Tag Archives: University of Copenhagen

Nanoscopic advance of colossal (!) significance by Danish quantum physicists

it’s not often you see the word ‘colossal’ in a science news release but it seems these Danish researchers are very excited about their breakthrough. From a January 26, 2023 news item on Nanowerk,

In a new breakthrough, researchers at the University of Copenhagen, in collaboration with Ruhr University Bochum, have solved a problem that has caused quantum researchers headaches for years. The researchers can now control two quantum light sources rather than one. Trivial as it may seem to those uninitiated in quantum, this colossal breakthrough allows researchers to create a phenomenon known as quantum mechanical entanglement. This in turn, opens new doors for companies and others to exploit the technology commercially.

A January 26, 2023 University of Copenhagen press release (also on EurekAlert), which originated the news item, provides context and more detail,

Going from one to two is a minor feat in most contexts. But in the world of quantum physics, doing so is crucial. For years, researchers around the world have strived to develop stable quantum light sources and achieve the phenomenon known as quantum mechanical entanglement – a phenomenon, with nearly sci-fi-like properties, where two light sources can affect each other instantly and potentially across large geographic distances. Entanglement is the very basis of quantum networks and central to the development of an efficient quantum computer.  

Today [January 26, 2023], researchers from the Niels Bohr Institute published a new result in the highly esteemed journal Science, in which they succeeded in doing just that. According to Professor Peter Lodahl, one of the researchers behind the result, it is a crucial step in the effort to take the development of quantum technology to the next level and to “quantize” society’s computers, encryption and the internet.

“We can now control two quantum light sources and connect them to each other. It might not sound like much, but it’s a major advancement and builds upon the past 20 years of work. By doing so, we’ve revealed the key to scaling up the technology, which is crucial for the most ground-breaking of quantum hardware applications,” says Professor Peter Lodahl, who has conducted research the area since 2001.  

The magic all happens in a so-called nanochip – which is not much larger than the diameter of a human hair – that the researchers also developed in recent years.

Quantum sources overtake the world’s most powerful computer 

Peter Lodahl’s group is working with a type of quantum technology that uses light particles, called photons, as micro transporters to move quantum information about.

While Lodahl’s group is a leader in this discipline of quantum physics, they have only been able to control one light source at a time until now. This is because light sources are extraordinarily sensitive to outside “noise”, making them very difficult to copy. In their new result, the research group succeeded in creating two identical quantum light sources rather than just one.

“Entanglement means that by controlling one light source, you immediately affect the other. This makes it possible to create a whole network of entangled quantum light sources, all of which interact with one another, and which you can get to perform quantum bit operations in the same way as bits in a regular computer, only much more powerfully,” explains postdoc Alexey Tiranov, the article’s lead author. 

This is because a quantum bit can be both a 1 and 0 at the same time, which results in processing power that is unattainable using today’s computer technology. According to Professor Lodahl, just 100 photons emitted from a single quantum light source will contain more information than the world’s largest supercomputer can process.

By using 20-30 entangled quantum light sources, there is the potential to build a universal error-corrected quantum computer – the ultimate “holy grail” for quantum technology, that large IT companies are now pumping many billions into.

Other actors will build upon the research

According to Lodahl, the biggest challenge has been to go from controlling one to two quantum light sources. Among other things, this has made it necessary for researchers to develop extremely quiet nanochips and have precise control over each light source.

With the new research breakthrough, the fundamental quantum physics research is now in place. Now it is time for other actors to take the researchers’ work and use it in their quests to deploy quantum physics in a range of technologies including computers, the internet and encryption.

“It is too expensive for a university to build a setup where we control 15-20 quantum light sources. So, now that we have contributed to understanding the fundamental quantum physics and taken the first step along the way, scaling up further is very much a technological task,” says Professor Lodahl.  

The research was conducted at the Danish National Research Foundation’s “Center of Excellence for Hybrid Quantum Networks (Hy-Q)” and is a collaboration between Ruhr University Bochum in Germany and the the University of Copenhagen’s Niels Bohr Institute.

Here’s a link to and a citation for this colossal research,

Collective super- and subradiant dynamics between distant optical quantum emitters by Alexey Tiranov, Vasiliki Angelopoulou, Cornelis Jacobus van Diepen, Björn Schrinski, Oliver August Dall’Alba Sandberg, Ying Wang, Leonardo Midolo, Sven Scholz, Andreas Dirk Wieck, Arne Ludwig, Anders Søndberg Sørensen, and Peter Lodahl. Science 26 Jan 2023 Vol 379, Issue 6630 pp. 389-393 DOI: 10.1126/science.ade9324

This paper is behind a paywall.

Coelacanth (a living fish fossil) may provide clue to making artificial organs for transplantation

An ancient fish called a ‘living fossil’ has helped researchers understand the basics of stem cells. This will further stem cell research and be a step in the direction of creating artificial organs. The coelacanth fish is 400 million years old. Photo: Canva. Courtesy: university of Copenhagen

A December 12, 2022 University of Copenhagen press release (also on EurekAlert) describes work which may have an impact on organ transplants,

A beating heart. A complicated organ that pumps blood around the body of animals and humans. Not exactly something you associate with a Petri dish in a laboratory.

But that may change in the future, and save the lives of people whose own organs fail. And the research is now one step closer to that.

To design artificial organs you first have to understand stem cells and the genetic instructions that govern their remarkable properties.

Professor Joshua Mark Brickman at the Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW) has unearthed the evolutionary origins of a master gene that acts on a network of genes instructing stem cells.

“The first step in stem cell research is to understand the gene regulatory network that supports so-called pluripotent stem cells. Understanding how their function was perfected in evolution can help provide knowledge about how to construct better stem cells,” says Joshua Mark Brickman.

Pluripotent stem cells are stem cells that can develop into all other cells. For example, heart cells. If we understand how the pluripotent stem cells develop into a heart, then we are one step closer to replicating this process in a laboratory.

What are stem cells?

Stem cells are non-specialized cells found in all multicellular organisms. Stem cells have two properties that distinguish them from other cell types. On the one hand, stem cells can undergo an unlimited number of cell divisions (mitoses), and on the other hand, stem cells have the ability to mature (differentiate) into several cell types.

A pluripotent stem cell is a cell that can develop into any other cell, such as a heart cell, hair cell or eye cell.

A ‘living fossil’ is the key to understanding stem cells

The pluripotent property of stem cells – meaning that the cells can develop into any other cell – is something that has traditionally been associated with mammals.

Now Joshua Mark Brickman and his colleagues have found that the master gene that controls stem cells and supports pluripotency also exists in a fish called coelacanth. In humans and mice this gene is called OCT4 and they found that the coelacanth version could replace the mammalian one in mouse stem cells.

In addition to the fact that the coelacanth is in a different class from mammals, it has also been called a ‘living fossil,’ since approximately 400 million years ago it developed into the form it has today. It has fins shaped like limbs and is therefore thought to resemble the first animals to move from the sea onto land.

“By studying its cells, you can go back in evolution, so to speak,” explains Assistant Professor Molly Lowndes.

Assistant Professor Woranop Sukparangsi continues: “The central factor controlling the gene network in stem cells is found in the coelacanth. This shows that the network already existed early in evolution, potentially as far back as 400 million years ago.”

And by studying the network in other species, such as this fish, the researchers can distill what the basic concepts that support a stem cell are.

“The beauty of moving back in evolution is that the organisms become simpler. For example, they have only one copy of some essential genes instead of many versions. That way, you can start to separate what is really important for stem cells and use that to improve how you grow stem cells in a dish,” says PhD student Elena Morganti.

Sharks, mice and kangaroos

In addition to the researchers finding out that the network around stem cells is much older than previously thought, and found in ancient species, they also learned how exactly evolution has modified the network of genes to support pluripotent stem cells.

The researchers looked at the stem cell genes from over 40 animals. For example sharks, mice and kangaroos. The animals were selected to provide a good sampling of the main branch points in evolution.

The researchers used artificial intelligence to build three-dimensional models of the different OCT4 proteins. The researchers could see that the general structure of the protein is maintained across evolution. While the regions of these proteins known to be important for stem cells do not change, species-specific differences in apparently unrelated regions of these proteins alter their orientation, potentially affecting how well it supports pluripotency.

“This a very exciting finding about evolution that would not have been possible prior to the advent of new technologies. You can see it as evolution cleverly thinking, we don not tinker with the ‘engine in the car’, but we can move the engine around and improve the drive train to see if it makes the car go faster,” says Joshua Mark Brickman.

The study is a collaborative project spanning Australia, Japan and Europe, with vital strategic partnerships with the groups of Sylvie Mazan at the Oceanological Observatory of Banyuls-sur-Mer in France and professor Guillermo Montoya at Novo Nordisk Foundation Center for Protein Research at University of Copenhagen.

Caption: Coelacanth-fish and other animals. Credit: By Woranop Sukparangsi Courtesy: University of Copenhagen

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

Evolutionary origin of vertebrate OCT4/POU5 functions in supporting pluripotency by Woranop Sukparangsi, Elena Morganti, Molly Lowndes, Hélène Mayeur, Melanie Weisser, Fella Hammachi, Hanna Peradziryi, Fabian Roske, Jurriaan Hölzenspies, Alessandra Livigni, Benoit Gilbert Godard, Fumiaki Sugahara, Shigeru Kuratani, Guillermo Montoya, Stephen R. Frankenberg, Sylvie Mazan & Joshua M. Brickman. Nature Communications volume 13, Article number: 5537 (2022) DOI: https://doi.org/10.1038/s41467-022-32481-z Published: 21 September 2022

This paper is open access.

7th annual Vancouver Nanomedicine Day, Sept. 17, 2020

Like so many events these days (COVID-19 days), this event put on by Canada’s NanoMedicines Innovation Network (NMIN) will be held virtually. Here’s more from the ‘Virtual’ Vancouver Nanomedicine Day 2020 event page on the NMIN website,

This world-class symposium, the sixth event of its kind, will bring together a record number (1000+) of renowned Canadian and international experts from across the nanomedicines field to:

  • highlight the discoveries and innovations in nanomedicines that are contributing to global progress in acute, chronic and orphan disease treatment and management;
  • present up-to-date diagnostic and therapeutic  nanomedicine approaches to addressing the challenges of COVID-19; and
  • facilitate discussion among nanomedicine researchers and innovators and UBC and NMIN clinician-scientists, basic researchers, trainees, and research partners.

Since 2014, Vancouver Nanomedicine Day has advanced nanomedicine research, knowledge mobilization and commercialization in Canada by sharing high-impact findings and facilitating interaction—among researchers, postdoctoral fellows, graduate students, and life science and startup biotechnology companies—to catalyze research collaboration.

Here are a few highlights from the ‘Virtual’ Vancouver Nanomedicine Day 2020 event page,

  • An introduction to nanomedicines by Dr. Emmanuel Ho (University of Waterloo)
  • A keynote address by an iconic nanomedicine innovator: Dr. Robert Langer (MIT, Department of Chemical Engineering)
  • Invited talks by internationally renowned experts, including Dr. Vito Foderà (The University of Copenhagen, Denmark); Dr. Lucia Gemma Delogu (University of Padova, Italy); and Dr. Christine Allen (University of Toronto)
  • A virtual poster competition, with cash prizes for the top posters
  • A debate on whether “nanomedicines are still the next big thing” between Marcel Bally (proponent) and Kishor Wasan (opponent)

You can get the Program in PDF.

Registration is free. But you must Register.

Here’s the event poster,

[downloaded from https://www.nanomedicines.ca/nmd-2020/]

I have a few observations, First, Robert Langer is a big deal. Here are a few highlights from his Wikipedia entry (Note: Links have been removed),

Robert Samuel Langer, Jr. FREng[2] (born August 29, 1948) is an American chemical engineer, scientist, entrepreneur, inventor and one of the twelve Institute Professors at the Massachusetts Institute of Technology.[3]

Langer holds over 1,350 granted or pending patents.[3][29] He is one of the world’s most highly cited researchers, having authored nearly 1,500 scientific papers, and has participated in the founding of multiple technology companies.[30][31]

Langer is the youngest person in history (at 43) to be elected to all three American science academies: the National Academy of Sciences, the National Academy of Engineering and the Institute of Medicine. He was also elected as a charter member of National Academy of Inventors.[32] He was elected as an International Fellow[2] of the Royal Academy of Engineering[2] in 2010.

It’s all about commercializing the research—or is it?

(This second observation is a little more complicated and requires a little context.) The NMIN is one of Canada’s Networks of Centres of Excellence (who thought that name up? …sigh), from the NMIN About page,

NMIN is funded by the Government of Canada through the Networks of Centres of Excellence (NCE) Program.

The NCEs seem to be firmly fixed on finding pathways to commercialization (from the NCE About page) Note: All is not as it seems,

Canada’s global economic competitiveness [emphasis mine] depends on making new discoveries and transforming them into products, services [emphasis mine] and processes that improve the lives of Canadians. To meet this challenge, the Networks of Centres of Excellence (NCE) offers a suite of programs that mobilize Canada’s best research, development and entrepreneurial [emphasis mine] expertise and focus it on specific issues and strategic areas.

NCE programs meet Canada’s needs to focus a critical mass of research resources on social and economic challenges, commercialize [emphasis mine] and apply more of its homegrown research breakthroughs, increase private-sector R&D, [emphasis mine] and train highly qualified people. As economic [emphasis mine] and social needs change, programs have evolved to address new challenges.

Interestingly, the NCE is being phased out,

As per the December 2018 NCE Program news, funding for the Networks of Centres of Excellence (NCE) Program will be gradually transferred to the New Frontiers in Research Fund (NFRF).

The new agency, NFRF, appears to have a completely different mandate, from the NFRF page on the Canada Research Coordinating Committee webspace,

The Canada Research Coordinating Committee designed the New Frontiers in Research Fund (NFRF) following a comprehensive national consultation, which involved Canadian researchers, research administrators, stakeholders and the public. NFRF is administered by the Tri-agency Institutional Programs Secretariat, which is housed within the Social Sciences and Humanities Research Council (SSHRC), on behalf of Canada’s three research granting agencies: the Canadian Institutes of Health Research, the Natural Sciences and Engineering Research Council and SSHRC.

The fund will invest $275 million over the next 5 years beginning in fiscal 2018-19, and $65 million ongoing, to fund international, interdisciplinary, fast-breaking and high-risk research.

NFRF is composed of three streams to support groundbreaking research.

  • Exploration generates opportunities for Canada to build strength in high-risk, high-reward and interdisciplinary research;
  • Transformation provides large-scale support for Canada to build strength and leadership in interdisciplinary and transformative research; and
  • International enhances opportunities for Canadian researchers to participate in research with international partners.

As you can see there’s no reference to commercialization or economic challenges.

Personally

Here at last is the second observation, I find it hard to believe that the government of Canada has given up on the idea of commercializing research and increasing the country’s economic competitiveness through research. Certainly, Langer’s virtual appearance at Vancouver Nanomedicine Day 2020, suggests that at least some corners of the Canadian research establishment are remaining staunchly entrepreneurial.

After all, the only Canadian government ministry with science in its name is this one: Innovation, Science and Economic Development Canada (ISED), as of Sept. 11, 2020.. (The other ‘science’ ministries are Natural Resources Canada, Environment and Climate Change Canada, Fisheries and Oceans Canada, Health Canada, and Agriculture and Agri-Food Canada.) ISED is not exactly subtle. Intriguingly the latest review on the state of science and technology in Canada was released on April 10, 2018 (from the April 10, 2018 Council of Canadian Academies CCA] news release),

Canada remains strong in research output and impact, capacity for R&D and innovation at risk: New expert panel report

While Canada is a highly innovative country, with a robust research base and thriving communities of technology start-ups, significant barriers—such as a lack of managerial skills, the experience needed to scale-up companies, and foreign acquisition of high-tech firms—often prevent the translation of innovation into wealth creation.[emphasis mine] The result is a deficit of technology companies growing to scale in Canada, and a loss of associated economic and social benefits.This risks establishing a vicious cycle, where successful companies seek growth opportunities elsewhere due to a lack of critical skills and experience in Canada guiding companies through periods of rapid expansion.

According to the CCA’s [2018 report] Summary webpage, it was Innovation, Science and Economic Development Canada which requested the report. (I wrote up a two-part commentary under one of my favourite titles: “The Hedy Lamarr of international research: Canada’s Third assessment of The State of Science and Technology and Industrial Research and Development in Canada.” Part 1 and Part 2)

I will be fascinated to watch the NFRF and science commercialization situations as they develop.

In the meantime, you can sign up for free to attend the ‘Virtual’ Vancouver Nanomedicine Day 2020.

Gold-144 is a polymorph

Au-144 (also known as Gold-144) is an iconic gold nanocluster according to a June 14, 2016 news item announcing its polymorphic nature on ScienceDaily,

Chemically the same, graphite and diamonds are as physically distinct as two minerals can be, one opaque and soft, the other translucent and hard. What makes them unique is their differing arrangement of carbon atoms.

Polymorphs, or materials with the same composition but different structures, are common in bulk materials, and now a new study in Nature Communications confirms they exist in nanomaterials, too. Researchers describe two unique structures for the iconic gold nanocluster Au144(SR)60, better known as Gold-144, including a version never seen before. Their discovery gives engineers a new material to explore, along with the possibility of finding other polymorphic nanoparticles.

A June 14, 2016 Columbia University news release (also on EurekAlert), which originated the news item, provides more insight into the work,

“This took four years to unravel,” said Simon Billinge, a physics professor at Columbia Engineering and a member of the Data Science Institute. “We weren’t expecting the clusters to take on more than one atomic arrangement. But this discovery gives us more handles to turn when trying to design clusters with new and useful properties.”

Gold has been used in coins and jewelry for thousands of years for its durability, but shrink it to a size 10,000 times smaller than a human hair [at one time one billionth of a meter or a nanometer was said to be 1/50,000, 1/60,000 or 1/100,000 of the diameter of a human hair], and it becomes wildly unstable and unpredictable. At the nanoscale, gold likes to split apart other particles and molecules, making it a useful material for purifying water, imaging and killing tumors, and making solar panels more efficient, among other applications.

Though a variety of nanogold particles and molecules have been made in the lab, very few have had their secret atomic arrangement revealed. But recently, new technologies are bringing these miniscule structures into focus.

Under one approach, high-energy x-ray beams are fired at a sample of nanoparticles. Advanced data analytics are used to interpret the x-ray scattering data and infer the sample’s structure, which is key to understanding how strong, reactive or durable the particles might be.

Billinge and his lab have pioneered a method, the atomic Pair Distribution Function (PDF) analysis, for interpreting this scattering data. To test the PDF method, Billinge asked chemists at the Colorado State University to make tiny samples of Gold-144, a molecule-sized nanogold cluster first isolated in 1995. Its structure had been theoretically predicted in 2009, and though never confirmed, Gold-144 has found numerous applications, including in tissue-imaging.

Hoping the test would confirm Gold-144’s structure, they analyzed the clusters at the European Synchrotron Radiation Source in Grenoble, and used the PDF method to infer their structure. To their surprise, they found an angular core, and not the sphere-like icosahedral core predicted. When they made a new sample and tried the experiment again, this time using synchrotrons at Brookhaven and Argonne national laboratories, the structure came back spherical.

“We didn’t understand what was going on, but digging deeper, we realized we had a polymorph,” said study coauthor Kirsten Jensen, formerly a postdoctoral researcher at Columbia, now a chemistry professor at the University of Copenhagen.

Further experiments confirmed the cluster had two versions, sometimes found together, each with a unique structure indicating they behave differently. The researchers are still unsure if Gold-144 can switch from one version to the other or, what exactly, differentiates the two forms.

To make their discovery, the researchers solved what physicists call the nanostructure inverse problem. How can the structure of a tiny nanoparticle in a sample be inferred from an x-ray signal that has been averaged over millions of particles, each with different orientations?

“The signal is noisy and highly degraded,” said Billinge. “It’s the equivalent of trying to recognize if the bird in the tree is a robin or a cardinal, but the image in your binoculars is too blurry and distorted to tell.”

“Our results demonstrate the power of PDF analysis to reveal the structure of very tiny particles,” added study coauthor Christopher Ackerson, a chemistry professor at Colorado State. “I’ve been trying, off and on, for more than 10 years to get the single-crystal x-ray structure of Gold-144. The presence of polymorphs helps to explain why this molecule has been so resistant to traditional methods.”

The PDF approach is one of several rival methods being developed to bring nanoparticle structure into focus. Now that it has proven itself, it could help speed up the work of describing other nanostructures.

The eventual goal is to design nanoparticles by their desired properties, rather than through trial and error, by understanding how form and function relate. Databases of known and predicted structures could make it possible to design new materials with a few clicks of a mouse.

The study is a first step.

“We’ve had a structure model for this iconic gold molecule for years and then this study comes along and says the structure is basically right but it’s got a doppelgänger,” said Robert Whetten, a professor of chemical physics at the University of Texas, San Antonio, who led the team that first isolated Gold-144. “It seemed preposterous, to have two distinct structures that underlie its ubiquity, but this is a beautiful paper that will persuade a lot of people.”

Here’s an image illustrating the two shapes,

Setting out to confirm the predicted structure of Gold-144, researchers discovered an entirely unexpected atomic arrangement (right). The two structures, described in detail for the first time, each have 144 gold atoms, but are uniquely shaped, suggesting they also behave differently. (Courtesy of Kirsten Ørnsbjerg Jensen)

Setting out to confirm the predicted structure of Gold-144, researchers discovered an entirely unexpected atomic arrangement (right). The two structures, described in detail for the first time, each have 144 gold atoms, but are uniquely shaped, suggesting they also behave differently. (Courtesy of Kirsten Ørnsbjerg Jensen)

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

Polymorphism in magic-sized Au144(SR)60 clusters by Kirsten M.Ø. Jensen, Pavol Juhas, Marcus A. Tofanelli, Christine L. Heinecke, Gavin Vaughan, Christopher J. Ackerson, & Simon J. L. Billinge.  Nature Communications 7, Article number: 11859  doi:10.1038/ncomms11859 Published 14 June 2016

This is an open access paper.

Heart urchin shells and air

This is a microscale (1 millionth) rather than a nanoscale (1 billionth) story but I find the idea of shells that are mostly composed of air quite intriguing. From a Nov. 10, 2015 news item on ScienceDaily,

Materials researchers love sea creatures. Mother-of-pearl provokes ideas for smooth surfaces, clams inspire gluey substances, shark’s skin is used to develop materials that reduce drag in water, and so on. Researchers have now found a model for strong, lightweight materials by diving below the sea surface to investigate a sea urchin cousin known as the heart urchin.

A Nov. 9, 2015 University of Copenhagen press release (also on EurekAlert), which originated the news item, provides more details,

Heart urchins (Echinocardium cordatum), also known as sea potatoes, measure up to 5 cm in diameter, are heart shaped and burrow in sand. They extend a channel to feed upon organic particles from the waters above their burrow. Like “regular” sea urchins, these “irregular” heart urchins are soft creatures that use their calcium carbonate exoskeletons to protect their otherwise edible bodies from predation. And as it turns out, their shells are unexpectedly robust.

The idea to study heart urchin shells dawned upon a vacationing Müter while he was walking down a Croatian beach. The paper-thin urchin shells were washed up onto the beach, and Müter [Dirk Müter, assistant professor in the Department of Chemistry’s NanoGeoScience research group] observed that they had astonishingly few blemishes despite being so thin.

To understand the sturdy calcium carbonate shells, Müter and his colleagues used a relatively new technology called x-ray microtomography. The technique was used to create three-dimensional images of the material contents, without having to break the shells up into pieces. The x-ray images are so fine that it is possible to distinguish structures of less than one-thousandth of a millimetre. This ultra fine resolution proved decisive in coming to understand the shell’s strength.

Anyone who has ever broken a piece of chalk knows that calcium carbonate is fragile. And, heart urchin shells consist of more air than chalk. In fact, as one gets up close to the shell material, it begins to resemble soapsuds. The material consists of an incredible number of microscopic cavities held together by slender calcium carbonate (chalk) struts. There are between 50,000 and 150,000 struts per cubic millimetre, and in some areas, the material is composed of up to 70% air.

Calcium carbonate can be many things, from unyielding marble to the soft and somewhat brittle chalk that we use to write with. While heart urchin shells and writing chalk share a similar porosity, the urchin shells are up to six times stronger than chalk. Müter’s studies demonstrate that heart urchin shells have a structure that nears a theoretical ideal for foam structure strength – a must for a creature that has evolved to withstand life under 10 metres of water and an additional 30 centimetres of sand.

Müter explains that to their great surprise, heart urchin shell strength varied between shell regions due to greater or lesser concentrations of struts within specific regions, not because of thinner or thicker struts.

“We found an example of a surprisingly simple construction principle. This is an easy way to build materials. It allows for great variation in structure and strength. And, it is very near optimal from a mechanical perspective,” states Assistant Professor Dirk Müter.

Müter and his NanoGeoScience colleagues expect that their new insights will serve to improve shock- absorbent materials among other outcomes.

Here is Müter holding up a sea potato or sea heart,

Caption: The heart urchin lives its entire life dug into the sea bottom. Its fragile looking calcium shell needs to withstand the combined pressure of half a meter of sand and a couple of meters water. Dirk Müter of University of copenhagen Department of Chemistry, discovered, that this makes it one of the toughest creatures known. Credit Photo: Jes Andersen/University of Copenhagen

Caption: The heart urchin lives its entire life dug into the sea bottom. Its fragile looking calcium shell needs to withstand the combined pressure of half a meter of sand and a couple of meters water. Dirk Müter of University of copenhagen Department of Chemistry, discovered, that this makes it one of the toughest creatures known. Credit Photo: Jes Andersen/University of Copenhagen

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

Microstructure and micromechanics of the heart urchin test from X-ray tomography by D. Müter, , H.O. Sørensen, J. Oddershede, K.N. Dalby, and S.L.S. Stipp. Acta Biomaterialia Volume 23, 1 September 2015, Pages 21–26 doi:10.1016/j.actbio.2015.05.007

This paper is behind a paywall.

First year Danish students achieve breakthrough with self-assembling molecular eletronics

This is in fact two stories. One features the students and an educational approach which is achieving some exciting results and the other features self-assembling electronics and the possibility of a step forward in the field. From an Aug. 17, 2015 University of Copenhagen press release on EurekAlert,

When researchers dream about electronics of the future, they more or less dream of pouring liquids into a beaker, stirring them together and decanting a computer out onto the table. This field of research is known as self-assembling molecular electronics. But, getting chemical substances to self-assemble into electronic components is just as complicated as it sounds. Now, a group of researchers has published their breakthrough within the field. The group consists of first-year nanoscience students from the University of Copenhagen.

Thomas Just Sørensen, an associate professor at the University of Copenhagen, spearheaded the research project. … Sørensen believes that the result will spawn new breakthroughs: “This is a clear step forward towards self-assembling electronics. By mixing solutions of the right substances, we automatically built structures that in principle could have been solar cells or transistors. What is more, is that they were built in the same way that nature builds such things as cell membranes,” says Sørensen.

Sørensen’s co-authors are the entire first-year of University of Copenhagen nanoscience students. This impressive feat is the result of a restructuring of the nanoscience programme in 2010, from a programme structured upon research-based instruction, to one that uses teaching-based research. For their first assignment, the students were simply asked to design, conduct and analyse a range of experiments. The new instructional type has shed research results every year since. However, it wasn’t until 2013 that a result was ready to be published.

“For us as a university, the big news is obviously that first year students conducted the research. But, we achieved a very significant result in molecular electronics as well,” states Thomas Just Sørensen.

The press release offers a description of bottom-up (self-assembling) vs. top-down engineering (standard practice) along with a few more details about the self-assembling ‘electronics’,

Electronics are normally produced in such a way that one “draws” components onto a silicon wafer and then removes all the bits that are not part of the electronic component. This is called “Top-down” production. Molecular electronics enables the production of transistors, resistors, LED screens, solar cells and so on, using chemistry-based methods. In principle, this means that electronics can become smaller, cheaper and more flexible, as well as environmentally sustainable. But whereas one can draw an integrated circuit on silicon, molecular components must self-organise into the correct structures. This is a major obstacle in the development of methods where molecules must join and self-organise in such a way that they can be found again, according to Sørensen.

“It doesn’t help to have a pile of transistors, if you don’t know which way they are turned. These cannot be combined in a way to make them work, and one won’t know which end to connect to electric current.”

The secret behind the breakthrough is… Soap. The molecular components that make self-assembling electronics possible are antifungal agents used in various disinfectants, creams and cosmetics. These cleansers kill fungi by disrupting the structures of their cell membranes. This same ability can be used to create order among molecular components. Sørensen and his students experimented by pouring a flood of various soaps, dish-soaps and washing powders together with component-like chemical substances. The mixtures were then poured out onto glass plates in order to investigate whether or not the “components” were organised by the various cleansing agents. And now they have been, says Sørensen.

“Our self-assembling electronics are a bit like putting cake layers, custard and frosting in a blender and having it all pop out of the blender as a perfectly formed layer cake,” says Thomas Just Sørensen.

In the long term, these new discoveries open the door to developing powerful and economical solar energy facilities, as well as improved screen technologies. That being said, the molecules used in the nanoscience programme had no electronic functionality. “If they did, we would have been on the cover of Science instead of in a ChemNanoMat article,” says Just Sørensen. Regardless, he remains confident.

“We were able to obtain a structure simply by mixing the right substances. Even random substances were able to organise well and layer, so that we now have complete control over where the molecules are, and in which direction they are oriented. The next step is to incorporate functionality within the layers,” says Associate Professor Sørensen. He is convinced that the next batch of challenges will make for perfect assignments for the many years of nanoscience students to come, and that like their current peers, these students will also have the opportunity to publish while in their first year of study.

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

Template-Guided Ionic Self-Assembled Molecular Materials and Thin Films with Nanoscopic Order by Marco Santella, Fatima Amini, Kristian B. Andreasen, Dunya S. Aswad, Helene Ausar, Lillian Marie Austin, Ilkay Bora, Ida M. I. Boye, Nikolaj K. Brinkenfeldt, Magnus F. Bøe, Emine Cakmak, Alen Catovic, Jonas M. Christensen, Jonas H. Dalgaard, Helena Maria D. Danielsen, Abdel H. El Bouyahyaoui, Sarah E. H. El Dib, Btihal El Khaiyat, Iqra Farooq, Freja K. Fjellerup, Gregers W. Frederiksen, Henriette R. S. Frederiksen, David Gleerup, Mikkel Gold, Morten F. Gruber, Mie Gylling, Vita Heidari, Mikkel Herzberg, U. Laurens D. Holgaard, Adam C. Hundahl, Rune Hviid, Julian S. Høhling, Fatima Z. Abd Issa, Nicklas R. Jakobsen, Rasmus K. Jakobsen, Benjamin L. Jensen, Phillip W. K. Jensen, Mikkel Juelsholt, Zhiyu Liao, Chung L. Le, Ivan F. Mayanja, Hadeel Moustafa, Charlie B. B. Møller, Cecilie L. Nielsen, Marius R. J. E. H. Nielsen, Søren S.-R. Nielsen, Markus J. Olsen, Bandula D. Paludan, Idunn Prestholm, Iliriana Qoqaj, Christina B. Riel, Tobias V. Rostgaard, Nora Saleh, Hannibal M. Schultz, Mark Standland, Jens S. Svenningsen, Rasmus Truels Sørensen, Jesper Visby, Emilie L. Wolff-Sneedorff, Malte Hee Zachariassen, Edmond A. Ziari, Henning O. Sørensen, and Thomas Just Sørensen. ChemNanoMat Volume 1, Issue 4, pages 253–258, August 2015 DOI: 10.1002/cnma.201500064 Article first published online: 2 JUL 2015

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This is an open access paper.

X-raying fungus on paper to conserve memory

Civilization is based on memory. Our libraries and archives serve as memories of how things are made, why we use certain materials rather than others, how the human body is put together, what the weather patterns have been, etc. For centuries we have preserved our memories on paper. While this has many advantages, there are some drawbacks including fungus infestations.

A July 21, 2015 news item on ScienceDaily describes how a technique used to x-ray rocks has provided insights into paper and its fungal infestations,

Believe it or not: X-ray works a lot better on rocks than on paper. This has been a problem for conservators trying to save historical books and letters from the ravages of time and fungi. They frankly did not know what they were up against once the telltale signs of vandals such as Dothidales or Pleosporales started to spot the surface of their priceless documents

Now Diwaker Jha, an imaging specialist from Department of Chemistry, University of Copenhagen, has managed to adapt methods developed to investigate interiors of rocks to work on paper too, thus getting a first look at how fungus goes about infesting paper. …

A July 21, 2015 University of Copenhagen press release (also on EurekAlert), which originated the news item, expands on the theme,

This is good news for paper conservators and others who wish to study soft materials with X-ray tomography. “Rocks are easy because they are hard. The X-ray images show a very good contrast between the solid and the pores or channels, which are filled with low density materials such as air or fluids. In this case, however, paper and fungi, both are soft and carbon based, which makes them difficult to distinguish,” says Diwaker.

Diwaker Jha is a PhD student in the NanoGeoScience group, which is a part of the Nano-Science Center at Department of Chemistry. He investigates methods to improve imaging techniques used by chemists and physicists to investigate how fluids move in natural porous materials. At a recent conference, he was presenting an analysis method he developed for X-ray tomography data, for which he was awarded the Presidential Scholar Award by the Microscopy Society of America. And this sparked interest with a conservator in the audience.

Hanna Szczepanowska works as a research conservator with the Smithsonian Institution in the USA. She had been wondering how fungi interact with the paper. Does it sit on the surface, or does it burrow deeper? If they are surface dwellers, it should be easy to just brush them off, but no such luck, says Jha.

“As it turns out, microscopic fungi that infest paper grow very much the same way as mushrooms on a forest floor. However, unlike mushrooms, where the fruiting body emerges out of the soil to the surface, here the fruiting bodies can be embedded within the paper fibres, making it difficult to isolate them. This is not great news for conservators because the prevalent surface cleaning approaches are not adequate,” explains Diwaker Jha.

In working out a way to see into the paper, Jha investigated a 17th century letter on a handmade sheet and a 1920 engraving on machine-made paper. Compared with mushrooms, these fungi are thousands of times smaller, which required an advanced X-ray imaging technique available at the European Synchrotron Radiation Facility (ESRF), Grenoble, France. The technique is very similar to medical tomography (CT scanning) done at hospitals but in Grenoble the X-ray is produced by electrons accelerated to about the speed of light in an 844 meter long circular tube. A handy comparison: “If I were to use medical X-ray tomography to look at an Olympic village, I would be able to make out only the stadium. With the synchrotron based X-ray tomography, I would be able to distinguish individual blades of grass on the field..”

Diwaker hopes that conservators will be able to use the new insight to develop conservation strategies not just for paper artefacts but for combating biodegradation on a host of other types of cultural heritage materials. And that the developed methods can be extended to other studies related to soft matter.

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

Morphology and characterization of Dematiaceous fungi on a cellulose paper substrate using synchrotron X-ray microtomography, scanning electron microscopy and confocal laser scanning microscopy in the context of cultural heritage by H. M. Szczepanowska, D. Jha, and Th. G. Mathia. Anal. At. Spectrom. (Journal of Analystical Atomic Spetrometry), 2015,30, 651-657 DOI: 10.1039/C4JA00337C First published online 27 Nov 2014

This paper is behind a paywall. By the way, it is part of something the journal calls a themed collection:  Synchrotron radiation and neutrons in art and archaeology. Clicking on the ‘themed collection’ link will give you a view of the collection, i.e., titles, authors and brief abstracts.

World’s largest DNA origami: 200nm x 300nm

If the 200nm x 300nm size is the world’s largest DNA origami, what is the standard size?  Before you get the answer to that question, here’s more about the world’s largest from a Sept. 11, 2014 news item on Nanowerk,

Researchers from North Carolina State University, Duke University and the University of Copenhagen have created the world’s largest DNA origami, which are nanoscale constructions with applications ranging from biomedical research to nanoelectronics.

“These origami can be customized for use in everything from studying cell behavior to creating templates for the nanofabrication of electronic components,” says Dr. Thom LaBean, an associate professor of materials science and engineering at NC State and senior author of a paper describing the work …

A Sept. ?, 2014 North Carolina State University (NCSU) news release, which originated the news item, describes DNA origami and the process for creating it,

DNA origami are self-assembling biochemical structures that are made up of two types of DNA. To make DNA origami, researchers begin with a biologically derived strand of DNA called the scaffold strand. The researchers then design customized synthetic strands of DNA, called staple strands. Each staple strand is made up of a specific sequence of bases (adenine, cytosine, thaline and guanine – the building blocks of DNA), which is designed to pair with specific subsequences on the scaffold strand.

The staple strands are introduced into a solution containing the scaffold strand, and the solution is then heated and cooled. During this process, each staple strand attaches to specific sections of the scaffold strand, pulling those sections together and folding the scaffold strand into a specific shape.

Here’s the answer to the question I asked earlier about the standard size for DNA origami and a description for how the researchers approached the problem of making a bigger piece (from the news release,

The standard for DNA origami has long been limited to a scaffold strand that is made up of 7,249 bases, creating structures that measure roughly 70 nanometers (nm) by 90 nm, though the shapes may vary.

However, the research team led by LaBean has now created DNA origami consisting of 51,466 bases, measuring approximately 200 nm by 300 nm.

“We had to do two things to make this viable,” says Dr. Alexandria Marchi, lead author of the paper and a postdoctoral researcher at Duke. “First we had to develop a custom scaffold strand that contained 51 kilobases. We did that with the help of molecular biologist Stanley Brown at the University of Copenhagen.

“Second, in order to make this economically feasible, we had to find a cost-effective way of synthesizing staple strands – because we went from needing 220 staple strands to needing more than 1,600,” Marchi says.

The researchers did this by using what is essentially a converted inkjet printer to synthesize DNA directly onto a plastic chip.

“The technique we used not only creates large DNA origami, but has a fairly uniform output,” LaBean says. “More than 90 percent of the origami are self-assembling properly.”

For the curious, a link to and a citation for the paper,

Toward Larger DNA Origami by Alexandria N. Marchi, *Ishtiaq Saaem*, Briana N. Vogen, Stanley Brown, and Thomas H. LaBean. Nano Lett., Article ASAP DOI: 10.1021/nl502626s Publication Date (Web): September 1, 2014
Copyright © 2014 American Chemical Society

This paper is behind a paywall.

*May 10, 2021 According to a comment on my ‘About’ page, Dr. Saaem has pled guilty to obstruction of justice in a case concerning ricin (a deadly toxin). You can read a full account of Saaem’s pleading in an April 13, 2021 US Attorney’s Office, District of Massachusetts release,

According to court records, Saaem held a Ph.D. in biomedical engineering, resided in Massachusetts and worked as the director of advanced research at a biotechnology firm based in Massachusetts. Saaem became interested in acquiring ricin from castor beans as well as convallatoxin, a poison found in lily of the valley plants, after watching “Breaking Bad,” a popular television show. Saaem ordered online 100 packets of castor beans, each containing eight seeds. Saaem falsely told law enforcement agents that he purchased castor beans for planting at his apartment for decoration and that he had accidentally purchased 100 packets instead of one. After he spoke to agents, Saaem researched tasteless poisons that could be made at home.

The charge of obstruction of justice provides for a sentence of up to 20 years in prison, three years of supervised release and a fine of up to $250,000. Sentences are imposed by a federal district court judge based upon the Sentencing Guidelines and other statutory factors.

 

According to news reports, Dr. Saaem will be sentenced in August 2021.

The Danes get more from their marijuana

A Sept. 8, 2014 news item on ScienceDaily features work at the University of Copenhagen where scientists are researching a new method for reducing consumption of drugs such as adrenaline and cannabis when used therapeutically,

About 40% of all medicines used today work through the so-called “G protein-coupled receptors.” These receptors react to changes in the cell environment, for example, to increased amounts of chemicals like cannabis, adrenaline or the medications we take and are therefore of paramount importance to the pharmaceutical industry.

“There is a lot of attention on research into “G protein-coupled receptors,” because they have a key roll in recognizing and binding different substances. Our new method is of interest to the industry because it can contribute to faster and cheaper drug development,” explains Professor Dimitrios Stamou, who heads the Nanomedicine research group at the Nano-Science Center, where the method has been developed. …

A Sept. 8, 2014 University of Copenhagen news release on EurekAlert, which originated the news item, provides a little more detail,

The new method will reduce dramatically the use of precious membrane protein samples. Traditionally, you test a medicinal substance by using small drops of a sample containing the protein that the medicine binds to. If you look closely enough however, each drop is composed of thousands of billions of small nano-containers containing the isolated proteins. Until now, it has been assumed that all of these nano-containers are identical. But it turns out this is not the case and that is why researchers can use a billion times smaller samples for testing drug candidates than hitherto.

“We have discovered that each one of the countless nano-containers is unique. Our method allows us to collect information about each individual nano-container. We can use this information to construct high-throughput screens, where you can, for example, test how medicinal drugs bind G protein-coupled receptors”, explains Signe Mathiasen, who is first author of the paper describing the screening method in Nature Methods. Signe Mathiasen has worked on developing a screening method over the last four years at the University of Copenhagen, where she wrote her PhD thesis research project under the supervision of Professor Stamou.

Although the title doesn’t betray its marijuana orientation, this is a link to and a citation for the researchers’ work,

Nanoscale high-content analysis using compositional heterogeneities of single proteoliposomes by Signe Mathiasen, Sune M Christensen, Juan José Fung, Søren G F Rasmussen, Jonathan F Fay, Sune K Jorgensen, Salome Veshaguri, David L Farrens, Maria Kiskowski, Brian Kobilka, & Dimitrios Stamou. Nature Methods 11, 931–934 (2014) doi:10.1038/nmeth.3062 Published online 03 August 2014

This paper is behind a paywall.