Tag Archives: ACS

Preserving art canvases (think Van Gogh, Picasso, Vermeer, and others) with nanomaterials

It has to be disconcerting to realize that your precious paintings are deteriorating day by day.  In a June 22, 2017 posting titled ‘Art masterpieces are turning into soap‘,

This piece of research has made a winding trek through the online science world. First it was featured in an April 20, 2017 American Chemical Society news release on EurekAlert,

A good art dealer can really clean up in today’s market, but not when some weird chemistry wreaks havoc on masterpieces [emphasis mine]. Art conservators started to notice microscopic pockmarks forming on the surfaces of treasured oil paintings that cause the images to look hazy. It turns out the marks are eruptions of paint caused, weirdly, by soap that forms via chemical reactions. Since you have no time to watch paint dry, we explain how paintings from Rembrandts to O’Keefes are threatened by their own compositions — and we don’t mean the imagery.

Here’s the video,

Now, for the latest: canavases are deteriorating too. A May 23, 2018 news item on Nanowerk announces the latest research on the ‘canvas issue’ (Note: A link has been removed),

Paintings by Vincent van Gogh, Pablo Picasso and Johannes Vermeer have been delighting art lovers for years. But it turns out that these works of art might be their own worst enemy — the canvases they were painted on can deteriorate over time.

In an effort to combat this aging process, one group is reporting in ACS Applied Nano Materials (“Combined Nanocellulose/Nanosilica Approach for Multiscale Consolidation of Painting Canvases”) that nanomaterials can provide multiple layers of reinforcement.

A May 23, 2018 American Chemical Society (ACS) news release (also on EurekAlert), which originated the news item,  expands on the theme,

One of the most important parts of a painting is the canvas, which is usually made from cellulose-based fibers. Over time, the canvas ages, resulting in discoloration, wrinkles, tears and moisture retention, all greatly affecting the artwork. To combat aging, painting conservators currently place a layer of adhesive and a lining on the back of a painting, but this treatment is invasive and difficult to reverse. In previous work, Romain Bordes and colleagues from Chalmers University of Technology, Sweden, investigated nanocellulose as a new way to strengthen painting canvases on their surfaces. In addition, together with Krzysztof Kolman, they showed that silica nanoparticles can strengthen individual paper and cotton fibers. So, they next wanted to combine these two methods to see if they could further strengthen aging canvas.

The team combined polyelectrolyte-treated silica nanoparticles (SNP) with cellulose nanofibrils (CNF) for a one-step treatment. The researchers first treated canvases with acid and oxidizing conditions to simulate aging. When they applied the SNP-CNF treatment, the SNP penetrated and strengthened the individual fibers of the canvas, making it stiffer compared to untreated materials. The CNF strengthened the surface of the canvas and increased the canvas’s flexibility. The team notes that this treatment could be a good alternative to conventional methods.

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

Combined Nanocellulose/Nanosilica Approach for Multiscale Consolidation of Painting Canvases by Krzysztof Kolman, Oleksandr Nechyporchuk, Michael Persson, Krister Holmberg, and Romain Bordes. ACS Appl. Nano Mater., Article ASAP DOI: 10.1021/acsanm.8b00262 Publication Date (Web): April 26, 2018

Copyright © 2018 American Chemical Society

This image illustrating the researchers’ solution accompanies the article,

Courtesy: ACS

The European Union’s NanoRestART project was mentioned here before they’d put together this introductory video, which provides a good overview of the research,

For more details about the problems with contemporary and modern art, there’s my April 4, 2016 posting when the NanoRestART project was first mentioned here and there’s my Jan. 10, 2017 posting which details research into 3D-printed art and some of the questions raised by the use of 3D printing and other emerging technologies in the field of contemporary art.

Shipwrecks being brought back to life with ‘smart nanotech’

The American Chemical Society (ACS) is holding its 256th meeting from August 19 – 22, 2018 in Boston, Massachusetts, US. This August 21, 2018 news item on Nanowerk announces a ‘shipwreck’ presentation at the meeting,

Thousands of shipwrecks litter the seafloor all over the world, preserved in sediments and cold water. But when one of these ships is brought up from the depths, the wood quickly starts deteriorating. Today, scientists report a new way to use “smart” nanocomposites to conserve a 16th-century British warship, the Mary Rose, and its artifacts. The new approach could help preserve other salvaged ships by eliminating harmful acids without damaging the wooden structures themselves.

An August 21, 2018 ACS press release (also on EurekAlert), which originated the news item, delves further into the research and scientists’ after hours (?) activities,

“This project began over a glass of wine with Eleanor Schofield, Ph.D., who is head of conservation at the Mary Rose Trust,” recalls Serena Corr, Ph.D., the project’s principal investigator. “She was working on techniques to preserve the wood hull and assorted artifacts and needed a way to direct the treatment into the wood. We had been working with functional magnetic nanomaterials for applications in imaging, and we thought we might be able to apply this technology to the Mary Rose.”

The Mary Rose sank in 1545 off the south coast of England and remained under the seabed until she was salvaged in 1982, along with over 19,000 artifacts and pieces of timber. About 40 percent of the original structure survived. The ship and its artifacts give unique insights into Tudor seafaring and what it was like to live during that period. A state-of-the-art museum in Portsmouth, England, displays the ship’s hull and artifacts. A video about the ship and its artifacts can be viewed here.

While buried in the seabed, sulfur-reducing marine bacteria migrated into the wood of the Mary Rose and produced hydrogen sulfide. This gas reacted with iron ions from corroded fixtures like cannons to form iron sulfides. Although stable in low-oxygen environments, sulfur rapidly oxidizes in regular air in the presence of iron to form destructive acids. Corr’s goal was to avoid acid production by removing the free iron ions.

Once raised from the seabed, the ship was sprayed with cold water, which stopped it from drying out and prevented further microbial activity. The conservation team then sprayed the hull with different types of polyethylene glycol (PEG), a common polymer with a wide range of applications, to replace the water in the cellular structure of the wood and strengthen its outer layer.

Corr and her postdoctoral fellow Esther Rani Aluri, Ph.D., and Ph.D. candidate Enrique Sanchez at the University of Glasgow are devising a new family of tiny magnetic nanoparticles to aid in this process, in collaboration with Schofield and Rachel O’Reilly, Ph.D., at the University of Warwick. In their initial step, the team, led by Schofield, used synchrotron techniques to probe the nature of the sulfur species before turning the PEG sprays off, and then periodically as the ship dried. This was the first real-time experiment to closely examine  the evolution of oxidized sulfur and iron species. This accomplishment has informed efforts to design new targeted treatments for the removal of these harmful species from the Mary Rose wood.

The next step will be to use a nanocomposite based on core magnetic iron oxide nanoparticles that include agents on their surfaces that can remove the ions. The nanoparticles can be directly applied to the porous wood structure and guided to particular areas of the wood using external magnetic fields, a technique previously demonstrated for drug delivery. The nanocomposite will be encompassed in a heat-responsive polymer that protects the nanoparticles and provides a way to safely deliver them to and from the wood surface. A major advantage of this approach is that it allows for the complete removal of free iron and sulfate ions from the wood, and these nanocomposites can be tuned by tweaking their surfaces.

With this understanding, Corr notes, “Conservators will have, for the first time, a state-of-the-art quantitative and restorative method for the safe and rapid treatment of wooden artifacts. We plan to then transfer this technology to other materials recovered from the Mary Rose, such as textiles and leather.”

The researchers acknowledge funding from the Mary Rose Trust and the Leverhulme Trust.

There is a video about the Mary Rose produced by Agence France Presse (AFP) and published on Youtube in May 2013,

Here’s the text from AFP Mary Rose entry on Youtube,

The relics from the Mary Rose, the flagship of England’s navy when it sank in 1545 as a heartbroken king Henry VIII watched from the shore, have finally been reunited with the famous wreck in a new museum offering a view of life in Tudor times. Duration: 02:35

One more thing: Canadian shipwrecks

We don’t have a ‘Henry VIII’ story or ‘smart nano and shipwrecks’ story but we do have a federal agency devoted to underwater archaeology, Parks Canada Underwater Archaeology webpage,

Underwater archaeology deals with archaeological sites found below the surface of oceans, rivers, and lakes and on the foreshore. In addition to shipwrecks, underwater archaeologists study submerged aboriginal sites such as fish weirs and middens; remains of historic structures such as wharves, canal locks, and marine railways; sunken aircraft; and other submerged cultural heritage resources.

Underwater archaeology shares the same methodology and principles as archaeology carried out on land sites. All archaeology involves the careful study of artefacts, structures and features to reconstruct and explain the lives of people in the past. However, because it is carried out in a more challenging environment, underwater archaeological fieldwork is more complex than land archaeology.

Specialized techniques and equipment are required to work productively underwater. Staying warm during long dives is a constant concern, so underwater archaeologists often use masks that cover their entire faces, dry suits worn over layers of warm clothing, or in cases where the water is extremely cold, such as the excavation in Red Bay (Labrador), wet suits supplied with a flow of hot water. Underwater communication systems are used to talk to people on the surface or to other divers. Removing sediments covering underwater sites requires the controlled use of specially designed equipment such as suction airlifts and small dredges. Recording information underwater presents its own challenges. Special underwater paper is used for notes and drawings, while photo and video cameras are placed in waterproof housings.

Underwater archaeological fieldwork includes remote-sensing surveys using geophysical techniques, diving surveys to locate and map sites, site monitoring, and excavation. The success of an underwater archaeological project rests on accurate documentation of all aspects of the process. Meticulous mapping and recording are particularly essential when excavation is required, as artefacts and other physical evidence are permanently removed from their original contexts. Archaeologists aim to be able to reconstruct the entire site from the records they generate during fieldwork.

Underwater archeology with Marc-André Bernier

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There’s also a podcast interview with Marc-André Bernier where he discusses an important Canadian shipwreck, from the Library and Archives Canada, Underwater Canada: Investigating Shipwrecks webpage (podcast length 27:25), here’s the transcript for those who prefer reading,

Shipwrecks have stirred up interest in Canada’s maritime heritage for many decades. 2014 marks the 100th anniversary of the sinking of the Empress of Ireland, one of Canada’s worst maritime disasters.

In this episode, Marc-André Bernier, Chief of Parks Canada’s Underwater Archaeology Service, joins us to discuss shipwrecks, their importance in Canadian history, and how LAC plays an important role in researching, discovering and investigating them.

Podcast Transcript

Underwater Canada: Investigating Shipwrecks

Jessica Ouvrard: Welcome to “Discover Library and Archives Canada: Your History, Your Documentary Heritage.” I’m your host, Jessica Ouvrard. Join us as we showcase the treasures from our vaults; guide you through our many services; and introduce you to the people who acquire, safeguard and make known Canada’s documentary heritage.

Canada has a rich maritime history filled with many tragedies, from small boats [lost] in the Great Lakes, to the sinking of the Empress of Ireland in the St. Lawrence River, to Sir John Franklin’s doomed expeditions in the Arctic. The shipwrecks capture our imaginations and evoke images of tragedy, heroism, mystery and discovery. 2014 also marks the 100th anniversary of the sinking of the Empress of Ireland.

Marc-André Bernier, Chief of Parks Canada’s Underwater Archaeology Service, is joining us to discuss shipwrecks and their significance in Canada’s history, and LAC’s important role in the research, discovery and investigation of these shipwrecks.

Hello, Marc-André Bernier. Thank you for coming today.

Marc-André Bernier: My pleasure. Hello to you.

JO: For those who don’t know much about underwater archaeology, can you explain what it is and the risks and challenges that it presents?

MAB: I’ll start with the challenges rather than the risks, because there are obviously risks, but we try to minimize them. Diving is inherently risky. But I’ll start with the challenges because they are, to a certain extent, what characterize underwater archaeology.

We face a series of challenges that are more complicated, that make our work much more complicated than terrestrial archaeology. We work on water and underwater, and our working conditions are dictated by what happens outside, by nature. We can’t work every day on the water, especially if our work involves the sea or the ocean, for example. And when we work underwater, we have to deal with constraints in terms of time and sometimes visibility. That means that we have to be extremely well organized. Preparation is crucial. Logistics are crucial.

In terms of preparation, we need to properly prepare our research using archives and so on, but we also have to be prepared in terms of knowing what’s going on in the field. We need to know the environmental conditions and diving conditions, even when we can’t dive. Increasingly, the work involves heading into deeper areas that can only be reached by robots, by remotely operated equipment. So we have to be able to adapt.

We have to be very precise and very organized because sometimes we have only a few minutes to access a site that will tell us many historical secrets. So we have to come very well prepared.

And when we dive, we’re working in a foreign environment. We have to be good divers, yes, but we also have to have access to tools that will give us access to information. We have to take into account currents, darkness, and so on. The work is really very challenging. But with the rapid development of new technologies in recent years, we have access to more and more tools. We do basically the same work as archaeologists on land. However, the work is done in a completely different environment.

JO: A bit hostile in fact.

MAB: A bit hostile, but with sites, objects and information that are not accessible elsewhere. So there’s an opportunity to learn about history in a different way, and in some cases on a much larger scale.

JO: With all the maritime traffic in Canada, there must have been many accidents. Can you talk about them and give us an idea of the number?

MAB: People don’t realize that we’re a maritime country. We are a country that has evolved and developed around water. This was true even before the Europeans arrived. The First Nations often travelled by water. That travel increased or developed differently, if you will, when the Europeans arrived.

The St. Lawrence River, for example, and the Atlantic provinces were the point of entry and the route. We refer to different waterways, such as the Ottawa and Richelieu rivers. They constituted the route. So, there was heavy traffic, which meant many accidents. We’re talking about probably tens of thousands of shipwrecks if we include the Great Lakes and all the coasts of Canada. Since Canada has the longest coastline in the world, there is potential for shipwrecks. Only a small number of those shipwrecks have been found, but some are very significant and extremely impressive as well.

JO: Are there also many military ships, or is it more…?

MAB: That’s another thing that people don’t realize. There have been many military confrontations in Canadian waters, dating back to the New France era, or when Phips (Sir William Phips) arrived at Quebec City in 1690 and laid siege to the city. He arrived by ship and lost ships when he returned. During the Conquest, there were naval confrontations in Louisbourg, Nova Scotia; in Chaleur Bay; and even at Quebec City. Then, in the War of 1812, the Great Lakes were an extremely important maritime theatre of war in terms of naval battles. There are a number of examples in the Richelieu River.

Then we have the Second World War, with ships and German submarines. We all know the stories of the submarines that came inside the Gulf. So there are many military shipwrecks, from the New France era onward.

JO: What were the most significant shipwrecks in Canada? Have all the shipwrecks been found or…?

MAB: No. There are still shipwrecks that remain to be found. These days at Parks Canada, we’ve been looking for two of the shipwrecks that are considered among the most significant in the country: the HMS Erebus and the HMS Terror, Sir John Franklin’s ships lost in the Arctic. Franklin left England in 1845 to find the Northwest Passage, and he was never heard from again. Those are examples of significant shipwrecks that haven’t been found.

However, significance is always relative. A shipwreck may be very significant, especially if there is loss of life. It’s a tragic event that is deeply affecting. There are many shipwrecks that may not be seen as having national historic significance. However, at the local level, they are tragic stories that have very deep significance and that have profoundly affected an area.

That being said, there are ships that bear witness to memorable moments in the history of our country. Among the national historic sites of shipwrecks are, if we go back, the oldest shipwrecks: the Basque wrecks at Red Bay, Labrador, where whales were hunted in the 16th century. It’s even a UNESCO world heritage site. Then, from the New France era, there’s the Corossol from 1693 and the Phips wrecks from 1690. These are very significant shipwrecks.

Also of great significance are the Louisbourg shipwrecks, the battle site, the Battle of the Restigouche historic site, as well as shipwrecks such as the Hamilton and Scourge from the War of 1812. For all practical purposes, those shipwrecks are intact at the bottom of Lake Ontario. And the Franklin shipwrecks-even if they still haven’t been found-have been declared of national historic significance.

So there’s a wide range of shipwrecks that are significant, but there are thousands and thousands of shipwrecks that have significance. A shipwreck may also be of recreational significance. Some shipwrecks may be a little less historically significant, but for divers, they are exceptional sites for appreciating history and for having direct contact with history. That significance matters.

JO: Yes, they have a bit of a magical side.

MAB: They have a very magical side. When we dive shipwrecks, we travel through history. They give us direct access to our past.

JO: Yes. I imagine that finding a shipwreck is a bit like finding a needle in a haystack?

MAB: It can sometimes be a needle in a haystack, but often it’s by chance. Divers will sometimes stumble upon remains, and it leads to the discovery of a shipwreck. But usually, when we’re looking for a shipwreck, we have to start at the beginning and go to the source. We have to begin with the archives. We have to start by doing research, trying to find every small clue because searching in water over a large area is very difficult and complicated. We face logistical and environmental obstacles in our working conditions. It’s also expensive. We need to use ships and small boats.

There are different ways to find shipwrecks. At one extreme is a method that is technologically very simple. We dive and systematically search an area, if it’s not too deep. At the other extreme, we use the most sophisticated equipment. Today we have what we call robotic research vehicles. It is as sophisticated as launching the device, which is a bit like a self-guided torpedo. We launch it and recover it a few hours later. It carries out a sonar sweep of the bottom along a pre-programmed path. Between the two, we have a range of methods.

Basically, we have to properly define the boundaries of the area. It’s detective work. We have to try to recreate the events and define our search area, then use the proper equipment. The side-scan sonar gives us an image, and magnetometers detect metal. We have to decide which of the tools we’ll use. If we don’t do the research beforehand, we’ll lose a great deal of time.

JO: Have you used the LAC collections in your research, and what types of documents have you found?

MAB: Yes, as often as possible. We try to use the off-site archives, but it’s important to have access to the sources. Our research always starts with the archives. As for the types of documents, I mentioned the Basque documents that were collected through Library and Archives Canada. I’ve personally used colonial archives a lot. For the Corossol sinking in 1693, I remember looking at documents and correspondence that talked about the French recovery from the shipwreck the year after 1693, and the entire Phips epic.

At LAC, there’s a copy of the paintings of Creswell [Samuel Gurney Cresswell], who was an illustrator, painter, and also a lieutenant, in charge of doing illustrations during the HMS Investigator’s journey through the Arctic. So there’s a wide variety of documents, and sometimes we are surprised by the personal correspondence, which gives us details that official documents can’t provide.

JO: How do these documents help you in your research?

MAB: The archival records are always surprising. They help us in every respect. You have to see archaeology as detective work. Every detail is significant. It can be the change in topographical names on old maps that refer to events. There are many “Wreck Points” or “Pointe à la barque,” “Anse à la barque,” and so on. They refer to events. People named places after events. So we can always be surprised by bits of information that seem trivial at first.

It ranges from information on the sites and on the events that led to a shipwreck, to what happened after the sinking and what happened overall. What we want is not only to understand an event, but also to understand the event in the larger context of history, such as the history of navigation. Sometimes, the records provide that broader information.

It ranges from the research information to the analysis afterward: what we have, what we found, what it means and what it says about our history. That’s where the records offer limitless possibilities. We always have surprises. That’s why we enjoy coming to the archives, because we never know what we’ll discover.

JO: Yes, it’s always great to open a box.

MAB: It’s like Christmas. It’s like Christmas when we start delving into archival records, and it’s a sort of prelude to what happens in archaeology. When we reach a site, we’re always excited by what the site has to offer. But we have to be prepared to understand it. That’s why preparation using archives is extremely important to our work.

JO: In terms of LAC sources, do you often look at historical maps? Do you look at the different ones, because we have quite a large collection…

MAB: Quite exceptional, yes.

JO: … from the beginning until now?

MAB: Yes. They provide a lot of information, and we use them, like all sources, as much as possible. We look for different things on the maps. Obviously, we look for places that may show shipwreck locations. These maps may also show the navigation corridors or charts. The old charts show anchorages and routes. They help us recreate navigation habits, which helps us understand the navigation and maritime mindset of the era and gives us clues as to where the ships went and where they were lost.

These maps give us that type of information. They also give us information on the topography and the names of places that have changed over the years. Take the example of the Corossol in the Sept-Îles bay. One of the islands in that bay is called Corossol. For years, people looked for the French ship, the Corossol, near that island. However, Manowin Island was also called Corossol at that time and its name changed. So in the old maps, we traced the origin, and the ship lies much closer to that island. Those are some of the clues.

We also have magnificent maps. One in particular comes to mind. It was created in the 19th century on the Îles-de-la-Madeleine by an insurance company agent who made a wreck map of all the shipwrecks that he knew of. To us, that’s like candy. It’s one of the opportunities that maps provide. Maps are magnificent even if we don’t find clues. Just to admire them-they’re absolutely magnificent.

JO: From a historical point of view, why is it important to study shipwrecks?

MAB: Shipwrecks are in fact a microcosm. They represent a small world. During the time of the voyage, there was a world of its own inside the ship. That in itself is interesting. How did people live on board? What were they carrying? These are clues. The advantage of a shipwreck is that it’s like a Polaroid, a fixed image of a specific point in time. When we study a city such as Quebec City that has been continuously occupied, sometimes it’s difficult to see the separation between eras, or even between events. A shipwreck shows a specific time and specific place.

JO: And it’s frozen in time.

MAB: And it’s frozen in time. So here’s an image, in 1740, what did we have? Of course, we find objects made in other eras that were still in use in that time period. But it really gives us a fixed image, a capsule. We often have an image of a time capsule. It’s very useful, because it’s very rare to have these mini Pompeiis, and we have them underwater. It’s absolutely fascinating and interesting. It’s one of the contributions of underwater archaeology.

The other thing is that we don’t necessarily find the same type of material underwater as on land. The preservation conditions are completely different. On land, we find a great deal of metal. Iron stays fairly well preserved. But there’s not much organic material, unless the environment is extremely humid or extremely dry. Underwater, organic materials are very well preserved, especially if the sedimentation is fairly quick. I remember finding cartouches from 1690 that still had paper around them. So the preservation conditions are absolutely exceptional.

That’s why it’s important. The shipwrecks give us unique information that complements what we find on land, but they also offer something that can’t be found elsewhere.

JO: I imagine that there are preservation problems once it’s…

MAB: And that’s the other challenge.

JO: Yes, certainly.

MAB: If an object is brought up, we have to be ready to take action because it starts to degrade the moment we move it…

JO: It comes into contact with oxygen.

MAB: … Yes, but even when we move it, we expose it to a new corrosion, a new degradation. If we bring it to the surface right away, the process accelerates very quickly. We have to keep the object damp. We always have to be ready to take action. For example, if the water heats up too fast, micro-organisms may develop that accelerate the degradation. We then have to be ready to start preservation treatments, which can take years depending on the object. It’s an enormous responsibility and we have to be ready to handle it, if not, we destroy…

JO: … the heritage.

MAB: … what we are trying to save, and that’s to everyone’s detriment.

JO: Why do you think that people are so fascinated by archaeology, and more specifically by shipwrecks?

MAB: That’s also a paradox. We say that people aren’t interested in history. I am firmly convinced that people enjoy history and are interested in it. It must be well narrated, but people are interested in history. There’s already an interest in our past and in our links with the past. If people feel directly affected by the past, they’ll be fascinated by it. If we add on top of that the element of discovery, and archaeology is discovery, and all the myths surrounding artefact hunters…

JO: … treasure hunters.

MAB: … treasures, and so on. It’s an image that people have. Yes, we hunt treasure, but historical treasure. That image applies even more strongly to shipwrecks. There’s always that myth of the Spanish galleon filled with gold. Everyone thinks that all shipwrecks contain a treasure. That being said, there’s a fascination with discovery and with the past, and add on top of that the notion of the bottom of the sea: it’s the final frontier, where we can be surprised by what we discover. Since these discoveries are often remarkably well preserved, people are absolutely fascinated.

We grow up with stories of pirates, shipwrecks and lost ships. These are powerful images. A shipwreck is an image that captures the imagination. But a shipwreck, when we dive a shipwreck, we have direct contact with the past. People are fascinated by that.

JO: Are shipwreck sites accessible to divers?

MAB: Shipwreck sites are very accessible to divers. For us, it’s a basic principle. We want people to be able to visit these sites. Very rarely do we limit access to a site. We do, for example, in Louisbourg, Nova Scotia. The site is accessible, but with a guide. The site must be visited with a guide because the wrecks are unique and very fragile.

However, the basic principle is that, as I was saying, we should try to allow people to savour and absorb the spirit of the site. The best way is to visit the site. So there are sites that are accessible, and we try to make them accessible. We not only make them accessible, but we also promote them. We’re developing tools to provide information to people.

It’s also important to raise awareness. We have the opportunity and privilege to visit the sites. We have to ensure that our children and grandchildren have the same opportunity. So we have to protect and respect [the sites]. In that spirit, the sites have to be accessible because these experiences are absolutely incredible. With technology, we can now make them accessible not only to divers but also virtually, which is interesting and stimulating. Nowadays there are opportunities to make all these wonders available to as many people as possible, even if they don’t have the chance to dive.

JO: How long has Parks Canada been involved in underwater archaeology?

MAB: 2014 marks the 50th anniversary of the first dives at Fort Lennox in 1964 by Sean Gilmore and Walter Zacharchuk. That’s where it began. We’re going back there in August of this year, to the birthplace of underwater archaeology at Parks Canada.

We’re one of the oldest teams in the world, if we can say that. The first time an archaeologist dived a site was in 1960, so we were there basically at the beginning. Parks Canada joined the adventure very early on and it continues to be a part of it to this day. I believe that we’ve studied 225 sites across Canada, in the three oceans, the Great Lakes, rivers, truly across the entire country. We have a wealth of experience, and we’ll celebrate that this year by returning to Fort Lennox where it all began.

JO: Congratulations!

MAB: Thank you very much.

JO: 2014 marks the 100th anniversary of the sinking of the Empress of Ireland. What can you tell us about this maritime accident?

MAB: The story of the Empress begins on May 28, 1914. The Empress of Ireland left Quebec City for England with first, second and third class passengers on board. The Empress left Quebec in the late afternoon, with more than 1,400 passengers and crew on board. The ship headed down the St. Lawrence to Pointe au Père, a pilot station, because pilots were needed to navigate the St. Lawrence, given the reefs and hazards.

The pilot left the Empress at the Pointe au Père pilot station, and the ship resumed her journey. At the same time, the Storstad, a cargo ship, was heading in the opposite direction. In the fog, the two ships collided. The Storstad rammed the Empress of Ireland, creating a hole that immediately filled with water.

At that moment, it was after 1:30 a.m., so almost 2:00 a.m. It was night and foggy. The ship sank within 14 minutes, with a loss of 1,012 lives. Over 400 people survived, but over 1,000 people [died]. Many survivors were pulled from the water either by the ship that collided with the Empress or by other ships that were immediately dispatched.

JO: 14 minutes…

MAB: … In 14 minutes, the ship sank. The water rushed in and the ship sank extremely fast, leaving very little opportunity for people, especially those deeper inside the ship, to save themselves.

JO: So a disaster.

MAB: The greatest maritime tragedy in the history of the country.

JO: What’s your most unforgettable experience at an underwater archaeology site?

MAB :I’ve been doing this job for 24 years now, and I can tell you that I have had extraordinary experiences! There are two that stand out.

One was a Second World War plane in Longue-Pointe-de-Mingan that sank after takeoff. Five of the nine crew members drowned in the plane. In 2009, the plane was found intact at a depth of 40 metres. We knew that five of the crew members were still inside. What was absolutely fascinating, apart from the sense of contact and the very touching story, was that we had the opportunity, chance and privilege to have people who were on the beach when the event occurred, who saw the accident and who saw the soldiers board right beforehand. They told us how it happened and they are a direct link. They are part of the history and they experienced that history.

That was an absolutely incredible human experience. We worked with the American forces to recover the remains of the soldiers. Seeing people who had witnessed the event and who could participate 70 years later was a very powerful moment. Diving the wreck of that plane was truly a journey through time.

The other experience was with the HMS Investigator in the Arctic. That’s the ship that was credited with discovering the Northwest Passage. Actually, the crew found it, since the ship remained trapped in the ice and the crew continued on foot and were saved by another ship. The ship is practically intact up to the upper deck in ten metres of water. When you go down there, the area is completely isolated. The crew spent two winters there. On land we can see the remains of the equipment that they left on the ground. Three graves are also visible. So we can absorb the fact that they were in this environment, which was completely hostile, for two years, with the hope of being rescued.

And the ship: we then dive this amazing exploration machine that’s still upright, with its iron-clad prow to break the ice. It’s an icebreaker from the 1850s. We dive on the deck, with the debris left by the ice, the pieces of the ship completely sheared off by the ice. But underneath that is a complete ship, and on the inside, everything that the people left on board.

I often say that it’s like a time travel machine. We are transported and we can absorb the spirit of the site. That’s what I believe is important, and what we at Parks [Canada] try to impart, the spirit of the site. There was a historic moment, but it occurred at a site. That site must be seen and experienced for maximum appreciation. That’s part of the essence of the historic event and the site. On that site, we truly felt it.

JO: Thank you very much for coming to speak with us today. We greatly appreciate your knowledge of underwater Canada. Thank you.

MAB: Thank you very much.

JO: To learn more about shipwrecks, visit our website Shipwreck Investigations at lac-bac.gc.ca/sos/shipwrecks or read our articles on shipwrecks on thediscoverblog.com [I found other subjects but not shipwrecks in my admittedly brief search of the blog].

Thank you for joining us. I’m your host, Jessica Ouvrard, and you’ve been listening to “Discover Library and Archives Canada-where Canadian history, literature and culture await you.” A special thanks to our guest today, Marc-André Bernier.

A couple of comments. (1) It seems that neither Mr. Bernier nor his team have ever dived on the West Coast or west of Ottawa for that matter. (2) Given Bernier’s comments about oxygen and the degradation of artefacts once exposed to the air, I imagine there’s a fair of amount of excitement and interest in Corr’s work on ‘smart nanotech’ for shipwrecks.

The devil’s (i.e., luciferase) in the bioluminescent plant

The American Chemical Society (ACS) and the Massachusetts Institute of Technology (MIT) have both issued news releases about the latest in bioluminescence.The researchers tested their work on watercress, a vegetable that was viewed in almost sacred terms in my family; it was not easily available in Vancouver (Canada) when I was child.

My father would hunt down fresh watercress by checking out the Chinese grocery stores. He could spot the fresh stuff from across the street while driving at 30 miles or more per hour. Spotting it entailed an immediate hunt for parking (my father hated to pay so we might have go around the block a few times or more) and a dash out of the car to ensure that he got his watercress before anyone else spotted it. These days it’s much more easily available and, thankfully, my father has passed on so he won’t have to think about glowing watercress.

Getting back to bioluninescent vegetable research, the American Chemical Society’s Dec. 13, 2017 news release on EurekAlert (and as a Dec. 13, 2017 news item on ScienceDaily) makes the announcement,

The 2009 film “Avatar” created a lush imaginary world, illuminated by magical, glowing plants. Now researchers are starting to bring this spellbinding vision to life to help reduce our dependence on artificial lighting. They report in ACS’ journal Nano Letters a way to infuse plants with the luminescence of fireflies.

Nature has produced many bioluminescent organisms, however, plants are not among them. Most attempts so far to create glowing greenery — decorative tobacco plants in particular — have relied on introducing the genes of luminescent bacteria or fireflies through genetic engineering. But getting all the right components to the right locations within the plants has been a challenge. To gain better control over where light-generating ingredients end up, Michael S. Strano and colleagues recently created nanoparticles that travel to specific destinations within plants. Building on this work, the researchers wanted to take the next step and develop a “nanobionic,” glowing plant.

The team infused watercress and other plants with three different nanoparticles in a pressurized bath. The nanoparticles were loaded with light-emitting luciferin; luciferase, which modifies luciferin and makes it glow; and coenzyme A, which boosts luciferase activity. Using size and surface charge to control where the sets of nanoparticles could go within the plant tissues, the researchers could optimize how much light was emitted. Their watercress was half as bright as a commercial 1 microwatt LED and 100,000 times brighter than genetically engineered tobacco plants. Also, the plant could be turned off by adding a compound that blocks luciferase from activating luciferin’s glow.

Here’s a video from MIT detailing their research,

A December 13, 2017 MIT news release (also on EurekAlert) casts more light on the topic (I couldn’t resist the word play),

Imagine that instead of switching on a lamp when it gets dark, you could read by the light of a glowing plant on your desk.

MIT engineers have taken a critical first step toward making that vision a reality. By embedding specialized nanoparticles into the leaves of a watercress plant, they induced the plants to give off dim light for nearly four hours. They believe that, with further optimization, such plants will one day be bright enough to illuminate a workspace.

“The vision is to make a plant that will function as a desk lamp — a lamp that you don’t have to plug in. The light is ultimately powered by the energy metabolism of the plant itself,” says Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering at MIT and the senior author of the study

This technology could also be used to provide low-intensity indoor lighting, or to transform trees into self-powered streetlights, the researchers say.

MIT postdoc Seon-Yeong Kwak is the lead author of the study, which appears in the journal Nano Letters.

Nanobionic plants

Plant nanobionics, a new research area pioneered by Strano’s lab, aims to give plants novel features by embedding them with different types of nanoparticles. The group’s goal is to engineer plants to take over many of the functions now performed by electrical devices. The researchers have previously designed plants that can detect explosives and communicate that information to a smartphone, as well as plants that can monitor drought conditions.

Lighting, which accounts for about 20 percent of worldwide energy consumption, seemed like a logical next target. “Plants can self-repair, they have their own energy, and they are already adapted to the outdoor environment,” Strano says. “We think this is an idea whose time has come. It’s a perfect problem for plant nanobionics.”

To create their glowing plants, the MIT team turned to luciferase, the enzyme that gives fireflies their glow. Luciferase acts on a molecule called luciferin, causing it to emit light. Another molecule called co-enzyme A helps the process along by removing a reaction byproduct that can inhibit luciferase activity.

The MIT team packaged each of these three components into a different type of nanoparticle carrier. The nanoparticles, which are all made of materials that the U.S. Food and Drug Administration classifies as “generally regarded as safe,” help each component get to the right part of the plant. They also prevent the components from reaching concentrations that could be toxic to the plants.

The researchers used silica nanoparticles about 10 nanometers in diameter to carry luciferase, and they used slightly larger particles of the polymers PLGA and chitosan to carry luciferin and coenzyme A, respectively. To get the particles into plant leaves, the researchers first suspended the particles in a solution. Plants were immersed in the solution and then exposed to high pressure, allowing the particles to enter the leaves through tiny pores called stomata.

Particles releasing luciferin and coenzyme A were designed to accumulate in the extracellular space of the mesophyll, an inner layer of the leaf, while the smaller particles carrying luciferase enter the cells that make up the mesophyll. The PLGA particles gradually release luciferin, which then enters the plant cells, where luciferase performs the chemical reaction that makes luciferin glow.

The researchers’ early efforts at the start of the project yielded plants that could glow for about 45 minutes, which they have since improved to 3.5 hours. The light generated by one 10-centimeter watercress seedling is currently about one-thousandth of the amount needed to read by, but the researchers believe they can boost the light emitted, as well as the duration of light, by further optimizing the concentration and release rates of the components.

Plant transformation

Previous efforts to create light-emitting plants have relied on genetically engineering plants to express the gene for luciferase, but this is a laborious process that yields extremely dim light. Those studies were performed on tobacco plants and Arabidopsis thaliana, which are commonly used for plant genetic studies. However, the method developed by Strano’s lab could be used on any type of plant. So far, they have demonstrated it with arugula, kale, and spinach, in addition to watercress.

For future versions of this technology, the researchers hope to develop a way to paint or spray the nanoparticles onto plant leaves, which could make it possible to transform trees and other large plants into light sources.

“Our target is to perform one treatment when the plant is a seedling or a mature plant, and have it last for the lifetime of the plant,” Strano says. “Our work very seriously opens up the doorway to streetlamps that are nothing but treated trees, and to indirect lighting around homes.”

The researchers have also demonstrated that they can turn the light off by adding nanoparticles carrying a luciferase inhibitor. This could enable them to eventually create plants that shut off their light emission in response to environmental conditions such as sunlight, the researchers say.

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

A Nanobionic Light-Emitting Plant by Seon-Yeong Kwak, Juan Pablo Giraldo, Min Hao Wong, Volodymyr B. Koman, Tedrick Thomas Salim Lew, Jon Ell, Mark C. Weidman, Rosalie M. Sinclair, Markita P. Landry, William A. Tisdale, and Michael S. Strano. Nano Lett., 2017, 17 (12), pp 7951–7961 DOI: 10.1021/acs.nanolett.7b04369 Publication Date (Web): November 17, 2017

Copyright © 2017 American Chemical Society

This paper is behind a paywall.

Cyborg bacteria to reduce carbon dioxide

This video is a bit technical but then it is about work being presented to chemists at the American Chemical Society’s (ACS) at the 254th National Meeting & Exposition Aug. 20 -24, 2017,

For a more plain language explanation, there’s an August 22, 2017 ACS news release (also on EurekAlert),

Photosynthesis provides energy for the vast majority of life on Earth. But chlorophyll, the green pigment that plants use to harvest sunlight, is relatively inefficient. To enable humans to capture more of the sun’s energy than natural photosynthesis can, scientists have taught bacteria to cover themselves in tiny, highly efficient solar panels to produce useful compounds.

“Rather than rely on inefficient chlorophyll to harvest sunlight, I’ve taught bacteria how to grow and cover their bodies with tiny semiconductor nanocrystals,” says Kelsey K. Sakimoto, Ph.D., who carried out the research in the lab of Peidong Yang, Ph.D. “These nanocrystals are much more efficient than chlorophyll and can be grown at a fraction of the cost of manufactured solar panels.”

Humans increasingly are looking to find alternatives to fossil fuels as sources of energy and feedstocks for chemical production. Many scientists have worked to create artificial photosynthetic systems to generate renewable energy and simple organic chemicals using sunlight. Progress has been made, but the systems are not efficient enough for commercial production of fuels and feedstocks.

Research in Yang’s lab at the University of California, Berkeley, where Sakimoto earned his Ph.D., focuses on harnessing inorganic semiconductors that can capture sunlight to organisms such as bacteria that can then use the energy to produce useful chemicals from carbon dioxide and water. “The thrust of research in my lab is to essentially ‘supercharge’ nonphotosynthetic bacteria by providing them energy in the form of electrons from inorganic semiconductors, like cadmium sulfide, that are efficient light absorbers,” Yang says. “We are now looking for more benign light absorbers than cadmium sulfide to provide bacteria with energy from light.”

Sakimoto worked with a naturally occurring, nonphotosynthetic bacterium, Moorella thermoacetica, which, as part of its normal respiration, produces acetic acid from carbon dioxide (CO2). Acetic acid is a versatile chemical that can be readily upgraded to a number of fuels, polymers, pharmaceuticals and commodity chemicals through complementary, genetically engineered bacteria.

When Sakimoto fed cadmium and the amino acid cysteine, which contains a sulfur atom, to the bacteria, they synthesized cadmium sulfide (CdS) nanoparticles, which function as solar panels on their surfaces. The hybrid organism, M. thermoacetica-CdS, produces acetic acid from CO2, water and light. “Once covered with these tiny solar panels, the bacteria can synthesize food, fuels and plastics, all using solar energy,” Sakimoto says. “These bacteria outperform natural photosynthesis.”

The bacteria operate at an efficiency of more than 80 percent, and the process is self-replicating and self-regenerating, making this a zero-waste technology. “Synthetic biology and the ability to expand the product scope of CO2 reduction will be crucial to poising this technology as a replacement, or one of many replacements, for the petrochemical industry,” Sakimoto says.

So, do the inorganic-biological hybrids have commercial potential? “I sure hope so!” he says. “Many current systems in artificial photosynthesis require solid electrodes, which is a huge cost. Our algal biofuels are much more attractive, as the whole CO2-to-chemical apparatus is self-contained and only requires a big vat out in the sun.” But he points out that the system still requires some tweaking to tune both the semiconductor and the bacteria. He also suggests that it is possible that the hybrid bacteria he created may have some naturally occurring analog. “A future direction, if this phenomenon exists in nature, would be to bioprospect for these organisms and put them to use,” he says.

For more insight into the work, check out Dexter Johnson’s Aug. 22, 2017 posting on his Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineers] website),

“It’s actually a natural, overlooked feature of their biology,” explains Sakimoto in an e-mail interview with IEEE Spectrum. “This bacterium has a detoxification pathway, meaning if it encounters a toxic metal, like cadmium, it will try to precipitate it out, thereby detoxifying it. So when we introduce cadmium ions into the growth medium in which M. thermoacetica is hanging out, it will convert the amino acid cysteine into sulfide, which precipitates out cadmium as cadmium sulfide. The crystals then assemble and stick onto the bacterium through normal electrostatic interactions.”

I’ve just excerpted one bit, there’s more in Dexter’s posting.

Nanoparticle fertilizer and dreams of a new ‘Green’ revolution

There were hints even while it was happening that the ‘Green Revolution’ of the 1960s was not all it was touted to be. (For those who haven’t come across the term before, the Green Revolution was a better way to farm, a way that would feed everyone on earth. Or, that was the dream.)

Perhaps this time, they’ll be more successful. From a Jan. 15, 2017 news item on ScienceDaily, which offers a perspective on the ‘Green Revolution’ that differs from mine,

The “Green Revolution” of the ’60s and ’70s has been credited with helping to feed billions around the world, with fertilizers being one of the key drivers spurring the agricultural boom. But in developing countries, the cost of fertilizer remains relatively high and can limit food production. Now researchers report in the journal ACS Nano a simple way to make a benign, more efficient fertilizer that could contribute to a second food revolution.

A Jan. 25, 2017 American Chemical Society news release on EurekAlert, which originated the news item, expands on the theme,

Farmers often use urea, a rich source of nitrogen, as fertilizer. Its flaw, however, is that it breaks down quickly in wet soil and forms ammonia. The ammonia is washed away, creating a major environmental issue as it leads to eutrophication of water ways and ultimately enters the atmosphere as nitrogen dioxide, the main greenhouse gas associated with agriculture. This fast decomposition also limits the amount of nitrogen that can get absorbed by crop roots and requires farmers to apply more fertilizer to boost production. However, in low-income regions where populations continue to grow and the food supply is unstable, the cost of fertilizer can hinder additional applications and cripple crop yields. Nilwala Kottegoda, Veranja Karunaratne, Gehan Amaratunga and colleagues wanted to find a way to slow the breakdown of urea and make one application of fertilizer last longer.

To do this, the researchers developed a simple and scalable method for coating hydroxyapatite (HA) nanoparticles with urea molecules. HA is a mineral found in human and animal tissues and is considered to be environmentally friendly. In water, the hybridization of the HA nanoparticles and urea slowly released nitrogen, 12 times slower than urea by itself. Initial field tests on rice farms showed that the HA-urea nanohybrid lowered the need for fertilizer by one-half. The researchers say their development could help contribute to a new green revolution to help feed the world’s continuously growing population and also improve the environmental sustainability of agriculture.

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

Urea-Hydroxyapatite Nanohybrids for Slow Release of Nitrogen by Nilwala Kottegoda, Chanaka Sandaruwan, Gayan Priyadarshana, Asitha Siriwardhana, Upendra A. Rathnayake, Danushka Madushanka Berugoda Arachchige, Asurusinghe R. Kumarasinghe, Damayanthi Dahanayake, Veranja Karunaratne, and Gehan A. J. Amaratunga. ACS Nano, Article ASAP DOI: 10.1021/acsnano.6b07781 Publication Date (Web): January 25, 2017

Copyright © 2017 American Chemical Society

This paper is open access.

Curcumin: a scientific literature review concludes health benefits may be overstated

Given the number of times I’ve featured ‘curcumin research’, it seems only right to include this latest work. A Jan. 11, 2017 American Chemical Society (ACS) news release (also on EurekAlert) describes the results of a review of the scientific literature on curcumin’s (a constituent of turmeric) medicinal effectiveness,

Curcumin, a compound in turmeric, continues to be hailed as a natural treatment for a wide range of health conditions, including cancer and Alzheimer’s disease. But a new review of the scientific literature on curcumin has found it’s probably not all it’s ground up to be. The report in ACS’ Journal of Medicinal Chemistry instead cites evidence that, contrary to numerous reports, the compound has limited — if any — therapeutic benefit.

Turmeric, a spice often added to curries and mustards because of its distinct flavor and color, has been used for centuries in traditional medicine. Since the early 1990’s, scientists have zeroed in on curcumin, which makes up about 3 to 5 percent of turmeric, as the potential constituent that might give turmeric its health-boosting properties. More than 120 clinical trials to test these claims have been or are in the process of being run by clinical investigators. To get to the root of curcumin’s essential medicinal chemistry, the research groups of Michael A. Walters and Guido F. Pauli teamed up to extract key findings from thousands of scientific articles on the topic.

The researchers’ review of the vast curcumin literature provides evidence that curcumin is unstable under physiological conditions and not readily absorbed by the body, properties that make it a poor therapeutic candidate. Additionally, they could find no evidence of a double-blind, placebo-controlled clinical trial on curcumin to support its status as a potential cure-all. But, the authors say, this doesn’t necessarily mean research on turmeric should halt [emphasis mine]. Turmeric extracts and preparations could have health benefits, although probably not for the number of conditions currently touted. The researchers suggest that future studies should take a more holistic approach to account for the spice’s chemically diverse constituents that may synergistically contribute to its potential benefits.

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

The Essential Medicinal Chemistry of Curcumin by Kathryn M. Nelson, Jayme L. Dahlin, Jonathan Bisson, James Graham, Guido F. Pauli, and Michael A. Walters. J. Med. Chem., Article ASAP DOI: 10.1021/acs.jmedchem.6b00975 Publication Date (Web): January 11, 2017

Copyright © 2017 American Chemical Society

This paper is open access.

Sniffing for art conservation

The American Chemical Society (ACS) has produced a video titled, “How that ‘old book smell’ could save priceless artifacts” according to their Sept. 6, 2016 news release on EurekAlert,

Odor-detecting devices like Breathalyzers have been used for years to determine blood-alcohol levels in drunk drivers. Now, researchers are using a similar method to sniff out the rate of decay in historic art and artifacts. By tracking the chemicals in “old book smell” and similar odors, conservators can react quickly to preserve priceless art and artifacts at the first signs of decay. In this Speaking of Chemistry, Sarah Everts explains how cultural-heritage science uses the chemistry of odors to save books, vintage jewelry and even early Legos. …

Here’s the video,

Heritage Smells, the UK project mentioned in the video, is now completed but it was hosted by the University of Strathclyde and more project information can be found here.

Nanoparticles could make blood clot faster

It was the 252nd meeting for the American Chemical Society from Aug. 21 – 25, 2016 and that meant a flurry of news about the latest research. From an Aug. 23, 2016 news item on Nanowerk,

Whether severe trauma occurs on the battlefield or the highway, saving lives often comes down to stopping the bleeding as quickly as possible. Many methods for controlling external bleeding exist, but at this point, only surgery can halt blood loss inside the body from injury to internal organs. Now, researchers have developed nanoparticles that congregate wherever injury occurs in the body to help it form blood clots, and they’ve validated these particles in test tubes and in vivo [animal testing].

The researchers will present their work today [Aug. 22, 2016] at the 252nd National Meeting & Exposition of the American Chemical Society (ACS). ACS, the world’s largest scientific society, is holding the meeting here through Thursday. It features more than 9,000 presentations on a wide range of science topics.

An Aug. 22, 2016 American Chemical Society (ACS) news release (also on EurekAlert), which originated the news item, provided more detail,

“When you have uncontrolled internal bleeding, that’s when these particles could really make a difference,” says Erin B. Lavik, Sc.D. “Compared to injuries that aren’t treated with the nanoparticles, we can cut bleeding time in half and reduce total blood loss.”

Trauma remains a top killer of children and younger adults, and doctors have few options for treating internal bleeding. To address this great need, Lavik’s team developed a nanoparticle that acts as a bridge, binding to activated platelets and helping them join together to form clots. To do this, the nanoparticle is decorated with a molecule that sticks to a glycoprotein found only on the activated platelets.

Initial studies suggested that the nanoparticles, delivered intravenously, helped keep rodents from bleeding out due to brain and spinal injury, Lavik says. But, she acknowledges, there was still one key question: “If you are a rodent, we can save your life, but will it be safe for humans?”

As a step toward assessing whether their approach would be safe in humans, they tested the immune response toward the particles in pig’s blood. If a treatment triggers an immune response, it would indicate that the body is mounting a defense against the nanoparticle and that side effects are likely. The team added their nanoparticles to pig’s blood and watched for an uptick in complement, a key indicator of immune activation. The particles triggered complement in this experiment, so the researchers set out to engineer around the problem.

“We made a battery of particles with different charges and tested to see which ones didn’t have this immune-response effect,” Lavik explains. “The best ones had a neutral charge.” But neutral nanoparticles had their own problems. Without repulsive charge-charge interactions, the nanoparticles have a propensity to aggregate even before being injected. To fix this issue, the researchers tweaked their nanoparticle storage solution, adding a slippery polymer to keep the nanoparticles from sticking to each other.

Lavik also developed nanoparticles that are stable at higher temperatures, up to 50 degrees Celsius (122 degrees Fahrenheit). This would allow the particles to be stored in a hot ambulance or on a sweltering battlefield.

In future studies, the researchers will test whether the new particles activate complement in human blood. Lavik also plans to identify additional critical safety studies they can perform to move the research forward. For example, the team needs to be sure that the nanoparticles do not cause non-specific clotting, which could lead to a stroke. Lavik is hopeful though that they could develop a useful clinical product in the next five to 10 years.

It’s not unusual for scientists to give an estimate of 5 – 10 years before their science reaches the market.  Another popular range is 3 – 5 years.

Eggshell-based bioplastics

Adding eggshell nanoparticles to a bioplastic (shown above) increases the strength and flexibility of the material, potentially making it more attractive for use in the packaging industry. Credit: Vijaya Rangari/Tuskegee University

Adding eggshell nanoparticles to a bioplastic (shown above) increases the strength and flexibility of the material, potentially making it more attractive for use in the packaging industry. Credit: Vijaya Rangari/Tuskegee University

A March 15, 2016 news item on Nanowerk describes the research,

Eggshells are both marvels and afterthoughts. Placed on end, they are as strong as the arches supporting ancient Roman aqueducts. Yet they readily crack in the middle, and once that happens, we discard them without a second thought. But now scientists report that adding tiny shards of eggshell to bioplastic could create a first-of-its-kind biodegradable packaging material that bends but does not easily break.

The researchers present their work today [March 15, 2016] at the 251st National Meeting & Exposition of the American Chemical Society (ACS).

A March 15, 2016 ACS news release (also on EurekAlert), which originated the news item, describes the work further,

“We’re breaking eggshells down into their most minute components and then infusing them into a special blend of bioplastics that we have developed,” says Vijaya K. Rangari, Ph.D. “These nano-sized eggshell particles add strength to the material and make them far more flexible than other bioplastics on the market. We believe that these traits — along with its biodegradability in the soil — could make this eggshell bioplastic a very attractive alternative packaging material.”

Worldwide, manufacturers produce about 300 million tons of plastic annually. Almost 99 percent of it is made with crude oil and other fossil fuels. Once it is discarded, petroleum-based plastics can last for centuries without breaking down. If burned, these plastics release carbon dioxide into the atmosphere, which can contribute to global climate change.

As an alternative, some manufacturers are producing bioplastics — a form of plastic derived from cornstarch, sweet potatoes or other renewable plant-based sources — that readily decompose or biodegrade once they are in the ground. However, most of these materials lack the strength and flexibility needed to work well in the packaging industry. And that’s a problem since the vast majority of plastic is used to hold, wrap and encase products. So petroleum-based materials continue to dominate the market, particularly in grocery and other retail stores, where estimates suggest that up to a trillion plastic bags are distributed worldwide every year.

To find a solution, Rangari, graduate student Boniface Tiimob and colleagues at Tuskegee University experimented with various plastic polymers. Eventually, they latched onto a mixture of 70 percent polybutyrate adipate terephthalate (PBAT), a petroleum polymer, and 30 percent polylactic acid (PLA), a polymer derived from cornstarch. PBAT, unlike other oil-based plastic polymers, is designed to begin degrading as soon as three months after it is put into the soil.

This mixture had many of the traits that the researchers were looking for, but they wanted to further enhance the flexibility of the material. So they created nanoparticles made of eggshells. They chose eggshells, in part, because they are porous, lightweight and mainly composed of calcium carbonate, a natural compound that easily decays.

The shells were washed, ground up in polypropylene glycol and then exposed to ultrasonic waves that broke the shell fragments down into nanoparticles more than 350,000 times smaller than the diameter of a human hair. Then, in a laboratory study, they infused a small fraction of these particles, each shaped like a deck of cards, into the 70/30 mixture of PBAT and PLA. The researchers found that this addition made the mixture 700 percent more flexible than other bioplastic blends. They say this pliability could make it ideal for use in retail packaging, grocery bags and food containers — including egg cartons.

In addition to bioplastics, Rangari’s team is investigating using eggshell nanoparticles to enhance wound healing, bone regeneration and drug delivery.