here’s a link to and a citation for Montemagno’s and his colleague’s paper,

Recent Progress in Advanced Nanobiological Materials for Energy and Environmental Applications by Hyo-Jick Choi and Carlo D. Montemagno. Materials 2013, 6(12), 5821-5856; doi:10.3390/ma6125821

This paper is open access.

Returning to where I started, here’s a water video featuring graphene from the ACS celebration of Earth Day 2014,

Happy Earth Day!

Chemists wish us all a Happy April Fool’s Day with puns!

The American Chemical Society (ACS) has produced a video of chemistry jokes/puns,

From the March 31, 2014 ACS news release on EurekAlert,

… the American Chemical Society’s (ACS) Reactions video series is celebrating with an episode featuring our favorite chemistry jokes. Which two elements look cute together? Why is father water concerned about his “iced out” son? What do you get when you combine sulfur, tungsten and silver? Get all the punchlines in the latest Reactions episode, available at: http://youtu.be/C5RZRkhk0OM.

Subscribe to the series at Reactions YouTube, and follow us on Twitter @ACSreactions.

Happy April Fool’s Day1

 

GUMBOS, the nanoparticle kind

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?

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.

‘Nano fest’ at the 245th meeting of the American Chemical Society

The American Chemical Society’s (ACS) 245th meeting (April 7 – 11, 2013) features a few items about nanotechnology: the funding of it and the toxicological testing of it, in two separate news items which bear a ‘political’ link.

An April 9, 2013 news item on Azonano tells of concerns regarding recent funding cuts resulting from the US budget sequestration,

Speaking at the 245th National Meeting & Exposition of the American Chemical Society, the world’s largest scientific society, A. Paul Alivisatos, Ph.D., expressed concern that the cuts come when nanotechnology is poised to deliver on those promises. He told the meeting, which continues through Thursday, that ill-conceived cuts could set back America’s progress in nanotechnology by decades.

“The National Science Foundation announced that they will issue a thousand fewer new grants this year because of sequestration,” said Alivisatos, referring to the across-the-board mandatory federal budget cuts that took effect on March 1. “What it means in practice is that an entire generation of early career scientists, some of our brightest and most promising scientists, will not have the funding to launch their careers and begin research properly, in the pathway that has established the United States as leader in nanotechnology research. It will be a setback, perhaps quite serious, for our international competitiveness in this key field.”

Alivisatos described applications of nanotechnology that can help reduce fossil fuel consumption and the accompanying emissions of carbon dioxide, the main greenhouse gas. He is professor of chemistry and materials science and the Larry and Diane Bock Professor of Nanotechnology at the University of California at Berkeley, director of the Lawrence Berkeley National Laboratory and co-editor of the ACS journal Nano Letters. …

Alivisatos expressed concern, however, that cuts in federal funding will take a heavy toll on the still-emerging field. He explained that the reductions stand to affect scientists at almost every stage of making contributions to society. Young scientists, for instance, will find it more difficult to launch research programs in new and promising fields.[emphases mine]  Established scientists will have to trim research programs, and may not have the money to explore promising new leads.

“We haven’t been able to communicate adequately with the public and policymakers, and explain the impact of what may sound like small and unimportant cuts in funding.” Alivisatos said. “A 5 percent reduction in funding — well, to the public, it seems like nothing. In reality, these cuts will be applied in ways that do maximal damage to our ability to be globally competitive in the future.”

Coincidentally or not,  the ACS had placed an Apr. 8, 2013 news release on EurekAlert highlighting some work in the field of nanotoxicology led by a ‘young’ scientist (I imagine she received her funding prior to sequestration) doing some exciting work,

Earlier efforts to determine the health and environmental effects of the nanoparticles that are finding use in hundreds of consumer products may have produced misleading results by embracing traditional toxicology tests that do not take into account the unique properties of bits of material so small that 100,000 could fit in the period at the end of this sentence.

That was among the observations presented here today at the 245th National Meeting & Exposition of the American Chemical Society (ACS), the world’s largest scientific society, by one of the emerging leaders in nanoscience research. The talk by Christy Haynes, Ph.D., was among almost 12,000 presentations at the gathering, which organizers expect to attract more than 14,000 scientists and others.

Haynes delivered the inaugural Kavli Foundation Emerging Leader in Chemistry Lecture at the meeting, … Sponsored by the Kavli Foundation, the Emerging Leaders Lectures recognize the work of outstanding young chemical scientists. [emphasis mine] …

“Christy Haynes is the perfect scientist to launch this prestigious lecture series,” said Marinda Li Wu, Ph.D., president of the ACS. “Haynes’ research is making an impact in the scientific community in efforts to use nanoparticles and nanotechnology in medicine and other fields. And that research has sparked the popular imagination, as well. Haynes was included in Popular Science‘s ‘Brilliant 10′ list, a group of ‘geniuses shaking up science today.’ [emphasis mine] We are delighted to collaborate with the Kavli Foundation in highlighting the contributions of such individuals.”

Moving on from politics to science, the EurekAlert Apr. 8, 2013 news release offers a standard discussion regarding gold and nanoparticle gold before highlighting the aspect that marks Haynes’ fresh approach to toxicity at the nanoscale,

A 1-ounce nugget of pure gold, for instance, has the same chemical and physical properties as a 2-ounce nugget or a 27-pound gold bar. For nanoparticles, however, size often dictates the physical and chemical properties, and those properties change as the size decreases.

Haynes said that some of the earlier nanotoxicology tests did not fully take those and other factors into account when evaluating the effects of nanoparticles. In some cases, for instance, the bottom line in those tests was whether cells growing in laboratory cultures lived or died after exposure to a nanoparticle.

“While these results can be useful, there are two important limitations,” Haynes explained. “A cell can be alive but unable to function properly, and it would not be apparent in those tests. In addition, the nature of nanoparticles — they’re more highly reactive — can cause ‘false positives’ in these assays.”

Haynes described a new approach used in her team’s work in evaluating the toxicity of nanoparticles. It focuses on monitoring how exposure to nanoparticles affects a cell’s ability to function normally, rather than just its ability to survive the exposure. In addition, they have implemented measures to reduce “false-positive” test results, which overestimate nanoparticle toxicity. One of the team’s safety tests, for instance, determines whether key cells in the immune system can still work normally after exposure to nanoparticles. In another, the scientists determine whether bacteria exposed to nanoparticles can still communicate with each other, engaging in the critical biochemical chatter that enables bacteria to form biofilms, communities essential for them to multiply in ways that lead to infections.

“So far, we have found that nanoparticles made of silver or titanium may be the most problematic, though I would say that neither is as bad as some of the alarmist media speculations, especially when they are stabilized appropriately,” said Haynes. “I think that it will be possible to create safe, stable coatings on nanoparticles that will make them stable and allow them to leave the body appropriately. We need more research, of course, in order to make informed decisions.”

Hopefully, you find this mixture of science and politics as interesting as I do.

ETA Apr. 10, 2013: Dexter Johnson has commented on and provided some contextual information about nanotechnology research funding in the US in response to the Alivisatos talk about sequestration and its possible impact on nanotechnology research in Apr. 9, 2013 posting (Note: A link has been removed),

There is always room for the argument that reassessing and reallocating resources can help make nanotechnology more efficient and productive, something observers have pointed out in NASA taking on less of its own nanotechnology research and outsourcing it to other government organizations. But it’s not always easy to tell which fundamental research projects will turn out to have been the most productive, and worse, the timing of these cuts could be extremely painful as they occur at a critical moment for U.S. nanotechnology.

Dexter’s piece is well worth reading.

Algae factories could produce nanocellulose for biofuels and more

The American Chemical Society (ACS) is holding its 245th meeting April 7 – 11, 2013 and its first International Symposium on Bacterial Nanocellulose simultaneously. I have written about nanocellulose previously but it’s always been concerned with the type derived from plant matter; bacterial nanocellulose is new to me but not the scientific community as the Apr. 8, 2013 news item on Azonano notes,

In the 1800s, French scientist Louis Pasteur first discovered that vinegar-making [and Kombucha tea and nata de coco] bacteria make “a sort of moist skin, swollen, gelatinous and slippery” — a “skin” now known as bacterial nanocellulose. Nanocellulose made by bacteria has advantages, including ease of production and high purity that fostered the kind of scientific excitement reflected in the first international symposium on the topic, Brown [R. Malcolm Brown, Jr., Ph.D.] pointed out.

Before going on to this latest research, here’s a description of cellulose and nanocellulose as per its presence in plant material (from the news item),

Cellulose is the most abundant organic polymer on Earth, a material, like plastics, consisting of molecules linked together into long chains. Cellulose makes up tree trunks and branches, corn stalks and cotton fibers, and it is the main component of paper and cardboard. People eat cellulose in “dietary fiber,” the indigestible material in fruits and vegetables. Cows, horses and termites can digest the cellulose in grass, hay and wood.

Most cellulose consists of wood fibers and cell wall remains. Very few living organisms can actually synthesize and secrete cellulose in its native nanostructure form of microfibrils. At this level, nanometer-scale fibrils are very hydrophilic and look like jelly. A nanometer is one-millionth the thickness of a U.S. dime. Nevertheless, cellulose shares the unique properties of other nanometer-sized materials — properties much different from large quantities of the same material. Nanocellulose-based materials can be stronger than steel and stiffer than Kevlar. Great strength, light weight and other advantages has fostered interest in using it in everything from lightweight armor and ballistic glass to wound dressings and scaffolds for growing replacement organs for transplantation.

A new kind of bacteria actively entered the nanocellulose picture in 2001 (from the news item) allowing Brown to exploit research he had been pursuing since the 1970s (from the news item),

Brown recalled that in 2001, a discovery by David Nobles, Ph.D., a member of the research team at the University of Texas at Austin, refocused their research on nanocellulose, but with a different microbe. Nobles established that several kinds of blue-green algae, which are mainly photosynthetic bacteria much like the vinegar-making bacteria in basic structure; however, these blue-green algae, or cyanobacteria, as they are called, can produce nanocellulose. One of the largest problems with cyanobacterial nanocellulose is that it is not made in abundant amounts in nature. If it could be scaled up, Brown describes this as “one of the most important discoveries in plant biology.”

While I find the science interesting, it’s Brown’s comments about the policy and politics of commercializing nanocellulose-based fuels that intrigue me (from the news item),

In his report at the ACS meeting, Brown described how his team already has genetically engineered the cyanobacteria to produce one form of nanocellulose, the long-chain, or polymer, form of the material. And they are moving ahead with the next step, engineering the cyanobacteria to synthesize a more complete form of nanocellulose, one that is a polymer with a crystalline architecture. He also said that operations are being scaled up, with research moving from laboratory-sized tests to larger outdoor facilities.

Brown expressly pointed out that one of the major barriers to commercializing nanocellulose fuels involves national policy and politics, rather than science. Biofuels, he said, will face a difficult time for decades into the future in competing with the less-expensive natural gas now available with hydraulic fracturing, or “fracking.”  [emphasis mine] In the long run, the United States will need sustainable biofuels, he said, citing the importance of national energy policies that foster parallel development and commercialization of biofuels.

Gold nanoparticles can make your hair brown

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.