Tag Archives: Germany

Light-based computation made better with silver

It’s pretty amazing to imagine a future where computers run on light but according to a May 16, 2017 news item on ScienceDaily the idea is not beyond the realms of possibility,

Tomorrow’s computers will run on light, and gold nanoparticle chains show much promise as light conductors. Now Ludwig-Maximilians-Universitaet (LMU) in Munich scientists have demonstrated how tiny spots of silver could markedly reduce energy consumption in light-based computation.

Today’s computers are faster and smaller than ever before. The latest generation of transistors will have structural features with dimensions of only 10 nanometers. If computers are to become even faster and at the same time more energy efficient at these minuscule scales, they will probably need to process information using light particles instead of electrons. This is referred to as “optical computing.”

The silver serves as a kind of intermediary between the gold particles while not dissipating energy. Capture: Liedl/Hohmann (NIM)

A March 15, 2017 LMU press release (also one EurekAlert), which originated the news item, describes a current use of light in telecommunications technology and this latest research breakthrough (the discrepancy in dates is likely due to when the paper was made available online versus in print),

Fiber-optic networks already use light to transport data over long distances at high speed and with minimum loss. The diameters of the thinnest cables, however, are in the micrometer range, as the light waves — with a wavelength of around one micrometer — must be able to oscillate unhindered. In order to process data on a micro- or even nanochip, an entirely new system is therefore required.

One possibility would be to conduct light signals via so-called plasmon oscillations. This involves a light particle (photon) exciting the electron cloud of a gold nanoparticle so that it starts oscillating. These waves then travel along a chain of nanoparticles at approximately 10% of the speed of light. This approach achieves two goals: nanometer-scale dimensions and enormous speed. What remains, however, is the energy consumption. In a chain composed purely of gold, this would be almost as high as in conventional transistors, due to the considerable heat development in the gold particles.

A tiny spot of silver

Tim Liedl, Professor of Physics at LMU and PI at the cluster of excellence Nanosystems Initiative Munich (NIM), together with colleagues from Ohio University, has now published an article in the journal Nature Physics, which describes how silver nanoparticles can significantly reduce the energy consumption. The physicists built a sort of miniature test track with a length of around 100 nanometers, composed of three nanoparticles: one gold nanoparticle at each end, with a silver nanoparticle right in the middle.

The silver serves as a kind of intermediary between the gold particles while not dissipating energy. To make the silver particle’s plasmon oscillate, more excitation energy is required than for gold. Therefore, the energy just flows “around” the silver particle. “Transport is mediated via the coupling of the electromagnetic fields around the so-called hot spots which are created between each of the two gold particles and the silver particle,” explains Tim Liedl. “This allows the energy to be transported with almost no loss, and on a femtosecond time scale.”

Textbook quantum model

The decisive precondition for the experiments was the fact that Tim Liedl and his colleagues are experts in the exquisitely exact placement of nanostructures. This is done by the DNA origami method, which allows different crystalline nanoparticles to be placed at precisely defined nanodistances from each other. Similar experiments had previously been conducted using conventional lithography techniques. However, these do not provide the required spatial precision, in particular where different types of metals are involved.

In parallel, the physicists simulated the experimental set-up on the computer – and had their results confirmed. In addition to classical electrodynamic simulations, Alexander Govorov, Professor of Physics at Ohio University, Athens, USA, was able to establish a simple quantum-mechanical model: “In this model, the classical and the quantum-mechanical pictures match very well, which makes it a potential example for the textbooks.”

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

Hotspot-mediated non-dissipative and ultrafast plasmon passage by Eva-Maria Roller, Lucas V. Besteiro, Claudia Pupp, Larousse Khosravi Khorashad, Alexander O. Govorov, & Tim Liedl. Nature Physics (2017) doi:10.1038/nphys4120 Published online 15 May 2017

This paper is behind a paywall.

Material that sheds like a snake when it’s damaged

Truly water-repellent materials are on the horizon. Or, they would be if one tiny problem was solved. According to a May  3, 2017 news item on ScienceDaily, scientists may have come up with that solution,

Imagine a raincoat that heals a scratch by shedding the part of the outer layer that’s damaged. To create such a material, scientists have turned to nature for inspiration. They report in ACS’ journal Langmuir a water-repellant material that molts like a snake’s skin when damaged to reveal another hydrophobic [water-repellent] layer beneath it.

A May 3, 2017 American Chemical Society (ACS) press release (also on EurekAlert), which originated the news item, expands on the theme,

Lotus leaves, water striders and other superhydrophobic examples from nature have inspired scientists to copy their water-repelling architecture to develop new materials. Such materials are often made by coating a substrate with nanostructures, which can be shored up by adding microstructures to the mix. Superhydrophobic surfaces could be useful in a range of applications including rain gear, medical instruments and self-cleaning car windows. But most of the prototypes so far haven’t been strong enough to stand up to damage by sharp objects. To address this shortcoming, Jürgen Rühe and colleagues again found a potential solution in nature — in snake and lizard skins.

The researchers stacked three layers to create their material: a water-repellant film made with poly-1H,1H,2H,2H-perfluorodecyl acrylate (PFA) “nanograss” on the top, a water-soluble polymer in the middle and a superhydrophobic silicon nanograss film on the bottom. Nanograss consists of tiny needle-like projections sticking straight up. The team scratched the coating and submerged the material in water, which then seeped into the cut and dissolved the polymer. The top layer then peeled off like molted skin and floated away, exposing the bottom, water-repellant film. Although further work is needed to strengthen the top coating so that a scratch won’t be able to penetrate all three layers, the researchers say it offers a new approach to creating self-cleaning and water-repellant materials.

The authors acknowledge support from the German Federal Ministry of Education and Research (BMBF) and VDI/VDE/IT GmbH through project NanoTau.

Here’s a video demonstrating the concept,

Published on May 2, 2017

Scientists turn to snakes and lizards for inspiration to create a new material that sheds its outer layer when scratched.

Finally, a link to and a citation for the paper,

Molting Materials: Restoring Superhydrophobicity after Severe Damage via Snakeskin-like Shedding by Roland Hönes, Vitaliy Kondrashov, and Jürgen Rühe. Langmuir, Article ASAP DOI: 10.1021/acs.langmuir.7b00814 Publication Date (Web): April 14, 2017

Copyright © 2017 American Chemical Society

This paper is behind a paywall.

Canada and its Vancouver tech scene gets a boost

Prime Minister Justin Trudeau has been running around attending tech events both in the Vancouver area (Canada) and in Seattle these last few days (May 17 and May 18, 2017). First he attended the Microsoft CEO Summit as noted in a May 11, 2017 news release from the Prime Minister’s Office (Note: I have a few comments about this performance and the Canadian tech scene at the end of this post),

The Prime Minister, Justin Trudeau, today [May 11, 2017] announced that he will participate in the Microsoft CEO Summit in Seattle, Washington, on May 17 and 18 [2017], to promote the Cascadia Innovation Corridor, encourage investment in the Canadian technology sector, and draw global talent to Canada.

This year’s summit, under the theme “The CEO Agenda: Navigating Change,” will bring together more than 150 chief executive officers. While at the Summit, Prime Minister Trudeau will showcase Budget 2017’s Innovation and Skills Plan and demonstrate how Canada is making it easier for Canadian entrepreneurs and innovators to turn their ideas into thriving businesses.

Prime Minister Trudeau will also meet with Washington Governor Jay Inslee.


“Canada’s greatest strength is its skilled, hard-working, creative, and diverse workforce. Canada is recognized as a world leader in research and development in many areas like artificial intelligence, quantum computing, and 3D programming. Our government will continue to help Canadian businesses grow and create good, well-paying middle class jobs in today’s high-tech economy.”
— Rt. Honourable Justin Trudeau, Prime Minister of Canada

Quick Facts

  • Canada-U.S. bilateral trade in goods and services reached approximately $882 billion in 2016.
  • Nearly 400,000 people and over $2 billion-worth of goods and services cross the Canada-U.S. border every day.
  • Canada-Washington bilateral trade was $19.8 billion in 2016. Some 223,300 jobs in the State of Washington depend on trade and investment with Canada. Canada is among Washington’s top export destinations.

Associated Link

Here’s a little more about the Microsoft meeting from a May 17, 2017 article by Alan Boyle for GeekWire.com (Note: Links have been removed),

So far, this year’s Microsoft CEO Summit has been all about Canadian Prime Minister Justin Trudeau’s talk today, but there’s been precious little information available about who else is attending – and Trudeau may be one of the big reasons why.

Microsoft co-founder Bill Gates created the annual summit back in 1997, to give global business leaders an opportunity to share their experiences and learn about new technologies that will have an impact on business in the future. The event’s attendee list is kept largely confidential, as is the substance of the discussions.

This year, Microsoft says the summit’s two themes are “trust in technology” (as in cybersecurity, international hacking, privacy and the flow of data) and “the race to space” (as in privately funded space efforts such as Amazon billionaire Jeff Bezos’ Blue Origin rocket venture).

Usually, Microsoft lists a few folks who are attending the summit on the company’s Redmond campus, just to give a sense of the event’s cachet. For example, last year’s headliners included Berkshire Hathaway CEO Warren Buffett and Exxon Mobil CEO Rex Tillerson (who is now the Trump administration’s secretary of state)

This year, however, the spotlight has fallen almost exclusively on the hunky 45-year-old Trudeau, the first sitting head of government or state to address the summit. Microsoft isn’t saying anything about the other 140-plus VIPs attending the discussions. “Out of respect for the privacy of our guests, we are not providing any additional information,” a Microsoft spokesperson told GeekWire via email.

Even Trudeau’s remarks at the summit are hush-hush, although officials say he’s talking up Canada’s tech sector.  …

Laura Kane’s May 18, 2017 article for therecord.com provides a little more information about Trudeau’s May 18, 2017 activities in Washington state,

Prime Minister Justin Trudeau continued his efforts to promote Canada’s technology sector to officials in Washington state on Thursday [May 18, 2017], meeting with Gov. Jay Inslee a day after attending the secretive Microsoft CEO Summit.

Trudeau and Inslee discussed, among other issues, the development of the Cascadia Innovation Corridor, an initiative that aims to strengthen technology industry ties between British Columbia and Washington.

The pair also spoke about trade and investment opportunities and innovation in the energy sector, said Trudeau’s office. In brief remarks before the meeting, the prime minister said Washington and Canada share a lot in common.

But protesters clad in yellow hazardous material suits that read “Keystone XL Toxic Cleanup Crew” gathered outside the hotel to criticize Trudeau’s environmental record, arguing his support of pipelines is at odds with any global warming promises he has made.

Later that afternoon, Trudeau visited Electronic Arts (a US games company with offices in the Vancouver area) for more tech talk as Stephanie Ip notes in her May 18, 2017 article for The Vancouver Sun,

Prime Minister Justin Trudeau was in Metro Vancouver Thursday [may 18, 2017] to learn from local tech and business leaders how the federal government can boost B.C.’s tech sector.

The roundtable discussion was organized by the Vancouver Economic Commission and hosted in Burnaby at Electronic Arts’ Capture Lab, where the video game company behind the popular FIFA, Madden and NHL franchises records human movement to add more realism to its digital characters. Representatives from Amazon, Launch Academy, Sony Pictures, Darkhorse 101 Pictures and Front Fundr were also there.

While the roundtable was not open to media, Trudeau met beforehand with media.

“We’re going to talk about how the government can be a better partner or better get out of your way in some cases to allow you to continue to grow, to succeed, to create great opportunities to allow innovation to advance success in Canada and to create good jobs for Canadians and draw in people from around the world and continue to lead the way in the world,” he said.

“Everything from clean tech, to bio-medical advances, to innovation in digital economy — there’s a lot of very, very exciting things going on”

Comments on the US tech sector and the supposed Canadian tech sector

I wonder at all the secrecy. As for the companies mentioned as being at the roundtable, you’ll notice a preponderance of US companies with Launch Academy and Front Fundr (which is not a tech company but a crowdfunding equity company) supplying Canadian content. As for Darkhorse 101 Pictures,  I strongly suspect (after an online search) it is part of Darkhorse Comics (as US company) which has an entertainment division.

Perhaps it didn’t seem worthwhile to mention the Canadian companies? In that case, that’s a sad reflection on how poorly we and our media support our tech sector.

In fact, it seems Trudeau’s version of the Canadian technology sector is for us to continue in our role as a branch plant remaining forever in service of the US economy or at least the US tech sector which may be experiencing some concerns with the US Trump administration and what appears to be an increasingly isolationist perspective with regard to trade and immigration. It’s a perspective that the tech sector, especially the entertainment component, can ill afford.

As for the Cascadia Innovation Corridor mentioned in the Prime Minister’s news release and in Kane’s article, I have more about that in a Feb. 28, 2017 posting about the Cascadia Data Analytics Cooperative.

I noticed he mentioned clean tech as an area of excitement. Well, we just lost a significant player not to the US this time but to the EU (European Union) or more specifically, Germany. (There’ll be more about that in an upcoming post.)

I’m glad to see that Trudeau remains interested in Canadian science and technology but perhaps he could concentrate on new ways of promoting sectoral health rather than relying on the same old thing.

Ultra-thin superconducting film for outer space

Truth in a press release? But first, there’s this April 6, 2017 news item on Nanowerk announcing research that may have applications in aerospace and other sectors,

Experimental physicists in the research group led by Professor Uwe Hartmann at Saarland University have developed a thin nanomaterial with superconducting properties. Below about -200 °C these materials conduct electricity without loss, levitate magnets and can screen magnetic fields.

The particularly interesting aspect of this work is that the research team has succeeded in creating superconducting nanowires that can be woven into an ultra-thin film that is as flexible as cling film. As a result, novel coatings for applications ranging from aerospace to medical technology are becoming possible.

The research team will be exhibiting their superconducting film at Hannover Messe from April 24th to April 28th [2017] (Hall 2, Stand B46) and are looking for commercial and industrial partners with whom they can develop their system for practical applications.

An April 6, 2017 University of Saarland press release (also on EurekAlert), which originated the news item, provides more details along with a line that rings with the truth,

A team of experimental physicists at Saarland University have developed something that – it has to be said – seems pretty unremarkable at first sight. [emphasis mine] It looks like nothing more than a charred black piece of paper. But appearances can be deceiving. This unassuming object is a superconductor. The term ‘superconductor’ is given to a material that (usually at a very low temperatures) has zero electrical resistance and can therefore conduct an electric current without loss. Put simply, the electrons in the material can flow unrestricted through the cold immobilized atomic lattice. In the absence of electrical resistance, if a magnet is brought up close to a cold superconductor, the magnet effectively ‘sees’ a mirror image of itself in the superconducting material. So if a superconductor and a magnet are placed in close proximity to one another and cooled with liquid nitrogen they will repel each another and the magnet levitates above the superconductor. The term ‘levitation’ comes from the Latin word levitas meaning lightness. It’s a bit like a low-temperature version of the hoverboard from the ‘Back to the Future’ films. If the temperature is too high, however, frictionless sliding is just not going to happen.
Many of the common superconducting materials available today are rigid, brittle and dense, which makes them heavy. The Saarbrücken physicists have now succeeded in packing superconducting properties into a thin flexible film. The material is a essentially a woven fabric of plastic fibres and high-temperature superconducting nanowires. ‘That makes the material very pliable and adaptable – like cling film (or ‘plastic wrap’ as it’s also known). Theoretically, the material can be made to any size. And we need fewer resources than are typically required to make superconducting ceramics, so our superconducting mesh is also cheaper to fabricate,’ explains Uwe Hartmann, Professor of Nanostructure Research and Nanotechnology at Saarland University.

The low weight of the film is particularly advantageous. ‘With a density of only 0.05 grams per cubic centimetre, the material is very light, weighing about a hundred times less than a conventional superconductor. This makes the material very promising for all those applications where weight is an issue, such as in space technology. There are also potential applications in medical technology,’ explains Hartmann. The material could be used as a novel coating to provide low-temperature screening from electromagnetic fields, or it could be used in flexible cables or to facilitate friction-free motion.

In order to be able to weave this new material, the experimental physicists made use of a technique known as electrospinning, which is usually used in the manufacture of polymeric fibres. ‘We force a liquid material through a very fine nozzle known as a spinneret to which a high electrical voltage has been applied. This produces nanowire filaments that are a thousand times thinner than the diameter of a human hair, typically about 300 nanometres or less. We then heat the mesh of fibres so that superconductors of the right composition are created. The superconducting material itself is typically an yttrium-barium-copper-oxide or similar compound,’ explains Dr. Michael Koblischka, one of the research scientists in Hartmann‘s group.

The research project received €100,000 in funding from the Volkswagen Foundation as part of its ‘Experiment!’ initiative. The initiative aims to encourage curiosity-driven, blue-skies research. The positive results from the Saarbrücken research team demonstrate the value of this type of funding. Since September 2016, the project has been supported by the German Research Foundation (DFG). Total funds of around €425,000 will be provided over a three-year period during which the research team will be carrying out more detailed investigations into the properties of the nanowires.

I’d say the “unremarkable but appearances can be deceiving” comments are true more often than not. I think that’s one of the hard things about science. Big advances can look nondescript.

What looks like a pretty unremarkable piece of burnt paper is in fact an ultrathin superconductor that has been developed by the team lead by Uwe Hartmann (r.) shown here with doctoral student XianLin Zeng. Courtesy: Saarland University

In any event, here’s a link to and a citation for the paper,

Preparation of granular Bi-2212 nanowires by electrospinning by Xian Lin Zeng, Michael R Koblischka, Thomas Karwoth, Thomas Hauet, and Uwe Hartmann. Superconductor Science and Technology, Volume 30, Number 3 Published 1 February 2017

© 2017 IOP Publishing Ltd

This paper is behind a paywall.

Nanocar Race winners!

In fact, there was a tie although it seems the Swiss winners were a little more excited. A May 1, 2017 news item on swissinfo.ch provides fascinating detail,

“Swiss Nano Dragster”, driven by scientists from Basel, has won the first international car race involving molecular machines. The race involved four nano cars zipping round a pure gold racetrack measuring 100 nanometres – or one ten-thousandth of a millimetre.

The two Swiss pilots, Rémy Pawlak and Tobias Meier from the Swiss Nanoscience Institute and the Department of Physicsexternal link at the University of Basel, had to reach the chequered flag – negotiating two curves en route – within 38 hours. [emphasis mine*]

The winning drivers, who actually shared first place with a US-Austrian team, were not sitting behind a steering wheel but in front of a computer. They used this to propel their single-molecule vehicle with a small electric shock from a scanning tunnelling microscope.

During such a race, a tunnelling current flows between the tip of the microscope and the molecule, with the size of the current depending on the distance between molecule and tip. If the current is high enough, the molecule starts to move and can be steered over the racetrack, a bit like a hovercraft.


The race track was maintained at a very low temperature (-268 degrees Celsius) so that the molecules didn’t move without the current.

What’s more, any nudging of the molecule by the microscope tip would have led to disqualification.

Miniature motors

The race, held in Toulouse, France, and organised by the National Centre for Scientific Research (CNRS), was originally going to be held in October 2016, but problems with some cars resulted in a slight delay. In the end, organisers selected four of nine applicants since there were only four racetracks.

The cars measured between one and three nanometres – about 30,000 times smaller than a human hair. The Swiss Nano Dragster is, in technical language, a 4′-(4-Tolyl)-2,2′:6′,2”-terpyridine molecule.

The Swiss and US-Austrian teams outraced rivals from the US and Germany.

The race is not just a bit of fun for scientists. The researchers hope to gain insights into how molecules move.

I believe this Basel University .gif is from the race,

*Emphasis added on May 9, 2017 at 12:26 pm PT. See my May 9, 2017 posting: Nanocar Race winners: The US-Austrian team for the other half of this story.

Graphene-based neural probes

I have two news bits (dated almost one month apart) about the use of graphene in neural probes, one from the European Union and the other from Korea.

European Union (EU)

This work is being announced by the European Commission’s (a subset of the EU) Graphene Flagship (one of two mega-funding projects announced in 2013; 1B Euros each over ten years for the Graphene Flagship and the Human Brain Project).

According to a March 27, 2017 news item on ScienceDaily, researchers have developed a graphene-based neural probe that has been tested on rats,

Measuring brain activity with precision is essential to developing further understanding of diseases such as epilepsy and disorders that affect brain function and motor control. Neural probes with high spatial resolution are needed for both recording and stimulating specific functional areas of the brain. Now, researchers from the Graphene Flagship have developed a new device for recording brain activity in high resolution while maintaining excellent signal to noise ratio (SNR). Based on graphene field-effect transistors, the flexible devices open up new possibilities for the development of functional implants and interfaces.

The research, published in 2D Materials, was a collaborative effort involving Flagship partners Technical University of Munich (TU Munich; Germany), Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS; Spain), Spanish National Research Council (CSIC; Spain), The Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN; Spain) and the Catalan Institute of Nanoscience and Nanotechnology (ICN2; Spain).

Caption: Graphene transistors integrated in a flexible neural probe enables electrical signals from neurons to be measured with high accuracy and density. Inset: The tip of the probe contains 16 flexible graphene transistors. Credit: ICN2

A March 27, 2017 Graphene Flagship press release on EurekAlert, which originated the news item, describes the work,  in more detail,

The devices were used to record the large signals generated by pre-epileptic activity in rats, as well as the smaller levels of brain activity during sleep and in response to visual light stimulation. These types of activities lead to much smaller electrical signals, and are at the level of typical brain activity. Neural activity is detected through the highly localised electric fields generated when neurons fire, so densely packed, ultra-small measuring devices is important for accurate brain readings.

The neural probes are placed directly on the surface of the brain, so safety is of paramount importance for the development of graphene-based neural implant devices. Importantly, the researchers determined that the graphene-based probes are non-toxic, and did not induce any significant inflammation.

Devices implanted in the brain as neural prosthesis for therapeutic brain stimulation technologies and interfaces for sensory and motor devices, such as artificial limbs, are an important goal for improving quality of life for patients. This work represents a first step towards the use of graphene in research as well as clinical neural devices, showing that graphene-based technologies can deliver the high resolution and high SNR needed for these applications.

First author Benno Blaschke (TU Munich) said “Graphene is one of the few materials that allows recording in a transistor configuration and simultaneously complies with all other requirements for neural probes such as flexibility, biocompability and chemical stability. Although graphene is ideally suited for flexible electronics, it was a great challenge to transfer our fabrication process from rigid substrates to flexible ones. The next step is to optimize the wafer-scale fabrication process and improve device flexibility and stability.”

Jose Antonio Garrido (ICN2), led the research. He said “Mechanical compliance is an important requirement for safe neural probes and interfaces. Currently, the focus is on ultra-soft materials that can adapt conformally to the brain surface. Graphene neural interfaces have shown already great potential, but we have to improve on the yield and homogeneity of the device production in order to advance towards a real technology. Once we have demonstrated the proof of concept in animal studies, the next goal will be to work towards the first human clinical trial with graphene devices during intraoperative mapping of the brain. This means addressing all regulatory issues associated to medical devices such as safety, biocompatibility, etc.”

Caption: The graphene-based neural probes were used to detect rats’ responses to visual stimulation, as well as neural signals during sleep. Both types of signals are small, and typically difficult to measure. Credit: ICN2

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

Mapping brain activity with flexible graphene micro-transistors by Benno M Blaschke, Núria Tort-Colet, Anton Guimerà-Brunet, Julia Weinert, Lionel Rousseau, Axel Heimann, Simon Drieschner, Oliver Kempski, Rosa Villa, Maria V Sanchez-Vives. 2D Materials, Volume 4, Number 2 DOI https://doi.org/10.1088/2053-1583/aa5eff Published 24 February 2017

© 2017 IOP Publishing Ltd

This paper is behind a paywall.


While this research from Korea was published more recently, the probe itself has not been subjected to in vivo (animal testing). From an April 19, 2017 news item on ScienceDaily,

Electrodes placed in the brain record neural activity, and can help treat neural diseases like Parkinson’s and epilepsy. Interest is also growing in developing better brain-machine interfaces, in which electrodes can help control prosthetic limbs. Progress in these fields is hindered by limitations in electrodes, which are relatively stiff and can damage soft brain tissue.

Designing smaller, gentler electrodes that still pick up brain signals is a challenge because brain signals are so weak. Typically, the smaller the electrode, the harder it is to detect a signal. However, a team from the Daegu Gyeongbuk Institute of Science & Technology [DGIST} in Korea developed new probes that are small, flexible and read brain signals clearly.

This is a pretty interesting way to illustrate the research,

Caption: Graphene and gold make a better brain probe. Credit: DGIST

An April 19, 2017 DGIST press release (also on EurekAlert), which originated the news item, expands on the theme (Note: A link has been removed),

The probe consists of an electrode, which records the brain signal. The signal travels down an interconnection line to a connector, which transfers the signal to machines measuring and analysing the signals.

The electrode starts with a thin gold base. Attached to the base are tiny zinc oxide nanowires, which are coated in a thin layer of gold, and then a layer of conducting polymer called PEDOT. These combined materials increase the probe’s effective surface area, conducting properties, and strength of the electrode, while still maintaining flexibility and compatibility with soft tissue.

Packing several long, thin nanowires together onto one probe enables the scientists to make a smaller electrode that retains the same effective surface area of a larger, flat electrode. This means the electrode can shrink, but not reduce signal detection. The interconnection line is made of a mix of graphene and gold. Graphene is flexible and gold is an excellent conductor. The researchers tested the probe and found it read rat brain signals very clearly, much better than a standard flat, gold electrode.

“Our graphene and nanowires-based flexible electrode array can be useful for monitoring and recording the functions of the nervous system, or to deliver electrical signals to the brain,” the researchers conclude in their paper recently published in the journal ACS Applied Materials and Interfaces.

The probe requires further clinical tests before widespread commercialization. The researchers are also interested in developing a wireless version to make it more convenient for a variety of applications.

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

Enhancement of Interface Characteristics of Neural Probe Based on Graphene, ZnO Nanowires, and Conducting Polymer PEDOT by Mingyu Ryu, Jae Hoon Yang, Yumi Ahn, Minkyung Sim, Kyung Hwa Lee, Kyungsoo Kim, Taeju Lee, Seung-Jun Yoo, So Yeun Kim, Cheil Moon, Minkyu Je, Ji-Woong Choi, Youngu Lee, and Jae Eun Jang. ACS Appl. Mater. Interfaces, 2017, 9 (12), pp 10577–10586 DOI: 10.1021/acsami.7b02975 Publication Date (Web): March 7, 2017

Copyright © 2017 American Chemical Society

This paper is behind a paywall.

Nanomedicine and an enhanced uptake of nanoparticles

It’s nice to know that a step forward has been taken with regard to improving uptake in  nanoparticle-based drug delivery (see my April 27, 2016 posting titled: How many nanoparticle-based drugs does it take to kill a cancer tumour? More than 1% for insight into the difficulties of f nanoparticle-based drug delivery systems).

Here’s the latest move forward in a March 8, 2017 news item on Nanowerk (Note: A link has been removed),

Nanotechnology has become a growing part of medical research in recent years, with scientists feverishly working to see if tiny particles could revolutionize the world of drug delivery.

But many questions remain about how to effectively transport those particles and associated drugs to cells.
In an article published today in Scientific Reports (“Enhanced cellular uptake of size-separated lipophilic silicon nanoparticles”), FSU Associate Professor of Biological Science Steven Lenhert takes a step forward in the understanding of nanoparticles and how they can best be used to deliver drugs.

After conducting a series of experiments, Lenhert and his colleagues found that it may be possible to boost the efficacy of medicine entering target cells via a nanoparticle.

A March 8, 2017 Florida State University news release by Kathleen Haughney, which originated the news item, provides more detail about the research (an international collaboration involving the University of Toronto [Canada] and the Karlsruhe Institute of Technology [Germany]),

“We can enhance how cells take them up and make more drugs more potent,” Lenhert said.

Initially, Lenhert and his colleagues from the University of Toronto and the Karlsruhe Institute of Technology  wanted to see what happened when they encapsulated silicon nanoparticles in liposomes — or small spherical sacs of molecules — and delivered them to HeLa cells, a standard cancer cell model.

The initial goal was to test the toxicity of silicon-based nanoparticles and get a better understanding of its biological activity.

Silicon is a non-toxic substance and has well-known optical properties that allow their nanostructures to appear fluorescent under an infrared camera, where tissue would be nearly transparent. Scientists believe it has enormous potential as a delivery agent for drugs as well as in medical imaging.

But there are still questions about how silicon behaves at such a small size.

“Nanoparticles change properties as they get smaller, so scientists want to understand the biological activity,” Lenhert said. “For example, how does shape and size affect toxicity?”

Scientists found that 10 out of 18 types of the particles, ranging from 1.5 nanometers to 6 nanometers, were significantly more toxic than crude mixtures of the material.

At first, scientists believed this could be a setback, but they then discovered the reason for the toxicity levels. The more toxic fragments also had enhanced cellular uptake.

That information is more valuable long term, Lenhert said, because it means they could potentially alter nanoparticles to enhance the potency of a given therapeutic.

The work also paves the way for researchers to screen libraries of nanoparticles to see how cells react.

“This is an essential step toward the discovery of novel nanotechnology based therapeutics,” Lenhert said. “There’s big potential here for new therapeutics, but we need to be able to test everything first.”

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

Enhanced cellular uptake of size-separated lipophilic silicon nanoparticles by Aubrey E. Kusi-Appiah, Melanie L. Mastronardi, Chenxi Qian, Kenneth K. Chen, Lida Ghazanfari, Plengchart Prommapan, Christian Kübel, Geoffrey A. Ozin, & Steven Lenhert. Scientific Reports 7, Article number: 43731 (2017) doi:10.1038/srep43731 Published online: 08 March 2017

This paper is open access.

New iron oxide nanoparticle as an MRI (magnetic resonance imaging) contrast agent

This high-resolution transmission electron micrograph of particles made by the research team shows the particles’ highly uniform size and shape. These are iron oxide particles just 3 nanometers across, coated with a zwitterion layer. Their small size means they can easily be cleared through the kidneys after injection. Courtesy of the researchers

A Feb. 14, 2017 news item on ScienceDaily announces a new MRI (magnetic resonance imaging) contrast agent,

A new, specially coated iron oxide nanoparticle developed by a team at MIT [Massachusetts Institute of Technology] and elsewhere could provide an alternative to conventional gadolinium-based contrast agents used for magnetic resonance imaging (MRI) procedures. In rare cases, the currently used gadolinium agents have been found to produce adverse effects in patients with impaired kidney function.

A Feb. 14, 2017 MIT news release (also on EurekAlert), which originated the news item, provides more technical detail,


The advent of MRI technology, which is used to observe details of specific organs or blood vessels, has been an enormous boon to medical diagnostics over the last few decades. About a third of the 60 million MRI procedures done annually worldwide use contrast-enhancing agents, mostly containing the element gadolinium. While these contrast agents have mostly proven safe over many years of use, some rare but significant side effects have shown up in a very small subset of patients. There may soon be a safer substitute thanks to this new research.

In place of gadolinium-based contrast agents, the researchers have found that they can produce similar MRI contrast with tiny nanoparticles of iron oxide that have been treated with a zwitterion coating. (Zwitterions are molecules that have areas of both positive and negative electrical charges, which cancel out to make them neutral overall.) The findings are being published this week in the Proceedings of the National Academy of Sciences, in a paper by Moungi Bawendi, the Lester Wolfe Professor of Chemistry at MIT; He Wei, an MIT postdoc; Oliver Bruns, an MIT research scientist; Michael Kaul at the University Medical Center Hamburg-Eppendorf in Germany; and 15 others.

Contrast agents, injected into the patient during an MRI procedure and designed to be quickly cleared from the body by the kidneys afterwards, are needed to make fine details of organ structures, blood vessels, and other specific tissues clearly visible in the images. Some agents produce dark areas in the resulting image, while others produce light areas. The primary agents for producing light areas contain gadolinium.

Iron oxide particles have been largely used as negative (dark) contrast agents, but radiologists vastly prefer positive (light) contrast agents such as gadolinium-based agents, as negative contrast can sometimes be difficult to distinguish from certain imaging artifacts and internal bleeding. But while the gadolinium-based agents have become the standard, evidence shows that in some very rare cases they can lead to an untreatable condition called nephrogenic systemic fibrosis, which can be fatal. In addition, evidence now shows that the gadolinium can build up in the brain, and although no effects of this buildup have yet been demonstrated, the FDA is investigating it for potential harm.

“Over the last decade, more and more side effects have come to light” from the gadolinium agents, Bruns says, so that led the research team to search for alternatives. “None of these issues exist for iron oxide,” at least none that have yet been detected, he says.

The key new finding by this team was to combine two existing techniques: making very tiny particles of iron oxide, and attaching certain molecules (called surface ligands) to the outsides of these particles to optimize their characteristics. The iron oxide inorganic core is small enough to produce a pronounced positive contrast in MRI, and the zwitterionic surface ligand, which was recently developed by Wei and coworkers in the Bawendi research group, makes the iron oxide particles water-soluble, compact, and biocompatible.

The combination of a very tiny iron oxide core and an ultrathin ligand shell leads to a total hydrodynamic diameter of 4.7 nanometers, below the 5.5-nanometer renal clearance threshold. This means that the coated iron oxide should quickly clear through the kidneys and not accumulate. This renal clearance property is an important feature where the particles perform comparably to gadolinium-based contrast agents.

Now that initial tests have demonstrated the particles’ effectiveness as contrast agents, Wei and Bruns say the next step will be to do further toxicology testing to show the particles’ safety, and to continue to improve the characteristics of the material. “It’s not perfect. We have more work to do,” Bruns says. But because iron oxide has been used for so long and in so many ways, even as an iron supplement, any negative effects could likely be treated by well-established protocols, the researchers say. If all goes well, the team is considering setting up a startup company to bring the material to production.

For some patients who are currently excluded from getting MRIs because of potential side effects of gadolinium, the new agents “could allow those patients to be eligible again” for the procedure, Bruns says. And, if it does turn out that the accumulation of gadolinium in the brain has negative effects, an overall phase-out of gadolinium for such uses could be needed. “If that turned out to be the case, this could potentially be a complete replacement,” he says.

Ralph Weissleder, a physician at Massachusetts General Hospital who was not involved in this work, says, “The work is of high interest, given the limitations of gadolinium-based contrast agents, which typically have short vascular half-lives and may be contraindicated in renally compromised patients.”

The research team included researchers in MIT’s chemistry, biological engineering, nuclear science and engineering, brain and cognitive sciences, and materials science and engineering departments and its program in Health Sciences and Technology; and at the University Medical Center Hamburg-Eppendorf; Brown University; and the Massachusetts General Hospital. It was supported by the MIT-Harvard NIH Center for Cancer Nanotechnology, the Army Research Office through MIT’s Institute for Soldier Nanotechnologies, the NIH-funded Laser Biomedical Research Center, the MIT Deshpande Center, and the European Union Seventh Framework Program.

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

Exceedingly small iron oxide nanoparticles as positive MRI contrast agents by He Wei, Oliver T. Bruns, Michael G. Kaul, Eric C. Hansen, Mariya Barch, Agata Wiśniowsk, Ou Chen, Yue Chen, Nan Li, Satoshi Okada, Jose M. Cordero, Markus Heine, Christian T. Farrar, Daniel M. Montana, Gerhard Adam, Harald Ittrich, Alan Jasanoff, Peter Nielsen, and Moungi G. Bawendi. PNAS February 13, 2017 doi: 10.1073/pnas.1620145114 Published online before print February 13, 2017

This paper is behind a paywall.

International Women’s Day March 8, 2017 and UNESCO/L’Oréal’s For Women in Science (Rising Talents)

Before getting to the science, here’s a little music in honour of March 8, 2017 International Women’s Day,

There is is a Wikipedia entry devoted to Rise Up (Parachute Club song), Note: Links have been removed<

“Rise Up” is a pop song recorded by the Canadian group Parachute Club on their self-titled 1983 album. It was produced and engineered by Daniel Lanois, and written by Parachute Club members Billy Bryans, Lauri Conger, Lorraine Segato and Steve Webster with lyrics contributed by filmmaker Lynne Fernie.

An upbeat call for peace, celebration, and “freedom / to love who we please,” the song was a national hit in Canada, and was hailed as a unique achievement in Canadian pop music:

“ Rarely does one experience a piece of music in white North America where the barrier between participant and observer breaks down. Rise Up rises right up and breaks down the wall.[1] ”

According to Segato, the song was not written with any one individual group in mind, but as a universal anthem of freedom and equality;[2] Fernie described the song’s lyrics as having been inspired in part by West Coast First Nations rituals in which young girls would “rise up” at dawn to adopt their adult names as a rite of passage.[3]

It remains the band’s most famous song, and has been adopted as an activist anthem for causes as diverse as gay rights, feminism, anti-racism and the New Democratic Party.[4] As well, the song’s reggae and soca-influenced rhythms made it the first significant commercial breakthrough for Caribbean music in Canada.

L’Oréal UNESCO For Women in Science

From a March 8, 2017 UNESCO press release (received via email),

Fifteen outstanding young women researchers, selected
among more than 250 candidates in the framework of the 19th edition of
the L’Oréal-UNESCO For Women in Science awards, will receive the
International Rising Talent fellowship during a gala on 21 March at the
hotel Pullman Tour Eiffel de Paris. By recognizing their achievements at
a key moment in their careers, the _For Women in Science programme aims
to help them pursue their research.

Since 1998, the L’Oréal-UNESCO _For Women in Science programme [1]
has highlighted the achievements of outstanding women scientists and
supported promising younger women who are in the early stages of their
scientific careers. Selected among the best national and regional
L’Oréal-UNESCO fellows, the International Rising Talents come from
all regions of the world (Africa and Arab States, Asia-Pacific, Europe,
Latin America and North America).

Together with the five laureates of the 2017 L’Oreal-UNESCO For Women
in Science awards [2], they will participate in a week of events,
training and exchanges that will culminate with the award ceremony on 23
March 2017 at the Mutualité in Paris.

The 2017 International Rising Talent are recognized for their work in
the following five categories:


Fundamental medicine
In a coma: is the patient conscious or unconscious?     * ASSOCIATE

Clinical medicine
Recognizing Alzheimer’s before the first signs appear.


Biological Sciences
Neurodegenerative diseases: untangling aggregated proteins.
* DOCTOR NAM-KYUNG YU, Republic of Korea
Biological Sciences
Rett syndrome: neuronal cells come under fire
Biological Sciences
Better understanding the immune system.
Biological Sciences
Better tissue healing.

Finding potential new sources of drugs

Biological Sciences
New antibiotics are right under our feet.
Biological Sciences
Unraveling the secrets of entangled proteins.


* MS NAZEK EL-ATAB, United Arab Emirates
Electrical, Electronic and Computer Engineering
Miniaturizing electronics without losing memory.
Piercing the secrets of cosmic radiation.
Material Sciences
Trapping radioactivity.
Unlocking the potential of energy resources with nanochemistry.


Biological Sciences
Predicting how animal biodiversity will evolve.
* DOCTOR SAM GILES, United Kingdom
Biological Sciences
Taking another look at the evolution of vertebrates thanks to their
Astronomy and Space Sciences
Looking at the birth of distant suns and planets to better understand
the solar system.

Congratulations to all of the winners!

You can find out more about these awards and others on the 2017 L’Oréal-UNESCO For Women in Science Awards webpage or on the For Women In Science website. (Again in honour of the 2017 International Women’s Day, I was the 92758th signer of the For Women in Science Manifesto.)

International Women’s Day origins

Thank you to Wikipedia (Note: Links have been removed),

International Women’s Day (IWD), originally called International Working Women’s Day, is celebrated on March 8 every year.[2] It commemorates the movement for women’s rights.

The earliest Women’s Day observance was held on February 28, 1909, in New York and organized by the Socialist Party of America.[3] On March 8, 1917, in the capital of the Russian Empire, Petrograd, a demonstration of women textile workers began, covering the whole city. This was the beginning of the Russian Revolution.[4] Seven days later, the Emperor of Russia Nicholas II abdicated and the provisional Government granted women the right to vote.[3] March 8 was declared a national holiday in Soviet Russia in 1917. The day was predominantly celebrated by the socialist movement and communist countries until it was adopted in 1975 by the United Nations.

It seems only fitting to bookend this post with another song (Happy International Women’s Day March 8, 2017),

While the lyrics are unabashedly romantic, the video is surprisingly moody with a bit of a ‘stalker vive’ although it does end up with her holding centre stage while singing and bouncing around in time to Walking on Sunshine.

Medieval chain mail inspires physicists

A Feb. 9, 2017 news item on Nanowerk describes new research at the Karlsruhe Institute of Technology (KIT), which takes its inspiration from medieval chain mail,

The Middle Ages certainly were far from being science-friendly: Whoever looked for new findings off the beaten track faced the threat of being burned at the stake. Hence, the contribution of this era to technical progress is deemed to be rather small. Scientists of Karlsruhe Institute of Technology (KIT), however, were inspired by medieval mail armor when producing a new metamaterial with novel properties. They succeeded in reversing the Hall coefficient of a material.

The Hall effect is the occurrence of a transverse electric voltage across an electric conductor passed by current flow, if this conductor is located in a magnetic field. This effect is a basic phenomenon of physics and allows to measure [sic] the strength of magnetic fields. It is the basis of magnetic speed sensors in cars or compasses in smartphones. Apart from measuring magnetic fields, the Hall effect can also be used to characterize metals and semiconductors and in particular to determine charge carrier density of the material. The sign of the measured Hall voltage allows conclusions to be drawn as to whether charge carriers in the semiconductor element carry positive or negative charge.

The ring structure of the metamaterial was inspired by mail armor of medieval knights. (Photo: KIT)

A Feb. ?, 2017 KIT press release (also on EurekAlert), which originated the news item, expands on the theme,

Mathematicians already predicted theoretically that it is possible to reverse the Hall coefficient of a material (such as gold or silicon), i.e. to reverse its sign. This was expected to be achieved by a three-dimensional ring structure resembling medieval mail armor. How-ever, this was considered difficult, as the ring mesh of millionths of a meter in size would have to be composed of three different components.


Die Ringstruktur des Metamaterials wurde von Kettenhemden aus der Ritterzeit inspiriert. (Bild: KIT)
The ring mesh of millionths of a meter in size. (Photo: KIT)

Christian Kern, Muamer Kadic, and Martin Wegener of KIT’s Institute of Applied Physics now found that a single basic material is sufficient, provided that the ring structure chosen follows a certain geometric arrangement. First, they produced polymer scaffolds with a highest-resolution 3D printer. Then, they coated these scaffolds with semiconducting zinc oxide.

The result of the experiment: The scientists can produce meta-materials with a positive coefficient, even though their components have negative coefficients. This sounds a bit like the philosopher’s stone, the formula, by means of which medieval alchemists tried to convert one substance into another. But here, no conversion takes place. “The charge carriers in the metamaterial remain negatively charged electrons,” Christian Kern explains. “Hall measurements only make them appear positively charged, as the structure forces them to take detours.”

Kern admits that this discovery so far is of no practical use. There are sufficient solids with both negative and positive Hall coefficients. But Kern wants to continue research. The next step will be the production of anisotropic structures with a Hall voltage in the direction of the magnetic field. Normally, Hall voltage is directed vertically to current and magnetic fields. Such unconventional materials might be applied in novel sensors for the direct measurement of magnetic field eddies.

The researchers do not seem to have published a paper about this work.