Tag Archives: Fraunhofer Institute

Identifying minute amounts of nanomaterial in environmental samples

It’s been a while since I’ve had a story from one of Germany’s Franhaufer Institutes. Their stories are usually focused on research that’s about to commercialized but that’s not the case this time according to an April 28, 2016 news item on Nanowerk,

It is still unclear what the impact is on humans, animals and plants of synthetic nanomaterials released into the environment or used in products. It’s very difficult to detect these nanomaterials in the environment since the concentrations are so low and the particles so small. Now the partners in the NanoUmwelt project have developed a method that is capable of identifying even minute amounts of nanomaterials in environmental samples.

An April 28, 2016 Fraunhofer Institute press release, which originated the news item, provides more detail about the technology and about the NanoUmwelt project along with a touch of whimsy,

Tiny dwarves keep our mattresses clean, repair damage to our teeth, stop eggs sticking to our pans, and extend the shelf life of our food. We are talking about nanomaterials – “nano” comes from the Greek word for “dwarf”. These particles are just a few billionths of a meter small, and they are used in a wide range of consumer products. However, up to now the impact of these materials on the environment has been largely unknown, and information is lacking on the concentrations and forms in which they are present there. “It’s true that many laboratory studies have examined the effect of nanomaterials on human and animal cells. To date, though, it hasn’t been possible to detect very small amounts in environmental samples,” says Dr. Yvonne Kohl from the Fraunhofer Institute for Biomedical Engineering IBMT in Sulzbach.

A millionth of a milligram per liter 

That is precisely the objective of the NanoUmwelt project. The interdisciplinary project team is made up of eco- and human toxicologists, physicists, chemists and biologists, and they have just managed to take their first major step forward in achieving their goal: they have developed a method for testing a variety of environmental samples such as river water, animal tissue, or human urine and blood that can detect nanomaterials at a concentration level of nanogram per liter (ppb – parts per billion). That is equivalent to half a sugar cube in the volume of water contained in 1,000 competition swimming pools. Using the new method, it is now possible to detect not just large amounts of nanomaterials in clear fluids, as was previously the case, but also very few particles in complex substance mixtures such as human blood or soil samples. The approach is based on field-flow fractionation (FFF), which can be used to separate complex heterogeneous mixtures of fluids and particles into their component parts – while simultaneously sorting the key components by size. This is achieved by the combination of a controlled flow of fluid and a physical separation field, which acts perpendicularly on the flowing suspension.

For the detection process to work, environmental samples have to be appropriately processed. The team from Fraunhofer IBMT’s Bioprocessing & Bioanalytics Department prepared river water, human urine, and fish tissue to be fit for the FFF device. “We prepare the samples with special enzymes. In this process, we have to make sure that the nanomaterials are not destroyed or changed. This allows us to detect the real amounts and forms of the nanomaterials in the environment,” explains Kohl. The scientists have special expertise when it comes to providing, processing and storing human tissue samples. Fraunhofer IBMT has been running the “German Environmental Specimen Bank (ESB) – Human Samples”since January 2012 on behalf of Germany’s Environment Agency (UBA). Each year the research institute collects blood and urine samples from 120 volunteers in four cities in Germany. Individual samples are a valuable tool for mapping the trends over time of human exposure to pollutants. ”In addition, blood and urine samples have been donated for the NanoUmwelt project and put into cryostorage at Fraunhofer IBMT. We used these samples to develop our new detection method,” says Dr. Dominik Lermen, manager of the working group on Biomonitoring & Cryobanks at Fraunhofer IBMT. After approval by the UBA, some of the human samples in the ESB archive may also be examined using the new method.

Developing new cell culture models

Nanomaterials end up in the environment via different pathways, inter alia the sewage system. Human beings and animals presumably absorb them through biological barriers such as the lung or intestine. The project team is simulating these processes in petri dishes in order to understand how nanomaterials are transported across these barriers. “It’s a very complex process involving an extremely wide range of cells and layers of tissue,” explains Kohl. The researchers replicate the processes in a way as realistic as possible. They do this by, for instance, measuring the electrical flows within the barriers to determine the functionality of these barriers – or by simulating lung-air interaction using clouds of artificial fog. In the first phase of the NanoUmwelt project, the IBMT team succeeded in developing several cell culture models for the transport of nanomaterials across biological barriers. IBMT worked together with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME, which used pluripotent stem cells to develop a model for investigating cardiotoxicity. Empa, the Swiss partner in the project, delivered a placental barrier model for studying the transport of nanomaterials between mother and child.

Next, the partners want to use their method to measure the concentrations of nanoparticles in a wide variety of environmental samples. They will then analyze the results obtained so as to be in a better position to assess the behavior of nanomaterials in the environment and their potential danger for humans, animals, and the environment. “Our next goal is to detect particles in even smaller quantities,” says Kohl. To achieve this, the scientists are planning to use special filters to remove distracting elements from the environmental samples, and they are looking forward to develop new processing techniques.
NanoUmwelt – the objective

The NanoUmwelt research project was launched in October 2014 and will last for 36 months. Its objective is to develop methods for detecting minute amounts of nanomaterials in environmental samples. Using this information, the project partners will assess the effect of nanomaterials on humans, animals, and the environment. They are focusing on commercially significant, slowly degradable, metallic (silver, titanium dioxide), carbonic (carbon nanotubes) and polymer-based (polystyrene) nanomaterials.

http://www.nanopartikel.info/projekte/laufende-projekte/nanoumwelt

NanoUmwelt – the partners

The German Federal Ministry for Education and Research (BMBF) is providing the NanoUmwelt project with 1.8 million euros of funding as part of its NanoCare program. Led by Postnova Analytics GmbH, ten further partners are collaborating together on the project. Besides the Fraunhofer Institutes for Biomedical Engineering IBMT and for Molecular Biology and Applied Ecology IME, these partners include Germany’s Environment Agency, Empa (the Swiss Federal Laboratories for Materials Science and Technology), PlasmaChem GmbH, Senova GmbH (biological sciences and engineering), fzmb GmbH (Research Centre of Medical Technology and Biotechnology), the universities of Trier and Frankfurt, and the Rhine Water Control Station in Worms.

http://www.nanopartikel.info/projekte/laufende-projekte/nanoumwelt

How small is nano?

A nanometer (nm) is a billionth of a meter. To put this into context: the size of a single nanoparticle relative to a football is the same as that of a football relative to the earth. In the main, nanoscopic particles are not new materials. It’s simply that the increased overall surface area of these tiny particles gives them new functionalities as against larger particles of the same material.


The German Environmental Specimen Bank  

The German Environmental Specimen Bank (ESB) provides the country’s Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB) with a scientific basis both for adopting appropriate measures concerning environment and nature conservation and for monitoring the success of those measures. The human samples collected by the Fraunhofer Institute for Biomedical Engineering IBMT on behalf of Germany’s Environment Agency (UBA) give an overview of human exposure to environmental pollutants.

https://www.umweltprobenbank.de/de

Assuming I’ve understood this correctly, the NanoUmwelt project will be ending in 2017 (36 months in total) and the researchers have expended 1/2 of the time (18 months) allotted to developing a technique for measuring nanomaterials of heretofore unheard of quantities in environmental samples. With that done, researchers are now going to use the technique with human samples over the next 18 months.

A step toward commercializing smart windows with electrochromic film

A Dec. 4, 2015 news item on phys.org has reawakened my dream of electrochromic (smart) windows,

EC [electrochromic] film devices have been hampered in making the move from research to innovation by a number of technical and economic obstacles. EELICON [Enhanced Energy Efficiency and Comfort by Smart Light Transmittance Control] aims to overcome these obstacles by removing equipment limitations, automating processes, and validating a possible high-throughput prototype production process for a cost-effective, high-performance EC film technology.

Retrofitting windows with an electrically dimmable plastic film is a dream that is finally coming close to fruition. According to life cycle assessment studies, considerable energy savings may result when such films are included in architectural glazing, appliance doors, aircraft cabin windows, and vehicle sunroofs; and user comfort is enhanced as well.

The EU [European Union]-funded EELICON (Enhanced Energy Efficiency and Comfort by Smart Light Transmittance Control) project is focusing on an innovative switchable light transmittance technology that was developed in a project previously co-funded by the EU Framework Programmes. The project developed mechanically flexible and light-weight electrochromic (EC) film devices based on a conductive polymer nanocomposite technology with a property profile far beyond the current state-of-the art.

A Dec. 3, 2015 CORDIS (EU Community Research and Development Service) press release, which originated the news item, features an interview with the project coordinator and manager,

Dr. Uwe Posset, project coordinator and Expert Group Manager at ZfAE – Center for Applied Electrochemistry, Fraunhofer ISC, discusses the project’s achievements so far.

Do you have any results to show regarding the objectives that you have defined?

We are indeed working on a demonstration line to roll out a possible production process for electrochromic (EC) films, i.e. plastic films that can change colour upon application of a small voltage. Such films can be used to create smart windows for the control of sunlight and glare in buildings and vehicles. This technology is known to have the potential to save substantial amounts of energy for air conditioning. Darkening the film will decrease heat gain in the interior while maintaining the view through the window. The film provides possibilities to retrofit existing windows.

Do you have results from a life cycle assessment (LCA)?

Yes. The results essentially show that the targeted film technology can be produced with less primary energy than a standard EC window. We are currently working on extending the LCA to demonstrate the energy saving potential of the EC film during the use phase.

How much do you expect the technology to cost? How competitive will it be with existing technologies (e.g. price/performance)?

We target a price level of 200 €/m2, which is about a factor of 4 less than standard EC windows based on glass. To be really competitive, an even lower price may be required, but 200 €/m2 is usually discussed in the community as a threshold price for competitiveness. A full performance evaluation is currently in progress. According to discussions with potential end-users, producers and customers, price is the major driver, while some performance aspects may be negotiable, depending on the application.

How easy or difficult will the technology be to commercialise?

It is a complex process presumably requiring an industrial development phase of 2-3 years after the end of the project and substantial investment (currently estimated: €10 million).

Which are the most promising application areas?

Smart windows for energy-efficient buildings, vehicle sunroofs, smart aircraft cabin windows, switchable appliance doors, smart eyewear and visors.

What are the main benefits provided by the technology (any quantitative data would be welcome in addition to a qualitative description)?

There are many benefits. What we are developing is a film-based technology suitable for window integration and retrofitting. It will have short switching times (<1 min as compared to 10-15 min for state-of-the-art EC windows), and most importantly cost-effective, high-throughput production will be possible (roll-to-roll manufacturing).

Our technology will also have a higher bleached state visual light transmittance as compared to state-of-the-art EC windows (60-65 % vs. 50-55 %); a lower darkened state visual light transmittance as compared to state-of-the-art EC windows (5-10 % vs. 10-15 %); it will be fully colourless (“neutral tint”) bleached state with no residual colour or hue.; it will have an appreciable g-value modulation as opposed to liquid crystal-based smart window film technologies; it is mechanically rugged; and it has a large thermal operation range (-25 to +60 °C).

Once the project is completed, what will be the next steps? How do you see the technology evolving in the future?

We will then have to focus on industrial development – scaling from pilot to production scale. Huge markets will become accessible in the future if the price target can be met and minimum performance requirements are fulfilled.

You can find out more about EELICON here.

I’m glad to see they’re finding a way to make the technology affordable and that they’ve tackled the ‘ruggedness’ issue; see my Oct. 9, 2015 posting about smart windows and their need for anti-aging treatment (apparently the windows are prone to mechanical failures over time).

Germany’s nano-supercapacitors for electric cars

Kudos to the writer for giving a dull topic, supercapacitors and electric cars, a jolt of life. From a July 24, 2014 news item on ScienceDaily,

Innovative nano-material based supercapacitors are set to bring mass market appeal a good step closer to the lukewarm public interest in Germany. [emphasis mine] This movement is currently being motivated by the advancements in the state-of-the-art of this device.

A July 1, 2014 Fraunhofer-Gesellschaft press release (also on EurekAlert), which originated the news item and, sadly, did not reveal the writer’s name, goes on in this refreshing fashion,

Electric cars are very much welcomed in Norway and they are a common sight on the roads of the Scandinavian country – so much so that electric cars topped the list of new vehicle registrations for the second time. This poses a stark contrast to the situation in Germany, where electric vehicles claim only a small portion of the market. Of the 43 million cars on the roads in Germany, only a mere 8000 are electric powered. The main factors discouraging motorists in Germany from switching to electric vehicles are the high investments cost, their short driving ranges and the lack of charging stations. Another major obstacle en route to the mass acceptance of electric cars is the charging time involved. The minutes involved in refueling conventional cars are so many folds shorter that it makes the situation almost incomparable. However, the charging durations could be dramatically shortened with the inclusion of supercapacitors. These alternative energy storage devices are fast charging and can therefore better support the use of economical energy in electric cars. Taking traditional gasoline-powered vehicles for instance, the action of braking converts the kinetic energy into heat which is dissipated and unused. Per contra, generators on electric vehicles are able to tap into the kinetic energy by converting it into electricity for further usage. This electricity often comes in jolts and requires storage devices that can withstand high amount of energy input within a short period of time. In this example, supercapacitors with their capability in capturing and storing this converted energy in an instant fits in the picture wholly. Unlike batteries that offer limited charging/discharging rates, supercapacitors require only seconds to charge and can feed the electric power back into the air-conditioning systems, defogger, radio, etc. as required.

So, the Norwegians have embraced electric cars while the Germans have remained reluctant. The writer offers a clear explanation of supercapacitors and mentions a solution for improving the electric vehicle acceptance rate in Germany (from the press release)

Rapid energy storage devices are distinguished by their energy and power density characteristics – in other words, the amount of electrical energy the device can deliver with respect to its mass and within a given period of time. Supercapacitors are known to possess high power density, whereby large amounts of electrical energy can be provided or captured within short durations, albeit at a short-coming of low energy density. The amount of energy in which supercapacitors are able to store is generally about 10% that of electrochemical batteries (when the two devices of same weight are being compared). This is precisely where the challenge lies and what the “ElectroGraph” project is attempting to address.

ElectroGraph is a project supported by the EU and its consortium consists of ten partners from both research institutes and industries. One of the main tasks of this project is to develop new types of supercapacitors with significantly improved energy storage capacities. As the project is approaches its closing phase in June, the project coordinator at Fraunhofer Institute for Manufacturing Engineering and Automation IPA in Stuttgart, Carsten Glanz explained the concept and approach taken en route to its successful conclusion: “during the storage process, the electrical energy is stored as charged particles attached on the electrode material.” “So to store more energy efficiently, we designed light weight electrodes with larger, usable surfaces.”

Next, the ‘nano’ aspect (graphene) of this particular project is explained,

In numerous tests, the researcher and his team investigated the nano-material graphene, whose extremely high specific surface area of up to 2,600 m2/g and high electrical conductivity practically cries out for use as an electrode material. It consists of an ultrathin monolayer lattice made of carbon atoms. When used as an electrode material, it greatly increases the surface area with the same amount of material. From this aspect, graphene is showing its potential in replacing activated carbon – the material that has been used in commercial supercapacitors to date – which has a specific surface area between 1000 and 1800 m2/g.

“The space between the electrodes is filled with a liquid electrolyte,” revealed Glanz. “We use ionic liquids for this purpose. Graphene-based electrodes together with ionic liquid electrolytes present an ideal material combination where we can operate at higher voltages.” “By arranging the graphene layers in a manner that there is a gap between the individual layers, the researchers were able to establish a manufacturing method that efficiently uses the intrinsic surface area available of this nano-material. This prevents the individual graphene layers from restacking into graphite, which would reduce the storage surface and consequently the amount of energy storage capacity. “Our electrodes have already surpassed commercially available one by 75 percent in terms of storage capacity,” emphasizes the engineer. “I imagine that the cars of the future will have a battery connected to many capacitors spread throughout the vehicle, which will take over energy supply during high-power demand phases during acceleration for example and ramming up of the air-conditioning system. These capacitors will ease the burden on the battery and cover voltage peaks when starting the car. As a result, the size of massive batteries can be reduced.”

Whether this effort has already been or, at some time in the future, will be demonstrated is not entirely clear to me,

In order to present the new technology, the ElectroGraph consortium developed a demonstrator consisting of supercapacitors installed in an automobile side-view mirror and charged by a solar cell in an energetically self-sufficient system. The demonstrator will be unveiled at the end of May [2015?] during the dissemination workshop at Fraunhofer IPA.

I imagine improved supercapacitors will be prove to be an enticement for more than one reluctant electric car purchaser no matter where they reside.

Brains, prostheses, nanotechnology, and human enhancement: summary (part five of five)

The Brain research, ethics, and nanotechnology (part one of five) May 19, 2014 post kicked off a series titled ‘Brains, prostheses, nanotechnology, and human enhancement’ which brings together a number of developments in the worlds of neuroscience, prosthetics, and, incidentally, nanotechnology in the field of interest called human enhancement. Parts one through four are an attempt to draw together a number of new developments, mostly in the US and in Europe. Due to my language skills which extend to English and, more tenuously, French, I can’t provide a more ‘global perspective’.

Now for the summary. Ranging from research meant to divulge more about how the brain operates in hopes of healing conditions such as Parkinson’s and Alzeheimer’s diseases to utilizing public engagement exercises (first developed for nanotechnology) for public education and acceptance of brain research to the development of prostheses for the nervous system such as the Walk Again robotic suit for individuals with paraplegia (and, I expect quadriplegia [aka tetraplegia] in the future), brain research is huge in terms of its impact socially and economically across the globe.

Until now, I have not included information about neuromorphic engineering (creating computers with the processing capabilities of human brains). My May 16, 2014 posting (Wacky oxide. biological synchronicity, and human brainlike computing) features one of the latest developments along with this paragraph providing links to overview materials of the field,

As noted earlier, there are other approaches to creating an artificial brain, i.e., neuromorphic engineering. My April 7, 2014 posting is the most recent synopsis posted here; it includes excerpts from a Nanowerk Spotlight article overview along with a mention of the ‘brain jelly’ approach and a discussion of my somewhat extensive coverage of memristors and a mention of work on nanoionic devices. There is also a published roadmap to neuromorphic engineering featuring both analog and digital devices, mentioned in my April 18, 2014 posting.

There is an international brain (artificial and organic) enterprise underway. Meanwhile, work understanding the brain will lead to new therapies and, inevitably, attempts to enhance intelligence. There are already drugs and magic potions (e.g. oxygenated water in Mental clarity, stamina, endurance — is it in the bottle? Celebrity athletes tout the benefits of oxygenated water, but scientists have their doubts, a May 16,2014 article by Pamela Fayerman for the Vancouver Sun). In a June 19, 2009 posting featured Jamais Cascio’s  speculations about augmenting intelligence in an Atlantic magazine article.

While researchers such Miguel Nicolelis work on exoskeletons (externally worn robotic suits) controlled by the wearer’s thoughts and giving individuals with paraplegia the ability to walk, researchers from one of Germany’s Fraunhofer Institutes reveal a different technology for achieving the same ends. From a May 16, 2014 news item on Nanowerk,

People with severe injuries to their spinal cord currently have no prospect of recovery and remain confined to their wheelchairs. Now, all that could change with a new treatment that stimulates the spinal cord using electric impulses. The hope is that the technique will help paraplegic patients learn to walk again. From June 3 – 5 [2-14], Fraunhofer researchers will be at the Sensor + Test measurement fair in Nürnberg to showcase the implantable microelectrode sensors they have developed in the course of pre-clinical development work (Hall 12, Booth 12-537).

A May 14, 2014 Fraunhofer Institute news release, which originated the news item, provides more details about this technology along with an image of the implantable microelectrode sensors,

The implantable microelectrode sensors are flexible and wafer-thin. © Fraunhofer IMM

The implantable microelectrode sensors are flexible and wafer-thin.
© Fraunhofer IMM

Now a consortium of European research institutions and companies want to get affected patients quite literally back on their feet. In the EU’s [European Union’s] NEUWalk project, which has been awarded funding of some nine million euros, researchers are working on a new method of treatment designed to restore motor function in patients who have suffered severe injuries to their spinal cord. The technique relies on electrically stimulating the nerve pathways in the spinal cord. “In the injured area, the nerve cells have been damaged to such an extent that they no longer receive usable information from the brain, so the stimulation needs to be delivered beneath that,” explains Dr. Peter Detemple, head of department at the Fraunhofer Institute for Chemical Technology’s Mainz branch (IMM) and NEUWalk project coordinator. To do this, Detemple and his team are developing flexible, wafer-thin microelectrodes that are implanted within the spinal canal on the spinal cord. These multichannel electrode arrays stimulate the nerve pathways with electric impulses that are generated by the accompanying by microprocessor-controlled neurostimulator. “The various electrodes of the array are located around the nerve roots responsible for locomotion. By delivering a series of pulses, we can trigger those nerve roots in the correct order to provoke motion sequences of movements and support the motor function,” says Detemple.

Researchers from the consortium have already successfully conducted tests on rats in which the spinal cord had not been completely severed. As well as stimulating the spinal cord, the rats were given a combination of medicine and rehabilitation training. Afterwards the animals were able not only to walk but also to run, climb stairs and surmount obstacles. “We were able to trigger specific movements by delivering certain sequences of pulses to the various electrodes implanted on the spinal cord,” says Detemple. The research scientist and his team believe that the same approach could help people to walk again, too. “We hope that we will be able to transfer the results of our animal testing to people. Of course, people who have suffered injuries to their spinal cord will still be limited when it comes to sport or walking long distances. The first priority is to give them a certain level of independence so that they can move around their apartment and look after themselves, for instance, or walk for short distances without requiring assistance,” says Detemple.

Researchers from the NEUWalk project intend to try out their system on two patients this summer. In this case, the patients are not completely paraplegic, which means there is still some limited communication between the brain and the legs. The scientists are currently working on tailored implants for the intervention. “However, even if both trials are a success, it will still be a few years before the system is ready for the general market. First, the method has to undergo clinical studies and demonstrate its effectiveness among a wider group of patients,” says Detemple.

Patients with Parkinson’s disease could also benefit from the neural prostheses. The most well-known symptoms of the disease are trembling, extreme muscle tremors and a short, [emphasis mine] stooped gait that has a profound effect on patients’ mobility. Until now this neurodegenerative disorder has mostly been treated with dopamine agonists – drugs that chemically imitate the effects of dopamine but that often lead to severe side effects when taken over a longer period of time. Once the disease has reached an advanced stage, doctors often turn to deep brain stimulation. This involves a complex operation to implant electrodes in specific parts of the brain so that the nerve cells in the region can be stimulated or suppressed as required. In the NEUWalk project, researchers are working on electric spinal cord simulation – an altogether less dangerous intervention that should however ease the symptoms of Parkinson’s disease just as effectively. “Initial animal testing has yielded some very promising results,” says Detemple.

(For anyone interested in the NEUWalk project, you can find more here,) Note the reference to Parkinson’s in the context of work designed for people with paraplegia. Brain research and prosthetics (specifically neuroprosthetics or neural prosthetics), are interconnected. As for the nanotechnology connection, in its role as an enabling technology it has provided some of the tools that make these efforts possible. It has also made some of the work in neuromorphic engineering (attempts to create an artificial brain that mimics the human brain) possible. It is a given that research on the human brain will inform efforts in neuromorphic engineering and that attempts will be made to create prostheses for the brain (cyborg brain) and other enhancements.

One final comment, I’m not so sure that transferring approaches and techniques developed to gain public acceptance of nanotechnology are necessarily going to be effective. (Harthorn seemed to be suggesting in her presentation to the Presidential Presidential Commission for the Study of Bioethical Issues that these ‘nano’ approaches could be adopted. Other researchers [Caulfield with the genome and Racine with previous neuroscience efforts] also suggested their experience could be transferred. While some of that is likely true,, it should be noted that some self-interest may be involved as brain research is likely to be a fresh source of funding for social science researchers with experience in nanotechnology and genomics who may be finding their usual funding sources less generous than previously.)

The likelihood there will be a substantive public panic over brain research is higher than it ever was for a nanotechnology panic (I am speaking with the benefit of hindsight re: nano panics). Everyone understands the word, ‘brain’, far fewer understand the word ‘nanotechnology’ which means that the level of interest is lower and people are less likely to get disturbed by an obscure technology. (The GMO panic gained serious traction with the ‘Frankenfood’ branding and when it fused rather unexpectedly with another research story,  stem cell research. In the UK, one can also add the panic over ‘mad cow’ disease or Creutzfeldt-Jakob disease (CJD), as it’s also known, to the mix. It was the GMO and other assorted panics which provided the impetus for much of the public engagement funding for nanotechnology.)

All one has to do in this instance is start discussions about changing someone’s brain and cyborgs and these researchers may find they have a much more volatile situation on their hands. As well, everyone (the general public and civil society groups/activists, not just the social science and science researchers) involved in the nanotechnology public engagement exercises has learned from the experience. In the meantime, pop culture concerns itself with zombies and we all know what they like to eat.

Links to other posts in the Brains, prostheses, nanotechnology, and human enhancement five-part series

Part one: Brain research, ethics, and nanotechnology (May 19, 2014 post)

Part two: BRAIN and ethics in the US with some Canucks (not the hockey team) participating (May 19, 2014)

Part three: Gray Matters: Integrative Approaches for Neuroscience, Ethics, and Society issued May 2014 by US Presidential Bioethics Commission (May 20, 2014)

Part four: Brazil, the 2014 World Cup kickoff, and a mind-controlled exoskeleton (May 20, 2014)

Making solar panels beautiful

Researchers at Germany’s Fraunhofer Institute for Applied Optics and Precision Engineering IOF in Jena are working on ways to make solar panels more aesthetically pleasing according to a July 1, 2013 news item on Azonano,

Until now, designers of buildings have no choice but to use black or bluish-gray colored solar panels. With the help of thin-film technologies, researchers have now been able to turn solar cells into colorful creations.

Covering a roof or a façade with standard solar cells to generate electricity will change a building’s original appearance – and not always for the better. At present only dark solar panels are widely available on the market. “Not enough work has been done so far on combining photovoltaics and design elements to really do the term ‘customized photovoltaics’ justice,” says Kevin Füchsel, project manager at the Fraunhofer Institute for Applied Optics and Precision Engineering IOF in Jena.

But things are changing. The IOF physicist has been focusing for the last four years on nanostructured solar cells suitable for mass production as part of a junior research group funded by Germany’s Federal Ministry for Education and Research (BMBF). Together with a Fraunhofer team and scientists from the Friedrich-Schiller University in Jena, the group of optics specialists is looking for cost-effective techniques and manufacturing processes to increase both the efficiency of solar panels and the design flexibility they give architects and designers.

Here’s photomontage illustrating Füchsel’s ideas,

The photomontage shows how the Fraunhofer IAO building in Stuttgart could be fitted with an “efficient design” solar façade. © Fraunhofer IOF

The photomontage shows how the Fraunhofer IAO building in Stuttgart could be fitted with an “efficient design” solar façade.
© Fraunhofer IOF

The July 1, 2013 Fraunhofer Institute news release, which originated the news item, describes Füchsel’s work in more detail,

Füchsel is currently working with his “efficient design” team on the fundamentals of how to make colored solar cells from paper-thin silicon wafers. These will be particularly suited to designs for decorative façades and domestic roofs. The silicon semiconductor material, just a few micrometers thick, absorbs light and turns it into electricity. To enable lots of light to reach the silicon substrate, the semiconductor layer is given an optically neutral protective barrier (insulator), onto which a hundred-nanometer-thick oxide layer is applied. This transparent conductive oxide (TCO) conducts electricity, and is there primarily to guide as many light particles as possible to the semiconductor layer below. “TCO has a lower refractive index than silicon, so it works as an anti-reflective coating,” Füchsel says.

The simple construction of this SIS (semiconductor-insulator-semiconductor) solar cell, with its transparent outer layer, has a further advantage: Not only does it capture more light, it means solar panels can be made in different colors and shapes. “The color comes from changing the physical thickness of the transparent conductive oxide layer, or modifying its refractive index,” Füchsel says. The Jena-based researchers have thus managed to combine wafer-based silicon with processes borrowed from thin-film photovoltaics. They are also pioneering the use of innovative coating materials. Indium tin oxide is the most common material used today, but it is expensive.  The IOF laboratory is working on how to use cheaper zinc oxide with added aluminum. New opportunities in façade design are being opened up not just by SIS solar cells, however, but also by dye solar modules and flexible organic solar cells.

But how does color affect the efficiency of these new SIS modules? “Giving solar cells color doesn’t really affect their efficiency. The additional transparent TCO layer has barely any impact on the current yield,” Füchsel says. Simulations showed that SIS cells could be up to 20 percent efficient. In practice, the efficiency depends on the design of the solar panels and the direction the building faces. But not every color allows you to generate the same amount of electricity. There are restrictions for example with certain blends of red, blue and green.

To connect several solar cells to create a single module the IOF scientist will use laser-based optical welding processes. They enable accurate work at a micrometer scale and do not damage the surrounding material. Researchers are also developing an inkjet printing process to contact the conductive TCO later on the silicon wafer. This will make manufacturing faster and allow additional degrees of flexibility in design. SIS solar cells could even be used to make large billboards that produce their own electricity. Patents already cover the production of colored cells, as well as the ability to integrate design elements into solar panels and whole modules. “This opens up numerous possibilities to use a building to communicate information, displaying the name of a company or even artistic pictures,” Füchsel says.

I look forward to a more beautiful future.

Glove sensors and toxic substances

Gloves that change colour as a signal you’re handling toxic substances have been developed by a research team at  the Fraunhofer Institute according to a May 2, 2013 Fraunhofer Research Institution for Modular Solid State Technologies EMFT news release (also on EurekAlert as a re-issued June 7, 2013 news release),

Employees in chemical production, the semiconductor industry or in laboratories are frequently exposed to harmful substances. The problem: Many of these aggressive substances are imperceptible to human senses, which makes handling them so risky. That’s why there is a broad range of solutions that employers can use to protect their staff from hazardous substances – from highly sensitive measuring equipment to heat imaging cameras. Soon, this spectrum will be enhanced by one more clever solution that is easy to handle, and that dispenses with a power supply. Researchers at the Fraunhofer Research Institution for Modular Solid State Technologies EMFT in Regensburg have engineered a glove that recognizes if toxic substances are present in the surrounding air.

Here’s an image of the glove,

The sensor glove turns blue in the presence of hazardous substances. (© Fraunhofer EMFT)

The sensor glove turns blue in the presence of hazardous substances. (© Fraunhofer EMFT)

The news release provides more details,

The protective glove is equipped with custom-made sensor materials and indicates the presence of toxic substances by changing colors. In this regard, the scientists adapted the materials to the corresponding analytes, and thus, the application. The color change – from colorless (no toxic substance) to blue (toxic substance detected), for example – warns the employee immediately. …

….

The warning signal is triggered by an indicator dye integrated into the glove that reacts to the presence of analytes, in this case, the toxic substances. The experts at EMFT used a variety of techniques in order to furnish textiles with sensor-activated dyes. The sensor-activated dyes are applied to the clothing with the customary dye and print process, for example, by affixing them in an immersion bath. Previously, the researchers used targeted chemical modification to adapt the color molecules to the fiber properties of the respective textile. Alternatively, the textiles can also be coated with sensor particles that are furnished with sensor dyes. For this purpose, the scientists integrated the dye molecules either into commercial pigments or they built them up on an entirely synthetic basis. The pigments are then manufactured according to the customary textile finishing process, for instance, the sensor particles are also suitable for silkscreening. “Which version we opt for depends on the requirements of the planned application,” says Trupp [Dr. Sabine Trupp, head of the Fraunhofer EMFT Sensor Materials group].

The challenge lies foremost in the tailored development of sensor dyes. “The dye molecule must detect a specific analyte in a targeted manner – only then will a chemical reaction occur. Moreover, the dye must adhere securely; it cannot disappear due to washing. We aim for the customer’s preferences in the color selection as well. All of these aspects must be kept in mind when developing the molecule and pigment properties,” explains Trupp.

The technology could be extended to do more and could be adapted for other applications (from the news release),

The expert already has new ideas about how the solution could be developed further. For example, a miniaturized sensor module, integrated into textiles, could record toxic substances, store the measurement data and even transmit them to a main unit. This way, you could document how frequently an individual within a hazardous environment was exposed to poisonous concentrations over a longer period of time.

The researchers also envision other potential applications in the foodstuffs industry: In the future, color indicator systems integrated into foils or bottle closures are intended to make the quality status of the packaged foods visible. Because the sell-by date does not represent a guarantee of any kind. Foodstuffs may often spoil prematurely – unnoticed by the consumer – due to a packaging error, or in the warehousing, or due to disruptions in the refrigeration chain. Oil-based and fat-containing products are specifically prone to this, as are meats, fish and ready meals.

The notion that food packaging could be designed to include sensors that alert consumers and retailers about product spoilage is not new and was mentioned recently and briefly in my Mar. 25, 2013 posting which featured excerpts from an interview with biotechnologist Christoph Meili about nanotechnology-enabled food packaging.

Car engines, tribological (friction-oriented) performance, and the Fraunhofer Institutes

A June 3, 2013 news item on Nanowerk about the TRIBOMAN project at the Fraunhofer Institute focuses on friction and combustion engines,

Within the scope of the “TRIBOMAN“ project, researchers at five Fraunhofer Institutes are working to develop production methods and processes to improve combustion engines‘ tribological (meaning friction-related) performance. The focus is on components exposed to particularly high levels of friction, such as the running surfaces of engine cylinders. „Our common approach is to move the process of forming marginalized layers to an earlier stage in production,“ explains Torsten Schmidt from the Fraunhofer Institute for Machine Tools and Forming Technology IWU in Chemnitz.

Schmidt and his team have developed optimized production technologies for precision finishing in this connection. “For precision drilling of running surfaces on cylinders, we use defined cutting edges with a specific design. This results in very high surface quality,“ Schmidt adds. “We also systematically use the force of the machining process to promote ‚grain refinement‘ – meaning the hardening of the materials – even during production.“

The June 3, 2013 Fraunhofer Institute news release, which originated the news item, provides some context for the TRIBOMAN project,

If a new car engine is to run, smoothly,“first it has to be properly run in: drivers should avoid quick acceleration and permanent short trips during the first 1000 kilometers, for instance. Why is this “grace period“ necessary at all? When an engine is being run in, the peripheral zone on the articulations – the components in mechanical contact with one another – changes as a result of friction: the surface itself becomes “smoother“, and the granularity of the microstructure becomes finer at a material depth of roughly 500 to 1000 nanometers (nm), creating a nanocrystalline layer.

Quite a bit of friction has taken place, though, by the time this nano scale layer has formed. That is why, even now, a large share of the energy is lost to friction during the phase in which an engine is run in. Surface running properties are also a function of the customer‘s behavior during the running-in phase. A critical topic for the automotive industry: against the backdrop of increasingly scarce resources and the need to reduce CO2 emissions, reductions of friction loss has top priority on the development agenda.

The results, according to the Fraunhofer news release,

Using a single cylinder test engine with cylinder running surfaces of aluminum, researchers at the Fraunhofer Institute for Mechanics of Materials IWM in Freiburg have already documented the first positive results of this kind of modified finishing: analyses of the processed cylinder surfaces showed a significantly lower grain size compared to conventional methods. The surface microgeometry is comparable to the cylinder running surfaces of well-run-in cylinders. Researchers are currently working to adapt their method to new development trends in automobile manufacturing such as the introduction of biofuels: since the ethanol content of biofuels is higher, aluminum components are now usually fitted with a coating layer to protect them from corrosion more effectively.

For those who would like to learn more about the TRIBOMAN project and have the German language skills, go here.

Cambridge University wants to take its flexible opals to market

Structural colour due to nanoscale structures such as those found on Morpho butterfly wings, jewel beetles, opals, and elsewhere is fascinating to me (Feb. 7, 2013 posting). It would seem many scientists share my fascination  including these groups at the UK’s University of Cambridge and Germany’s Fraunhofer Institute, from the May 30, 2013 University of Cambridge news release (also on EurekAlert),

Instead of through pigments, these ‘polymer opals’ get their colour from their internal structure alone, resulting in pure colour which does not run or fade. The materials could be used to replace the toxic dyes used in the textile industry, or as a security application, making banknotes harder to forge. Additionally, the thin, flexible material changes colour when force is exerted on it, which could have potential use in sensing applications by indicating the amount of strain placed on the material.

The most intense colours in nature – such as those in butterfly wings, peacock feathers and opals – result from structural colour. While most of nature gets its colour through pigments, items displaying structural colour reflect light very strongly at certain wavelengths, resulting in colours which do not fade over time.

In collaboration with the DKI (now Fraunhofer Institute for Structural Durability and System Reliability) in Germany, researchers from the University of Cambridge have developed a synthetic material which has the same intensity of colour as a hard opal, but in a thin, flexible film.

Here’s what the researchers’ synthetic opal looks like,

Polymer Opals Credit: Nick Saffel [downloaded from http://www.cam.ac.uk/research/news/flexible-opals]

Polymer Opals Credit: Nick Saffel [downloaded from http://www.cam.ac.uk/research/news/flexible-opals]

The news release provides a brief description of naturally occurring opals and contrasts them with the researchers’ polymer opals,

Naturally-occurring opals are formed of silica spheres suspended in water. As the water evaporates, the spheres settle into layers, resulting in a hard, shiny stone. The polymer opals are formed using a similar principle, but instead of silica, they are constructed of spherical nanoparticles bonded to a rubber-like outer shell. When the nanoparticles are bent around a curve, they are pushed into the correct position to make structural colour possible. The shell material forms an elastic matrix and the hard spheres become ordered into a durable, impact-resistant photonic crystal.

“Unlike natural opals, which appear multi-coloured as a result of silica spheres not settling in identical layers, the polymer opals consist of one preferred layer structure and so have a uniform colour,” said Professor Jeremy Baumberg of the Nanophotonics Group at the University’s Cavendish Laboratory, who is leading the development of the material.

Like natural opals, the internal structure of polymer opals causes diffraction of light, resulting in strong structural colour. The exact colour of the material is determined by the size of the spheres. And since the material has a rubbery consistency, when it is twisted and stretched, the spacing between spheres changes, changing the colour of the material. When stretched, the material shifts into the blue range of the spectrum, and when compressed, the colour shifts towards red. When released, the material will return to its original colour.

I find the potential for use in the textile industry a little more interesting than the anti-counterfeiting application. (There’s a Canadian company, Nanotech Security Corp., a spinoff from Simon Fraser University, which capitalizes on the Blue Morpho butterfly wing’s nanoscale structures for an anti-counterfeiting application as per my first posting about the company on Jan. 17, 2011.) There has been at least one other attempt to create a textile that exploits structural colour. Unfortunately Teijin Fibres has stopped production of its morphotex, as per my April 12, 2012 posting.

Here’s what the news release has to say about textiles and the potential importance of structural colour,

The technology could also have important uses in the textile industry. “The World Bank estimates that between 17 and 20 per cent of industrial waste water comes from the textile industry, which uses highly toxic chemicals to produce colour,” said Professor Baumberg. “So other avenues to make colour is something worth exploring.” The polymer opals can be bonded to a polyurethane layer and then onto any fabric. The material can be cut, laminated, welded, stitched, etched, embossed and perforated.

The researchers have recently developed a new method of constructing the material, which offers localised control and potentially different colours in the same material by creating the structure only over defined areas. In the new work, electric fields in a print head are used to line the nanoparticles up forming the opal, and are fixed in position with UV light. The researchers have shown that different colours can be printed from a single ink by changing this electric field strength to change the lattice spacing.

As for wanting to take this research to market, from the news release,

Cambridge Enterprise, the University’s commercialisation arm, is currently looking for a manufacturing partner to further develop the technology and take polymer opal films to market.

For more information, please contact sarah.collins@admin.cam.ac.uk.

The reference to opals reminded me of yet another Canadian company exploring the uses of structural colour, Opalux, as per my Jan. 31, 2011 posting.

Anti-theft with smart fabrics

When you cut or tear the new smart fabric developed at the Fraunhofer Institute, an alarm is triggered. Here’s a little more about the fabric from the Sept. 6, 2012 news item on physorg.com,

Thieves are unlikely to appreciate this fabric, which looks innocuous but in fact incorporates a fine web of conductive threads connected to a microcontroller that detects warning signals emitted when the fabric is cut and triggers an alarm. This system can be used to protect buildings, bank vaults, and trucks against even the most wily of intruders. Vehicles parked overnight at truck stops are particularly vulnerable to attacks by thieves who slit open the canvas tarp covering the trailer while the driver is asleep and make off with the cargo. If the tarp were made from the smart fabric, the driver in the bunk would be immediately alerted.

The smart fabric was developed by researchers at the Fraunhofer Institute for Reliability and Microintegration IZM in Berlin in collaboration with the Technische Universität Berlin and ETTLIN Spinnerei und Weberei Produktions GmbH. The company in Ettlingen [Germany] manufactures technical textiles, among other things, and has filed a patent for the innovative fabric.

The Sept.5, 2012 Fraunhofer Institute press release (which originated the news item) provides detail about the technology and its advantages,

What makes this solution unique is the fact that it not only signals the presence of intruders but also indicates the precise point of forced entry. The fine lattice of conductive threads woven into the fabric enables the place where it was cut to be identified to the nearest centimeter. Other solutions currently on the market require a complex system of optical fibers, which naturally makes them more expensive.

There are also other reasons why this fabric is cheap to produce. The process makes exclusive use of standard materials and components such as silver-coated conductive threads and a simple but robust signal evaluation system. A further advantage is that “the conductive thread can be incorporated in the polyester substrate using an industry-standard textile-weaving process,” explains Simon [IZM project manager Erik Simon]. The result is reams of fabric that can be trimmed to any length and customized to provide the desired functionality for surfaces of any size, from one square meter upward.

The conductive lattice and the data-processing module that triggers the alarm in the monitoring center are incorporated in a low-temperature process using joining techniques borrowed from the semiconductor industry such as adhesive pressure bonding and non-destructive welding. “This method has never been used before in this kind of application,” says Simon, who describes the process as “simple and reliable”. And this is precisely the selling point of the solution: the ability to create an entirely new product with immediately appreciable benefits using existing materials and joining techniques.

Part of what makes this an ‘exciting’ development is the fabric’s durability (from the Fraunhofer Institute press release),

The all-important question was to determine the fabric’s reliability and durability, especially with respect to the electrical contacts. To verify this, the textile alarm system was put through a grueling series of tests in the IZM laboratories. It was beaten and tumbled in a washing machine at 40 degrees Celsius, and exposed to the elements for 1,000 hours at a relative humidity of 85 percent and a temperature of 85 degrees Celsius. It was then placed in a furnace in which it was subjected to 1,000 temperature cycles ranging from minus 40 to plus 85 degrees Celsius. The smart textile stood up to this torture without flinching. Simon: “It didn’t fail once.”

Of course, at some point, technically astute and determined thieves will find a way to hack the fabric alarm but in the meantime, some of us can rest more easily.

I’ll cry if I want to—measuring glucose levels in your tears

If you look closely, you’ll see a tiny sensor beneath the eye. Inside there are nano-size biosensors which can detect your glucose levels in your tears (or sweat, if prefer). For a diabetic, checking glucose levels has to be done daily by pricking the skin to draw blood.

With this nano-sized biosensor, diabetes patients can measure their glucose levels with the fluid from the tears of their eyes. (copyright Fraunhofer IMS)

Sept. 4, 2012 news item on Nanowerk provides more details,

Pricking a finger everyday is just part of everyday life for many diabetes patients. A non-invasive measurement approach could release them from the constant pain of pin pricks. The linchpin is a biosensor engineered by Fraunhofer researchers: A tiny chip combines measurement and digital analysis – and can be radioed to a mobile device.

The Sept. 3, 2012 news release from Fraunhofer, an application-oriented research organization, provides more detail about the technology and its advantages,

The principle of measurement involves an electrochemical reaction that is activated with the aid of an enzyme. Glucose oxidase converts glucose into hydrogen peroxide (H2O2) and other chemicals whose concentration can be measured with a potentiostat. This measurement is used for calculating the glucose level. The special feature of this biosensor: the chip, measuring just 0.5 x 2.0 millimeters, can fit more than just the nanopotentiostat itself. Indeed, Fraunhofer researchers have attached the entire diagnostic system to it. “It even has an integrated analog digital converter that converts the electrochemical signals into digital data,” explains Tom Zimmermann, business unit manager at IMS. The biosensor transmits the data via a wireless interface, for example to a mobile receiver. Thus, the patient can keep a steady eye on his or her glucose level. “In the past, you used to need a circuit board the size of a half-sheet of paper,” says Zimmermann. “And you also had to have a driver. But even these things are no longer necessary with our new sensor.”

The minimal size is not the only thing that provides a substantial advantage over previous biosensors of this type. In addition, the sensor consumes substantially less power. Earlier systems required about 500 microamperes at five volts; now, it is less than 100 microamperes. That increases the durability of the system – allowing the patient to wear the sensor for weeks, or even months. The use of a passive system makes this durability possible. The sensor is able to send and receive data packages, but it can also be supplied with power through radio frequency.

The glucose sensor was engineered by the researchers at Noviosens, a Dutch medical technology firm. Since it can be manufactured so cost-effectively, it is best suited for mass production.

This looks pretty exciting. Of course, I’d still like to see find out the level of accuracy for this new way to measure glucose as compared to the current technique (no mention of clinical trials). Also, how do you affix the sensor to your skin? Is there a glue? Can you accidentally wash, wipe,  or knock your sensor off? Or, is it difficult to remove? For people who do choose to wear it beneath an eye, how does makeup affect the sensor?

Assuming that the accuracy is the same or better and that any pitfalls due to wearing a sensor have been addressed, I imagine the next hurdle will be scaling up production.

As for the ‘I’ll cry if I want to’ part of the headline for this piece, I have shamelessly borrowed [corrected 2:27 pm PDT, Sept. 5, 2012] from Lesley Gore’s 1963 hit, ‘I’s my party and I’ll cry if want to’. I’ve never loved the lyrics (for the most part) but the chorus has a haunting quality (as far as I’m concerned). Here is Lesley Gore,