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Nanoparticles in baby formula

Needle-like particles of hydroxyapatite found in infant formula by ASU researchers. Westerhoff and Schoepf/ASU, CC BY-ND

Needle-like particles of hydroxyapatite found in infant formula by ASU [Arizona State University] researchers. Westerhoff and Schoepf/ASU, CC BY-ND

Nanowerk is featuring an essay about hydroxyapatite nanoparticles in baby formula written by Dr. Andrew Maynard in a May 17, 2016 news item (Note: A link has been removed),

There’s a lot of stuff you’d expect to find in baby formula: proteins, carbs, vitamins, essential minerals. But parents probably wouldn’t anticipate finding extremely small, needle-like particles. Yet this is exactly what a team of scientists here at Arizona State University [ASU] recently discovered.

The research, commissioned and published by Friends of the Earth (FoE) – an environmental advocacy group – analyzed six commonly available off-the-shelf baby formulas (liquid and powder) and found nanometer-scale needle-like particles in three of them. The particles were made of hydroxyapatite – a poorly soluble calcium-rich mineral. Manufacturers use it to regulate acidity in some foods, and it’s also available as a dietary supplement.

Andrew’s May 17, 2016 essay first appeared on The Conversation website,

Looking at these particles at super-high magnification, it’s hard not to feel a little anxious about feeding them to a baby. They appear sharp and dangerous – not the sort of thing that has any place around infants. …

… questions like “should infants be ingesting them?” make a lot of sense. However, as is so often the case, the answers are not quite so straightforward.

Andrew begins by explaining about calcium and hydroxyapatite (from The Conversation),

Calcium is an essential part of a growing infant’s diet, and is a legally required component in formula. But not necessarily in the form of hydroxyapatite nanoparticles.

Hydroxyapatite is a tough, durable mineral. It’s naturally made in our bodies as an essential part of bones and teeth – it’s what makes them so strong. So it’s tempting to assume the substance is safe to eat. But just because our bones and teeth are made of the mineral doesn’t automatically make it safe to ingest outright.

The issue here is what the hydroxyapatite in formula might do before it’s digested, dissolved and reconstituted inside babies’ bodies. The size and shape of the particles ingested has a lot to do with how they behave within a living system.

He then discusses size and shape, which are important at the nanoscale,

Size and shape can make a difference between safe and unsafe when it comes to particles in our food. Small particles aren’t necessarily bad. But they can potentially get to parts of our body that larger ones can’t reach. Think through the gut wall, into the bloodstream, and into organs and cells. Ingested nanoscale particles may be able to interfere with cells – even beneficial gut microbes – in ways that larger particles don’t.

These possibilities don’t necessarily make nanoparticles harmful. Our bodies are pretty well adapted to handling naturally occurring nanoscale particles – you probably ate some last time you had burnt toast (carbon nanoparticles), or poorly washed vegetables (clay nanoparticles from the soil). And of course, how much of a material we’re exposed to is at least as important as how potentially hazardous it is.

Yet there’s a lot we still don’t know about the safety of intentionally engineered nanoparticles in food. Toxicologists have started paying close attention to such particles, just in case their tiny size makes them more harmful than otherwise expected.

Currently, hydroxyapatite is considered safe at the macroscale by the US Food and Drug Administration (FDA). However, the agency has indicated that nanoscale versions of safe materials such as hydroxyapatite may not be safe food additives. From Andrew’s May 17, 2016 essay,

Hydroxyapatite is a tough, durable mineral. It’s naturally made in our bodies as an essential part of bones and teeth – it’s what makes them so strong. So it’s tempting to assume the substance is safe to eat. But just because our bones and teeth are made of the mineral doesn’t automatically make it safe to ingest outright.

The issue here is what the hydroxyapatite in formula might do before it’s digested, dissolved and reconstituted inside babies’ bodies. The size and shape of the particles ingested has a lot to do with how they behave within a living system. Size and shape can make a difference between safe and unsafe when it comes to particles in our food. Small particles aren’t necessarily bad. But they can potentially get to parts of our body that larger ones can’t reach. Think through the gut wall, into the bloodstream, and into organs and cells. Ingested nanoscale particles may be able to interfere with cells – even beneficial gut microbes – in ways that larger particles don’t.These possibilities don’t necessarily make nanoparticles harmful. Our bodies are pretty well adapted to handling naturally occurring nanoscale particles – you probably ate some last time you had burnt toast (carbon nanoparticles), or poorly washed vegetables (clay nanoparticles from the soil). And of course, how much of a material we’re exposed to is at least as important as how potentially hazardous it is.Yet there’s a lot we still don’t know about the safety of intentionally engineered nanoparticles in food. Toxicologists have started paying close attention to such particles, just in case their tiny size makes them more harmful than otherwise expected.

Putting particle size to one side for a moment, hydroxyapatite is classified by the US Food and Drug Administration (FDA) as “Generally Regarded As Safe.” That means it considers the material safe for use in food products – at least in a non-nano form. However, the agency has raised concerns that nanoscale versions of food ingredients may not be as safe as their larger counterparts.Some manufacturers may be interested in the potential benefits of “nanosizing” – such as increasing the uptake of vitamins and minerals, or altering the physical, textural and sensory properties of foods. But because decreasing particle size may also affect product safety, the FDA indicates that intentionally nanosizing already regulated food ingredients could require regulatory reevaluation.In other words, even though non-nanoscale hydroxyapatite is “Generally Regarded As Safe,” according to the FDA, the safety of any nanoscale form of the substance would need to be reevaluated before being added to food products.Despite this size-safety relationship, the FDA confirmed to me that the agency is unaware of any food substance intentionally engineered at the nanoscale that has enough generally available safety data to determine it should be “Generally Regarded As Safe.”Casting further uncertainty on the use of nanoscale hydroxyapatite in food, a 2015 report from the European Scientific Committee on Consumer Safety (SCCS) suggests there may be some cause for concern when it comes to this particular nanomaterial.Prompted by the use of nanoscale hydroxyapatite in dental products to strengthen teeth (which they consider “cosmetic products”), the SCCS reviewed published research on the material’s potential to cause harm. Their conclusion?

The available information indicates that nano-hydroxyapatite in needle-shaped form is of concern in relation to potential toxicity. Therefore, needle-shaped nano-hydroxyapatite should not be used in cosmetic products.

This recommendation was based on a handful of studies, none of which involved exposing people to the substance. Researchers injected hydroxyapatite needles directly into the bloodstream of rats. Others exposed cells outside the body to the material and observed the effects. In each case, there were tantalizing hints that the small particles interfered in some way with normal biological functions. But the results were insufficient to indicate whether the effects were meaningful in people.

As Andrew also notes in his essay, none of the studies examined by the SCCS OEuropean Scientific Committee on Consumer Safety) looked at what happens to nano-hydroxyapatite once it enters your gut and that is what the researchers at Arizona State University were considering (from the May 17, 2016 essay),

The good news is that, according to preliminary studies from ASU researchers, hydroxyapatite needles don’t last long in the digestive system.

This research is still being reviewed for publication. But early indications are that as soon as the needle-like nanoparticles hit the highly acidic fluid in the stomach, they begin to dissolve. So fast in fact, that by the time they leave the stomach – an exceedingly hostile environment – they are no longer the nanoparticles they started out as.

These findings make sense since we know hydroxyapatite dissolves in acids, and small particles typically dissolve faster than larger ones. So maybe nanoscale hydroxyapatite needles in food are safer than they sound.

This doesn’t mean that the nano-needles are completely off the hook, as some of them may get past the stomach intact and reach more vulnerable parts of the gut. But the findings do suggest these ultra-small needle-like particles could be an effective source of dietary calcium – possibly more so than larger or less needle-like particles that may not dissolve as quickly.

Intriguingly, recent research has indicated that calcium phosphate nanoparticles form naturally in our stomachs and go on to be an important part of our immune system. It’s possible that rapidly dissolving hydroxyapatite nano-needles are actually a boon, providing raw material for these natural and essential nanoparticles.

While it’s comforting to know that preliminary research suggests that the hydroxyapatite nanoparticles are likely safe for use in food products, Andrew points out that more needs to be done to insure safety (from the May 17, 2016 essay),

And yet, even if these needle-like hydroxyapatite nanoparticles in infant formula are ultimately a good thing, the FoE report raises a number of unresolved questions. Did the manufacturers knowingly add the nanoparticles to their products? How are they and the FDA ensuring the products’ safety? Do consumers have a right to know when they’re feeding their babies nanoparticles?

Whether the manufacturers knowingly added these particles to their formula is not clear. At this point, it’s not even clear why they might have been added, as hydroxyapatite does not appear to be a substantial source of calcium in most formula. …

And regardless of the benefits and risks of nanoparticles in infant formula, parents have a right to know what’s in the products they’re feeding their children. In Europe, food ingredients must be legally labeled if they are nanoscale. In the U.S., there is no such requirement, leaving American parents to feel somewhat left in the dark by producers, the FDA and policy makers.

As far as I’m aware, the Canadian situation is much the same as the US. If the material is considered safe at the macroscale, there is no requirement to indicate that a nanoscale version of the material is in the product.

I encourage you to read Andrew’s essay in its entirety. As for the FoE report (Nanoparticles in baby formula: Tiny new ingredients are a big concern), that is here.

AquAdvantage salmon (genetically modified) approved for consumption in Canada

This is an update of the AquAdvantage salmon story covered in my Dec. 4, 2015 post (scroll down about 40% of the way). At the time, the US Food and Drug Administration (FDA) had just given approval for consumption of the fish. There was speculation there would be a long hard fight over approval in Canada. This does not seem to have been the case, according to a May 10, 2016 news item announcing Health Canada’s on phys.org,

Canada’s health ministry on Thursday [May 19, 2016] approved a type of genetically modified salmon as safe to eat, making it the first transgenic animal destined for Canadian dinner tables.

This comes six months after US authorities gave the green light to sell the fish in American grocery stores.

The decisions by Health Canada and the US Food and Drug Administration follow two decades of controversy over the fish, which is an Atlantic salmon injected with genes from Pacific Chinook salmon and a fish known as the ocean pout to make it grow faster.

The resulting fish, called AquAdvantage Salmon, is made by AquaBounty Technologies in Massachusetts, and can reach adult size in 16 to 18 months instead of 30 months for normal Atlantic salmon.

A May 19, 2016 BIOTECanada news release on businesswire provides more detail about one of the salmon’s Canadian connections,

Canadian technology emanating from Memorial University developed the AquAdvantage salmon by introducing a growth hormone gene from Chinook salmon into the genome of Atlantic salmon. This results in a salmon which grows faster and reaches market size quicker and AquAdvantage salmon is identical to other farmed salmon. The AquAdvantage salmon also received US FDA approval in November 2015. With the growing world population, AquaBounty is one of many biotechnology companies offering safe and sustainable means to enhance the security and supply of food in the world. AquaBounty has improved the productivity of aquaculture through its use of biotechnology and modern breeding technics that have led to the development of AquAdvantage salmon.

“Importantly, today’s approval is a result of a four year science-based regulatory approval process which involved four federal government departments including Agriculture and AgriFood, Canada Food Inspection Agency, Environment and Climate Change, Fisheries and Oceans and Health which demonstrates the rigour and scope of science based regulatory approvals in Canada. Coupled with the report from the [US] National Academy of Sciences today’s [May 19, 2016] approval clearly demonstrates that genetic engineering of food is not only necessary but also extremely safe,” concluded Casey [Andrew Casey, President and CEO BIOTECanada].

There’s another connection, the salmon hatcheries are based in Prince Edward Island.

While BIOTECanada’s Andrew Casey is crowing about this approval, it should be noted that there was a losing court battle with British Columbia’s Living Oceans Society and Nova Scotia’s Ecology Action Centre both challenging the federal government’s approval. They may have lost battle but, as the cliché goes, ‘the war is not over yet’. There’s an Issue about the lack of labeling and there’s always the  possibility that retailers and/or consumers may decide to boycott the fish.

As for BIOTECanada, there’s this description from the news release,

BIOTECanada is the national industry association with more than 230 members reflecting the diverse nature of Canada’s health, industrial and agricultural biotechnology sectors. In addition to providing significant health benefits for Canadians, the biotechnology industry has quickly become an essential part of the transformation of many traditional cornerstones of the Canadian economy including manufacturing, automotive, energy, aerospace and forestry industries. Biotechnology in all of its applications from health, agriculture and industrial is offering solutions for the collective population.

You can find the BIOTECanada website here.

Personally, I’m a bit ambivalent about it all. I understand the necessity for changing our food production processes but I do think more attention should be paid to consumers’ concerns and that organizations such as BIOTECanada could do a better job of communicating.

Chief science adviser/advisor for Canada (we’re still waiting)

I half-thought we might get an announcement about Canada’s new science adviser/advisor/officer during the 2016 Science Odyssey  (formerly Canada’s National Science and Technology Week) being held from May 6–15, 2016. Especially in light of Science Minister Kirsty Duncan’s May 6, 2016 article “Duncan: New federal science adviser will be key to evidence-based policy” for the Ottawa Citizen,

The creation of a permanent Chief Science Officer demonstrates our government’s commitment to making sure science finds its rightful place at the federal table. In the six months since arriving in office, I have consulted extensively – both domestically and internationally – on this position. I have examined how similar positions, often called a chief science adviser, work in other countries such as the United Kingdom, New Zealand, the United States and Israel. My survey of international models will help create a position that is modern and yet tailor-made to suit Canada.

To-date, I have received valuable input from more than 80 experts, stakeholders and parliamentary colleagues from across the political spectrum. They have provided views such as the importance of recruiting someone who can provide independent, transparent and non-partisan scientific advice to the prime minister and our government. Our consultations have also underscored the importance of building relationships between a Chief Science Officer and the research community that allow for the best scientific expertise to be part of decision-making at the highest levels of government.

Our stakeholders also emphasized the importance of appointing someone who would have access to and an open dialogue with federal scientists, along with other scientists across Canada and abroad.

And when I speak of scientists here, I mean all scientists. As Stephen J. Toope, president of the Federation for the Humanities and Social Sciences, wrote in the Citizen Friday [May 6, 2016], our lead scientist would be welcome to gather the best evidence from all scientific disciplines: the natural and applied sciences, engineering, health sciences and the social sciences and humanities. The officer would do so without the influence of political agendas. And with ease in both official languages.

I have learned from my consultations that in order for Canada to enhance its science advisory system and give this new position permanence, it is important to properly define and take the time necessary to recruit someone who has a deep respect for Canada’s scientists and the role of science in society. So far, I am encouraged that members of our stakeholder community and parliamentarians understand the need for a credible process to appoint a worthy individual who will serve our prime minister, our government, our citizens and scientists.

Tim Lougheed in a Feb. 29, 2016 article for the Canadian Science Policy Centre passed on a few thoughts from Sir Peter Gluckman, Chief Science Advisor (CSO; either advisor or adviser seems to be correct) to New Zealand’s Prime Minister,

So, the Canadian science adviser is supposed to have an impact on policy,

“There can be expectations that when you’re fighting for a science advisor you’re fighting for an in-house lobbyist for the science community,” he cautions. “But of course you’re not: you’re fighting for an in-house lobbyist for the use of science by government. There’s a really important difference.”

Gluckman was honoured this February [2016] in Washington [DC] at the annual meeting of the American Association for the Advancement of Science, which gave him its 2015 Award for Science Diplomacy. He understands the need for diplomacy in any kind of CSO undertaking, especially whenever he has found himself wedged in between a political leadership seeking objective consultation and a research community disappointed with their share of government funding.

“When the roles of science advisors get conflated, they tend to get more politicized,” he explains. “What we try to do is to show that science can be an apolitical powerful input into better decision-making by governments.”

Canada [has] already long taken advantage of this powerful input through the Science Technology and Innovation Council, created in 2007, and before that the Council of Science and Technology Advisors, which dates back to 1996. However, the deliberations of these bodies largely took place behind closed doors and neither was ever intended to maintain the public accountability and profile of a CSO, who could easily become a lightning rod in exceptional circumstances such as those that highlighted Koop’s career.

“They’re going to have to earn the trust of the Prime Minister and the Cabinet,” says University of Ottawa Biology Professor Rees Kassen. “They have to show value and at the same time they have to show value to the country.”

Kassen, a longtime advocate of bridge-building between government and the research community, underscores that “country” refers to everyone, not just those two parties. In order to succeed, the CSO must be seen to benefit Canada as a whole.

“I would like to see the role of science advisor not rely solely on the heroic capabilities of one person,” he adds. “We have a very rich ecosystem of scientific knowledge creation, of scientific activity, of scientific translation — and potentially, of scientific advice.”

Kassen, a longtime advocate of bridge-building between government and the research community, underscores that “country” refers to everyone, not just those two parties. In order to succeed, the CSO must be seen to benefit Canada as a whole.

“I would like to see the role of science advisor not rely solely on the heroic capabilities of one person,” he adds. “We have a very rich ecosystem of scientific knowledge creation, of scientific activity, of scientific translation — and potentially, of scientific advice.”

Gluckman — who himself coordinates the work of a variety of other science advisors located in other parts of the New Zealand government, and collaborates closely with the Royal Society of New Zealand (the National Academy)— absolutely agrees. Moreover, he concludes that the effectiveness of any CSO will depend on how far and wide their influence extends.

“That really determines how this role works,” he says. “Ultimately if this person doesn’t report across the whole of government, they can’t do the role I’m talking about.”

Of course, there are some assumptions being made as Paul Cairney *notes* in his March 10, 2016 article for the Guardian about science advice and its impact on policy and policymakers,

… these efforts will fail if scientists and other experts fail to understand how the policy process works. To do so requires us to reject two romantic notions: first, that policymakers will ever think like scientists; and second, that there is a clearly identifiable point of decision at which scientists can contribute evidence to make a demonstrable impact.

To better understand how policymakers think, we need a full account of “bounded rationality.” This phrase describes the fact that policymakers can only gather limited information before they make decisions quickly. They will have made a choice before you have a chance to say “more research is needed”! To do so, they use two short cuts: rational ways to gather quickly the best evidence on solutions to meet their goals; and irrational ways – including drawing on emotions and gut feeling – to identify problems even more quickly.

This highlights a potential flaw in academic strategies. The most common response to bounded rationality in scientific articles is to focus on the supply of evidence: to develop a hierarchy of evidence, which often privileges randomised control trials; to generate knowledge; and to present it in a form that is understandable to policymakers.

We need to pay more attention to the demand for evidence, taking more account of lurches of policymaker attention, often driven by quick and emotional decisions. For example, there is no point in taking the time to make evidence-based solutions easier to understand if policymakers are no longer interested. Successful advocates recognise the value of emotional appeals and simple stories to draw attention to a problem.

To identify when and how to contribute evidence, we need to understand the complicated environment in which policymaking takes place. There is no “policy cycle” in which to inject scientific evidence at the point of decision. Rather, the policy process is messy and often unpredictable. It is a complex system in which the same injection of evidence can have no effect, or a major effect.

The article offers more insight into the issues with science advice, evidence, and policymaking. Coincidentally Cairney was promoting a new book at the time (from Cairney’s article),

… his new book The Politics of Evidence Based Policymaking, which was launched this week by the Alliance for Useful Evidence. More details are available on his website.

All this speculation has been quite interesting and I look forward to an announcement at some point. For those who’d like more opinions about the matter, there’s the Canadian Science Policy Centre’s Chief Science Officer: Insights and Recommendations webpage, which, as of May 19, 2016, hosts seven opinion pieces including one from Ted Hsu, former Liberal Member of Parliament, one of the few to hold a science degree (in his case, physics).

*’notes’ added on May 19,2016 at 1412 PDT.

Frankenstein and Switzerland in 2016

The Frankenstein Bicentennial celebration is in process as various events and projects are now being launched. In a Nov. 12, 2015 posting I made mention of the Frankenstein Bicentennial Project 1818-2018 at Arizona State University (ASU; scroll down about 15% of the way),

… the Transmedia Museum (Frankenstein Bicentennial Project 1818-2018).  This project is being hosted by Arizona State University. From the project homepage,

No work of literature has done more to shape the way people imagine science and its moral consequences than Frankenstein; or The Modern Prometheus, Mary Shelley’s enduring tale of creation and responsibility. The novel’s themes and tropes—such as the complex dynamic between creator and creation—continue to resonate with contemporary audiences. Frankenstein continues to influence the way we confront emerging technologies, conceptualize the process of scientific research, imagine the motivations and ethical struggles of scientists, and weigh the benefits of innovation with its unforeseen pitfalls.

The Frankenstein Bicentennial Project will infuse science and engineering endeavors with considerations of ethics. It will use the power of storytelling and art to shape processes of innovation and empower public appraisal of techno-scientific research and creation. It will offer humanists and artists a new set of concerns around research, public policy, and the ramifications of exploration and invention. And it will inspire new scientific and technological advances inspired by Shelley’s exploration of our inspiring and terrifying ability to bring new life into the world. Frankenstein represents a landmark fusion of science, ethics, and literary expression.

The bicentennial provides an opportunity for vivid reflection on how science is culturally framed and understood by the public, as well as our ethical limitations and responsibility for nurturing the products of our creativity. It is also a moment to unveil new scientific and technological marvels, especially in the areas of synthetic biology and artificial intelligence. Engaging with Frankenstein allows scholars and educators, artists and writers, and the public at large to consider the history of scientific invention, reflect on contemporary research, and question the future of our technological society. Acting as a network hub for the bicentennial celebration, ASU will encourage and coordinate collaboration across institutions and among diverse groups worldwide.

2016 Frankenstein events

Now, there’s an exhibition in Switzerland where Frankenstein was ‘born’ according to a May 12, 2016 news item on phys.org,

Frankenstein, the story of a scientist who brings to life a cadaver and causes his own downfall, has for two centuries given voice to anxiety surrounding the unrelenting advance of science.

To mark the 200 years since England’s Mary Shelley first imagined the ultimate horror story during a visit to a frigid, rain-drenched Switzerland, an exhibit opens in Geneva Friday called “Frankenstein, Creation of Darkness”.

In the dimly-lit, expansive basement at the Martin Bodmer Foundation, a long row of glass cases holds 15 hand-written, yellowed pages from a notebook where Shelley in 1816 wrote the first version of what is considered a masterpiece of romantic literature.

The idea for her “miserable monster” came when at just 18 she and her future husband, English poet Percy Bysshe Shelley, went to a summer home—the Villa Diodati—rented by literary great Lord Byron on the outskirts of Geneva.

The current private owners of the picturesque manor overlooking Lake Geneva will also open their lush gardens to guided tours during the nearby exhibit which runs to October 9 [May 13 – Oct. 9, 2016].

While the spot today is lovely, with pink and purple lilacs spilling from the terraces and gravel walkways winding through rose-covered arches, in the summer of 1816 the atmosphere was more somber.

A massive eruption from the Tambora volcano in Indonesia wreaked havoc with the global climate that year, and a weather report for Geneva in June on display at the exhibit mentions “not a single leaf” had yet appeared on the oak trees.

To pass the time, poet Lord Byron challenged the band of literary bohemians gathered at the villa to each invent a ghost story, resulting in several famous pieces of writing.

English doctor and author John Polidori came up with the idea for “The Vampyre”, which was published three years later and is considered to have pioneered the romantic vampyre genre, including works like Bram Stoker’s “Dracula”.

That book figures among a multitude of first editions at the Geneva exhibit, including three of Mary Shelley’s “Frankenstein, or the Modern Prometheus”—the most famous story to emerge from the competition.

Here’s a description of the exhibit, from the Martin Bodmer Foundation’s Frankenstein webpage,

To celebrate the 200th anniversary of the writing of this historically influential work of literature, the Martin Bodmer Foundation presents a major exhibition on the origins of Frankenstein, the perspectives it opens and the questions it raises.

A best seller since its first publication in 1818, Mary Shelley’s novel continues to demand attention. The questions it raises remain at the heart of literary and philosophical concerns: the ethics of science, climate change, the technologisation of the human body, the unconscious, human otherness, the plight of the homeless and the dispossessed.

The exposition Frankenstein: Creation of Darkness recreates the beginnings of the novel in its first manuscript and printed forms, along with paintings and engravings that evoke the world of 1816. A variety of literary and scientific works are presented as sources of the novel’s ideas. While exploring the novel’s origins, the exhibition also evokes the social and scientific themes of the novel that remain important in our own day.

For what it’s worth, I have come across analyses which suggest science and technology may not have been the primary concern at the time. There are interpretations which suggest issues around childbirth (very dangerous until modern times) and fear of disfigurement and disfigured individuals. What makes Frankenstein and the book so fascinating is how flexible interpretations can be. (For more about Frankenstein and flexibility, read Susan Tyler Hitchcock’s 2009 book, Frankenstein: a cultural history.)

There’s one more upcoming Frankenstein event, from The Frankenstein Bicentennial announcement webpage,

On June 14 and 15, 2016, the Brocher Foundation, Arizona State University, Duke University, and the University of Lausanne will host “Frankenstein’s Shadow,” a symposium in Geneva, Switzerland to commemorate the origin of Frankenstein and assess its influence in different times and cultures, particularly its resonance in debates about public policy governing biotechnology and medicine. These dates place the symposium almost exactly 200 years after Mary Shelley initially conceived the idea for Frankenstein on June 16, 1816, and in almost exactly the same geographical location on the shores of Lake Geneva.

If you’re interested in details such as the programme schedule, there’s this PDF,

Frankenstein¹s_ShadowConference

Enjoy!

Ingestible origami robot gets one step closer

Fiction, more or less seriously, has been exploring the idea of ingestible, tiny robots that can enter the human body for decades (Fantastic Voyage and Innerspace are two movie examples). The concept is coming closer to being realized as per a May 12, 2016 news item on phys.org,

In experiments involving a simulation of the human esophagus and stomach, researchers at MIT [Massachusetts Institute of Technology], the University of Sheffield, and the Tokyo Institute of Technology have demonstrated a tiny origami robot that can unfold itself from a swallowed capsule and, steered by external magnetic fields, crawl across the stomach wall to remove a swallowed button battery or patch a wound.

A May 12, 2016 MIT news release (also on EurekAlert), which originated the news item, provides some fascinating depth to this story (Note: Links have been removed),

The new work, which the researchers are presenting this week at the International Conference on Robotics and Automation, builds on a long sequence of papers on origami robots from the research group of Daniela Rus, the Andrew and Erna Viterbi Professor in MIT’s Department of Electrical Engineering and Computer Science.

“It’s really exciting to see our small origami robots doing something with potential important applications to health care,” says Rus, who also directs MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL). “For applications inside the body, we need a small, controllable, untethered robot system. It’s really difficult to control and place a robot inside the body if the robot is attached to a tether.”

Although the new robot is a successor to one reported at the same conference last year, the design of its body is significantly different. Like its predecessor, it can propel itself using what’s called a “stick-slip” motion, in which its appendages stick to a surface through friction when it executes a move, but slip free again when its body flexes to change its weight distribution.

Also like its predecessor — and like several other origami robots from the Rus group — the new robot consists of two layers of structural material sandwiching a material that shrinks when heated. A pattern of slits in the outer layers determines how the robot will fold when the middle layer contracts.

Material difference

The robot’s envisioned use also dictated a host of structural modifications. “Stick-slip only works when, one, the robot is small enough and, two, the robot is stiff enough,” says Guitron [Steven Guitron, a graduate student in mechanical engineering]. “With the original Mylar design, it was much stiffer than the new design, which is based on a biocompatible material.”

To compensate for the biocompatible material’s relative malleability, the researchers had to come up with a design that required fewer slits. At the same time, the robot’s folds increase its stiffness along certain axes.

But because the stomach is filled with fluids, the robot doesn’t rely entirely on stick-slip motion. “In our calculation, 20 percent of forward motion is by propelling water — thrust — and 80 percent is by stick-slip motion,” says Miyashita [Shuhei Miyashita, who was a postdoc at CSAIL when the work was done and is now a lecturer in electronics at the University of York, England]. “In this regard, we actively introduced and applied the concept and characteristics of the fin to the body design, which you can see in the relatively flat design.”

It also had to be possible to compress the robot enough that it could fit inside a capsule for swallowing; similarly, when the capsule dissolved, the forces acting on the robot had to be strong enough to cause it to fully unfold. Through a design process that Guitron describes as “mostly trial and error,” the researchers arrived at a rectangular robot with accordion folds perpendicular to its long axis and pinched corners that act as points of traction.

In the center of one of the forward accordion folds is a permanent magnet that responds to changing magnetic fields outside the body, which control the robot’s motion. The forces applied to the robot are principally rotational. A quick rotation will make it spin in place, but a slower rotation will cause it to pivot around one of its fixed feet. In the researchers’ experiments, the robot uses the same magnet to pick up the button battery.

Porcine precedents

The researchers tested about a dozen different possibilities for the structural material before settling on the type of dried pig intestine used in sausage casings. “We spent a lot of time at Asian markets and the Chinatown market looking for materials,” Li [Shuguang Li, a CSAIL postdoc] says. The shrinking layer is a biodegradable shrink wrap called Biolefin.

To design their synthetic stomach, the researchers bought a pig stomach and tested its mechanical properties. Their model is an open cross-section of the stomach and esophagus, molded from a silicone rubber with the same mechanical profile. A mixture of water and lemon juice simulates the acidic fluids in the stomach.

Every year, 3,500 swallowed button batteries are reported in the U.S. alone. Frequently, the batteries are digested normally, but if they come into prolonged contact with the tissue of the esophagus or stomach, they can cause an electric current that produces hydroxide, which burns the tissue. Miyashita employed a clever strategy to convince Rus that the removal of swallowed button batteries and the treatment of consequent wounds was a compelling application of their origami robot.

“Shuhei bought a piece of ham, and he put the battery on the ham,” Rus says. [emphasis mine] “Within half an hour, the battery was fully submerged in the ham. So that made me realize that, yes, this is important. If you have a battery in your body, you really want it out as soon as possible.”

“This concept is both highly creative and highly practical, and it addresses a clinical need in an elegant way,” says Bradley Nelson, a professor of robotics at the Swiss Federal Institute of Technology Zurich. “It is one of the most convincing applications of origami robots that I have seen.”

I wonder if they ate the ham afterwards.

Happily, MIT has produced a video featuring this ingestible, origami robot,

Finally, this team has a couple more members than the previously mentioned Rus, Miyashita, and Li,

…  Kazuhiro Yoshida of Tokyo Institute of Technology, who was visiting MIT on sabbatical when the work was done; and Dana Damian of the University of Sheffield, in England.

As Rus notes in the video, the next step will be in vivo (animal) studies.

The song is you: a McGill University, University of Cambridge, and Stanford University research collaboration

These days I’m thinking about sound, music, spoken word, and more as I prepare for a new art/science piece. It’s very early stages so I don’t have much more to say about it but along those lines of thought, there’s a recent piece of research on music and personality that caught my eye. From a May 11, 2016 news item on phys.org,

A team of scientists from McGill University, the University of Cambridge, and Stanford Graduate School of Business developed a new method of coding and categorizing music. They found that people’s preference for these musical categories is driven by personality. The researchers say the findings have important implications for industry and health professionals.

A May 10, 2016 McGill University news release, which originated the news item, provides some fascinating suggestions for new categories for music,

There are a multitude of adjectives that people use to describe music, but in a recent study to be published this week in the journal Social Psychological and Personality Science, researchers show that musical attributes can be grouped into three categories. Rather than relying on the genre or style of a song, the team of scientists led by music psychologist David Greenberg with the help of Daniel J. Levitin from McGill University mapped the musical attributes of song excerpts from 26 different genres and subgenres, and then applied a statistical procedure to group them into clusters. The study revealed three clusters, which they labeled Arousal, Valence, and Depth. Arousal describes intensity and energy in music; Valence describes the spectrum of emotions in music (from sad to happy); and Depth describes intellect and sophistication in music. They also found that characteristics describing music from a single genre (both rock and jazz separately) could be grouped in these same three categories.

The findings suggest that this may be a useful alternative to grouping music into genres, which is often based on social connotations rather than the attributes of the actual music. It also suggests that those in academia and industry (e.g. Spotify and Pandora) that are already coding music on a multitude of attributes might save time and money by coding music around these three composite categories instead.

The researchers also conducted a second study of nearly 10,000 Facebook users who indicated their preferences for 50 musical excerpts from different genres. The researchers were then able to map preferences for these three attribute categories onto five personality traits and 30 detailed personality facets. For example, they found people who scored high on Openness to Experience preferred Depth in music, while Extraverted excitement-seekers preferred high Arousal in music. And those who scored high on Neuroticism preferred negative emotions in music, while those who were self-assured preferred positive emotions in music. As the title from the old Kern and Hammerstein song suggests, “The Song is You”. That is, the musical attributes that you like most reflect your personality. It also provides scientific support for what Joni Mitchell said in a 2013 interview with the CBC: “The trick is if you listen to that music and you see me, you’re not getting anything out of it. If you listen to that music and you see yourself, it will probably make you cry and you’ll learn something about yourself and now you’re getting something out of it.”

The researchers hope that this information will not only be helpful to music therapists but also for health care professions and even hospitals. For example, recent evidence has showed that music listening can increase recovery after surgery. The researchers argue that information about music preferences and personality could inform a music listening protocol after surgery to boost recovery rates.

The article is another in a series of studies that Greenberg and his team have published on music and personality. This past July [2015], they published an article in PLOS ONE showing that people’s musical preferences are linked to thinking styles. And in October [2015], they published an article in the Journal of Research in Personality, identifying the personality trait Openness to Experience as a key predictor of musical ability, even in non-musicians. These series of studies tell us that there are close links between our personality and musical behavior that may be beyond our control and awareness.

Readers can find out how they score on the music and personality quizzes at www.musicaluniverse.org.

David M. Greenberg, lead author from Cambridge University and City University of New York said: “Genre labels are informative but we’re trying to transcend them and move in a direction that points to the detailed characteristics in music that are driving people preferences and emotional reactions.”

Greenberg added: “As a musician, I see how vast the powers of music really are, and unfortunately, many of us do not use music to its full potential. Our ultimate goal is to create science that will help enhance the experience of listening to music. We want to use this information about personality and preferences to increase the day-to-day enjoyment and peak experiences people have with music.”

William Hoffman in a May 11, 2016 article for Inverse describes the work in connection with recently released new music from Radiohead and an upcoming release from Chance the Rapper (along with a brief mention of Drake), Note: Links have been removed,

Music critics regularly scour Thesaurus.com for the best adjectives to throw into their perfectly descriptive melodious disquisitions on the latest works from Drake, Radiohead, or whomever. And listeners of all walks have, since the beginning of music itself, been guilty of lazily pigeonholing artists into numerous socially constructed genres. But all of that can be (and should be) thrown out the window now, because new research suggests that, to perfectly match music to a listener’s personality, all you need are these three scientific measurables [arousal, valence, depth].

This suggests that a slow, introspective gospel song from Chance The Rapper’s upcoming album could have the same depth as a track from Radiohead’s A Moon Shaped Pool. So a system of categorization based on Greenberg’s research would, surprisingly but rightfully, place the rap and rock works in the same bin.

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

The Song Is You: Preferences for Musical Attribute Dimensions Reflect Personality by David M. Greenberg, Michal Kosinski, David J. Stillwell, Brian L. Monteiro, Daniel J. Levitin, and Peter J. Rentfrow. Social Psychological and Personality Science, 1948550616641473, first published on May 9, 2016

This paper is behind a paywall.

Here’s a link to and a citation for the October 2015 paper

Personality predicts musical sophistication by David M. Greenberg, Daniel Müllensiefen, Michael E. Lamb, Peter J. Rentfrow. Journal of Research in Personality Volume 58, October 2015, Pages 154–158 doi:10.1016/j.jrp.2015.06.002 Note: A Feb. 2016 erratum is also listed.

The paper is behind a paywall and it looks as if you will have to pay for it and for the erratum separately.

Here’s a link to and a citation for the July 2015 paper,

Musical Preferences are Linked to Cognitive Styles by David M. Greenberg, Simon Baron-Cohen, David J. Stillwell, Michal Kosinski, Peter J. Rentfrow. PLOS [Public Library of Science ONE]  http://dx.doi.org/10.1371/journal.pone.0131151 Published: July 22, 2015

This paper is open access.

I tried out the research project’s website: The Musical Universe. by filling out the Musical Taste questionnaire. Unfortunately, I did not receive my results. Since the team’s latest research has just been reported, I imagine there are many people trying do the same thing. It might be worth your while to wait a bit if you want to try this out or you can fill out one of their other questionnaires. Oh, and you might want to allot at least 20 mins.

Nanoparticles for sustainable ways to grow crops

An April 29, 2016 news item on Nanowerk celebrates research into food production,

Scientists are working diligently to prepare for the expected increase in global population — and therefore an increased need for food production— in the coming decades. A team of engineers at Washington University in St. Louis has found a sustainable way to boost the growth of a protein-rich bean by improving the way it absorbs much-needed nutrients.

Ramesh Raliya, a research scientist, and Pratim Biswas, the Lucy & Stanley Lopata Professor and chair of the Department of Energy, Environmental & Chemical Engineering, both in the School of Engineering & Applied Science, discovered a way to reduce the use of fertilizer made from rock phosphorus and still see improvements in the growth of food crops by using zinc oxide nanoparticles.

The food under investigation is the mung bean,

Researchers at Washington University in St. Louis hope that nanoparticle technology can help reduce the need for fertilizer, creating a more sustainable way to grow crops such as mung beans. Courtesy: Washington University in St. Louis

Researchers at Washington University in St. Louis hope that nanoparticle technology can help reduce the need for fertilizer, creating a more sustainable way to grow crops such as mung beans. Courtesy: Washington University in St. Louis

An April 28, 2016 Washington University in St. Louis  news release (also on EurekAlert) by Beth Miller, which originated the news item, provides more detail,

The research was published April 7 [2016] in the Journal of Agricultural and Food Chemistry. Raliya said this is the first study to show how to mobilize native phosphorus in the soil using zinc oxide nanoparticles over the life cycle of the plant, from seed to harvest.

Food crops need phosphorus to grow, and farmers are using more and more phosphorus-based fertilizer as they increase crops to feed a growing world population. However, the plants can only use about 42 percent of the phosphorus applied to the soil, so the rest runs off into the water streams, where it grows algae that pollutes our water sources. In addition, nearly 82 percent of the world’s phosphorus is used as fertilizer, but it is a limited supply, Raliya says.

“If farmers use the same amount of phosphorus as they’re using now, the world’s supply will be depleted in about 80 years,” Raliya said. “Now is the time for the world to learn how to use phosphorus in a more sustainable manner.”

Raliya and his collaborators, including Jagadish Chandra Tarafdar at the Central Arid Zone Research Institute in Jodhpur, India, created zinc oxide nanoparticles from a fungus around the plant’s root that helps the plant mobilize and take up the nutrients in the soil. Zinc also is an essential nutrient for plants because it interacts with three enzymes that mobilize the complex form of phosphorus in the soil into a form that plants can absorb.

“Due to climate change, the daily temperature and rainfall amounts have changed,” Raliya said. “When they changed, the microflora in the soil are also changed, and once those are depleted, the soil phosphorus can’t mobilize the phosphorus, so the farmer applies more. Our goal is to increase the activity of the enzymes by several-fold, so we can mobilize the native phosphorus several-fold.”

When Raliya and the team applied the zinc nanoparticles to the leaves of the mung bean plant, it increased the uptake of the phosphorus by nearly 11 percent and the activity of the three enzymes by 84 percent to 108 percent. That leads to a lesser need to add phosphorus on the soil, Raliya said.

“When the enzyme activity increases, you don’t need to apply the external phosphorus, because it’s already in the soil, but not in an available form for the plant to uptake,” he said. “When we apply these nanoparticles, it mobilizes the complex form of phosphorus to an available form.”

The mung bean is a legume grown mainly in China, southeast Asia and India, where 60 percent of the population is vegetarian and relies on plant-based protein sources. The bean is adaptable to a variety of climate conditions and is very affordable for people to grow.

Raliya said 45 percent of the worldwide phosphorus use for agriculture takes place in India and China. Much of the phosphorus supply in developing countries is imported from the United States and Morocco-based rock phosphate mines.

“We hope that this method of using zinc oxide nanoparticles can be deployed in developing countries where farmers are using a lot of phosphorus,” Raliya said.

“These countries are dependent on the U.S. to export phosphorus to them, but in the future, the U.S. may have to help supply food, as well. If this crop can grow in a more sustainable manner, it will be helpful for everyone.”

“This is a broader effort under way at the nexus of food, energy and water,” Biswas said. “Nanoparticle technology enabled by aerosol science helps develop innovative solutions to address this global challenge problem that we face today.”

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

Enhancing the Mobilization of Native Phosphorus in the Mung Bean Rhizosphere Using ZnO Nanoparticles Synthesized by Soil Fungi by Ramesh Raliya, Jagadish Chandra Tarafdar, and Pratim Biswas. J. Agric. Food Chem., 2016, 64 (16), pp 3111–3118 DOI: 10.1021/acs.jafc.5b05224 Publication Date (Web): April 07, 2016

Copyright © 2016 American Chemical Society

This paper is behind a paywall.

Possible nanoparticle-based vaccine/microbiocide for herpes simplex virus-2

An April 27, 2016 news item on ScienceDaily describes a new therapeutic and preventative technology for herpes,

An effective vaccine against the virus that causes genital herpes has evaded researchers for decades. But now, researchers from the University of Illinois at Chicago [UIC] working with scientists from Germany have shown that zinc-oxide nanoparticles shaped like jacks can prevent the virus from entering cells, and help natural immunity to develop.

“We call the virus-trapping nanoparticle a microbivac, because it possesses both microbicidal and vaccine-like properties,” says corresponding author Deepak Shukla, professor of ophthalmology and microbiology & immunology in the UIC College of Medicine. “It is a totally novel approach to developing a vaccine against herpes, and it could potentially also work for HIV and other viruses,” he said.

The particles could serve as a powerful active ingredient in a topically-applied vaginal cream that provides immediate protection against herpes virus infection while simultaneously helping stimulate immunity to the virus for long-term protection, explained Shukla.

An April 27, 2016 UIC news release (also on EurekAlert), which originated the news item, provides more context for the work,

Herpes simplex virus-2, which causes serious eye infections in newborns and immunocompromised patients as well as genital herpes, is one of the most common human viruses. According to the Centers for Disease Control and Prevention, about 15 percent of people from ages 14-49 carry HSV-2, which can hide out for long periods of time in the nervous system. The genital lesions caused by the virus increase the risk for acquiring human immunodeficiency virus, or HIV.

“Your chances of getting HIV are three to four times higher if you already have genital herpes, which is a very strong motivation for developing new ways of preventing herpes infection,” Shukla said.

Treatments for HSV-2 include daily topical medications to suppress the virus and shorten the duration of outbreaks, when the virus is active and genital lesions are present. However, drug resistance is common, and little protection is provided against further infections. Efforts to develop a vaccine have been unsuccessful because the virus does not spend much time in the bloodstream, where most traditional vaccines do their work.

The news release goes on to provide technical details,

The tetrapod-shaped zinc-oxide nanoparticles, called ZOTEN, have negatively charged surfaces that attract the HSV-2 virus, which has positively charged proteins on its outer envelope. ZOTEN nanoparticles were synthesized using technology developed by material scientists at Germany’s Kiel University and protected under a joint patent with UIC.

When bound to the nanoparticles, HSV-2 cannot infect cells. But the bound virus remains susceptible to processing by immune cells called dendritic cells that patrol the vaginal lining. The dendritic cells “present” the virus to other immune cells that produce antibodies. The antibodies cripple the virus and trigger the production of customized killer cells that identify infected cells and destroy them before the virus can take over and spread.

The researchers showed that female mice swabbed with HSV-2 and an ointment containing ZOTEN had significantly fewer genital lesions than mice treated with a cream lacking ZOTEN. Mice treated with ZOTEN also had less inflammation in the central nervous system, where the virus can hide out.

The researchers were able to watch immune cells pry the virus off the nanoparticles for immune processing, using high-resolution fluorescence microscopy.

“It’s very clear that ZOTEN facilitates the development of immunity by holding the virus and letting the dendritic cells get to it,” Shukla said.

If found safe and effective in humans, a ZOTEN-containing cream ideally would be applied vaginally just prior to intercourse, Shukla said. But if a woman who had been using it regularly missed an application, he said, she may have already developed some immunity and still have some protection. Shukla hopes to further develop the nanoparticles to work against HIV, which like HSV-2 also has positively charged proteins embedded in its outer envelope.

ZOTEN particles are uniform in size and shape, making them attractive for use in other biomedical applications. The novel flame transport synthesis technology used to make them allows large-scale production, said Rainer Adelung, professor of nanomaterials at Kiel University. And, because no chemicals are used, the production process is green.

Adelung hopes to begin commercial production of ZOTEN through a startup company that will be run jointly with his colleagues at UIC.

Here’s an image of the particles, courtesy of UIC,

Zinc oxide tetrapod nanoparticles. Credit: Deepak Shukla

Zinc oxide tetrapod nanoparticles. Credit: Deepak Shukla

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

Intravaginal Zinc Oxide Tetrapod Nanoparticles as Novel Immunoprotective Agents against Genital Herpes by Thessicar E. Antoine, Satvik R. Hadigal, Abraam M. Yakoub, Yogendra Kumar Mishra, Palash Bhattacharya, Christine Haddad, Tibor Valyi-Nagy, Rainer Adelung, Bellur S. Prabhakar, and Deepak Shukla. The Journal of Immunology April 27, 2016 1502373  doi: 10.4049/jimmunol.1502373 Published online before print April 27, 2016

This paper is behind a paywall.

One final comment, it’s a long from a mouse vagina in this study to a human one.

Nucleic acid-based memory storage

We’re running out of memory. To be more specific, there are two problems: the supply of silicon and a limit to how much silicon-based memory can store. An April 27, 2016 news item on Nanowerk announces a nucleic acid-based approach to solving the memory problem,

A group of Boise State [Boise State University in Idaho, US] researchers, led by associate professor of materials science and engineering and associate dean of the College of Innovation and Design Will Hughes, is working toward a better way to store digital information using nucleic acid memory (NAM).

An April 25, 2016 Boise State University news release, which originated the news item, expands on the theme of computer memory and provides more details about the approach,

It’s no secret that as a society we generate vast amounts of data each year. So much so that the 30 billion watts of electricity used annually by server farms today is roughly equivalent to the output of 30 nuclear power plants.

And the demand keeps growing. The global flash memory market is predicted to reach $30.2 billion this year, potentially growing to $80.3 billion by 2025. Experts estimate that by 2040, the demand for global memory will exceed the projected supply of silicon (the raw material used to store flash memory). Furthermore, electronic memory is rapidly approaching its fundamental size limits because of the difficulty in storing electrons in small dimensions.

Hughes, with post-doctoral researcher Reza Zadegan and colleagues Victor Zhirnov (Semiconductor Research Corporation), Gurtej Sandhun (Micron Technology Inc.) and George Church (Harvard University), is looking to DNA molecules to solve the problem. Nucleic acid — the “NA” in “DNA” — far surpasses electronic memory in retention time, according to the researchers, while also providing greater information density and energy of operation.

Their conclusions are outlined in an invited commentary in the prestigious journal Nature Materials published earlier this month.

“DNA is the data storage material of life in general,” said Hughes. “Because of its physical and chemical properties, it also may become the data storage material of our lives.” It may sound like science fiction, but Hughes will participate in an invitation-only workshop this month at the Intelligence Advanced Research Projects Activity (IARPA) Agency to envision a portable DNA hard drive that would have 500 Terabytes of searchable data – that’s about the the size of the Library of Congress Web Archive.

“When information bits are encoded into polymer strings, researchers and manufacturers can manage and manipulate physical, chemical and biological information with standard molecular biology techniques,” the paper [in Nature Materials?] states.

Cost-competitive technologies to read and write DNA could lead to real-world applications ranging from artificial chromosomes, digital hard drives and information-management systems, to a platform for watermarking and tracking genetic content or next-generation encryption tools that necessitate physical rather than electronic embodiment.

Here’s how it works. Current binary code uses 0’s and 1’s to represent bits of information. A computer program then accesses a specific decoder to turn the numbers back into usable data. With nucleic acid memory, 0’s and 1’s are replaced with the nucleotides A, T, C and G. Known as monomers, they are covalently bonded to form longer polymer chains, also known as information strings.

Because of DNA’s superior ability to store data, DNA can contain all the information in the world in a small box measuring 10 x 10 x 10 centimeters cubed. NAM could thus be used as a sustainable time capsule for massive, scientific, financial, governmental, historical, genealogical, personal and genetic records.

Better yet, DNA can store digital information for a very long time – thousands to millions of years. Currently, usable information has been extracted from DNA in bones that are 700,000 years old, making nucleic acid memory a promising archival material. And nucleic acid memory uses 100 million times less energy than storing data electronically in flash, and the data can live on for generations.

At Boise State, Hughes and Zadegan are examining DNA’s stability under extreme conditions. DNA strands are subjected to temperatures varying from negative 20 degrees Celsius to 100 degrees Celsius, and to a variety of UV exposures to see if they can still retain their information. What they’re finding is that much less information is lost with NAM than with the current state of the industry.

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

Nucleic acid memory by Victor Zhirnov, Reza M. Zadegan, Gurtej S. Sandhu, George M. Church, & William L. Hughes. Nature Materials 15, 366–370 (2016)  doi:10.1038/nmat4594 Published online 23 March 2016

This paper is behind a paywall.

“One minus one equals zero” has been disproved

Two mirror-image molecules can be optically active according to an April 27, 2016 news item on ScienceDaily,

In 1848, Louis Pasteur showed that molecules that are mirror images of each other had exactly opposite rotations of light. When mixed in solution, they cancel the effects of the other, and no rotation of light is observed. Now, a research team has demonstrated that a mixture of mirror-image molecules crystallized in the solid state can be optically active.

An April 26, 2016 Northwestern University news release (also on EurekAlert), which originated the news item, expands on the theme,

In the world of chemistry, one minus one almost always equals zero.

But new research from Northwestern University and the Centre National de la Recherche Scientifique (CNRS) in France shows that is not always the case. And the discovery will change scientists’ understanding of mirror-image molecules and their optical activity.

Now, Northwestern’s Kenneth R. Poeppelmeier and his research team are the first to demonstrate that a mixture of mirror-image molecules crystallized in the solid state can be optically active. The scientists first designed and made the materials and then measured their optical properties.

“In our case, one minus one does not always equal zero,” said first author Romain Gautier of CNRS. “This discovery will change scientists’ understanding of these molecules, and new applications could emerge from this observation.”

The property of rotating light, which has been known for more than two centuries to exist in many molecules, already has many applications in medicine, electronics, lasers and display devices.

“The phenomenon of optical activity can occur in a mixture of mirror-image molecules, and now we’ve measured it,” said Poeppelmeier, a Morrison Professor of Chemistry in the Weinberg College of Arts and Sciences. “This is an important experiment.”

Although this phenomenon has been predicted for a long time, no one — until now — had created such a racemic mixture (a combination of equal amounts of mirror-image molecules) and measured the optical activity.

“How do you deliberately create these materials?” Poeppelmeier said. “That’s what excites me as a chemist.” He and Gautier painstakingly designed the material, using one of four possible solid-state arrangements known to exhibit circular dichroism (the ability to absorb differently the “rotated” light).

Next, Richard P. Van Duyne, a Morrison Professor of Chemistry at Northwestern, and graduate student Jordan M. Klingsporn measured the material’s optical activity, finding that mirror-image molecules are active when arranged in specific orientations in the solid state.

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

Optical activity from racemates by Romain Gautier, Jordan M. Klingsporn, Richard P. Van Duyne, & Kenneth R. Poeppelmeier. Nature Materials (2016) doi:10.1038/nmat4628 Published online 18 April 2016

This paper is behind a paywall.