Posts Tagged ‘carbon nanotubes’

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No more carbon nanotubes from Bayer MaterialScience

Thursday, May 9th, 2013

A May 8, 2013 news item on Nanowerk proclaims,

Bayer MaterialScience intends to focus its development activities more intently on topics that are closely linked to its core business. For that reason the company will bring its work on carbon nanotubes (CNTs) to a close. Precisely how the research results and know-how for the production and application CNT will be used further will be determined shortly.

Researchers from Bayer MaterialScience had collaborated with external partners in recent years to resolve complex issues related to the safe production of specific carbon nanotubes. [emphasis mine] Methods for scaling up the production processes were developed, as were new generations of catalysts and new types of products.

The timing for this announcement from Bayer MateriaScience is interesting given that the US National Institute of Occupational Health and Safety (NIOSH) just announced some stringent recommendations (almost zero) for occupational exposure to carbon nanofibers and carbon nanotubes (my Apr. 28, 2013 posting).

The May 8, 2013 Bayer MaterialScience news release, which originated the news item, provides more detail about the business decision,

Much of the knowledge gleaned over recent years was made available to other companies and research institutions within the Innovation Alliance Carbon Nanotubes (Inno.CNT), which counts Bayer MaterialScience among its roughly 90 members.

“We remain convinced that carbon nanotubes have huge potential,” says Patrick Thomas, Chief Executive Officer of Bayer MaterialScience. It has been found, however, that the potential areas of application that once seemed promising from a technical standpoint are currently either very fragmented or have few overlaps with the company’s core products and their application spectrum.

“For Bayer MaterialScience, groundbreaking applications for the mass market relating to our own portfolio and therefore comprehensive commercialization are not likely in the foreseeable future,” says Thomas. Nonetheless, this know-how provides an important basis for a possible later use of CNT, for example in the optimization of lithium ion batteries, Thomas says. “We are currently in contact with potential interested parties regarding the specific application of the know-how generated,” Thomas adds.

The conclusion of the nano projects has no impact on the headcount. All 30 people employed in this sector will be transferred to other suitable positions within the Group.

I”m glad to hear no one will lose their job.

Finally, I recall reading somewhere that there was a glut of carbon nanotube production and taking that with the recent NIOSH recommendation and Bayer’s claim of poor prospects for commercialization, it seems like one of those decisions that made itself.

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“Control my chirality, please,” said the carbon nanotube to the researchers

Tuesday, April 30th, 2013

A combined Finnish, Russian, and Danish team have found a way to control the chirality of single-walled carbon nanotubes according to an Apr. 30, 2013 news item on Azonano,

An ultimate goal in the field of carbon nanotube research is to synthesise single-walled carbon nanotubes (SWNTs) with controlled chiralities. Twenty years after the discovery of SWNTs, scientists from Aalto University in Finland, A.M. Prokhorov General Physics Institute RAS in Russia and the Center for Electron Nanoscopy of Technical University of Denmark (DTU) have managed to control chirality in carbon nanotubes during their chemical vapor deposition synthesis.

The Aalto University Apr. 29, 2013 news release, which originated the news item, goes on to explain,

 Over the years, substantial progress has been made to develop various structure-controlled synthesis methods. However, precise control over the chiral structure of SWNTs has been largely hindered by a lack of practical means to direct the formation of the metal nanoparticle catalysts and their catalytic dynamics during tube growth.

– We achieved an epitaxial formation of Co nanoparticles by reducing a well-developed solid solution in CO, reveals Maoshuai He, a postdoctoral researcher at Aalto University School of Chemical Technology.

– For the first time, the new catalyst was employed for selective growth of SWNTs, adds senior staff scientist Hua Jiang from Aalto University School of Science.

By introducing the new catalysts into a conventional CVD reactor, the research team demonstrated preferential growth of semiconducting SWNTs (～90%) with an exceptionally high population of (6,5) tubes (53%) at 500 °C. Furthermore, they also showed a shift of the chiral preference from (6,5) tubes at 500 °C  to (7, 6) and (9, 4) nanotubes at 400 °C.

– These findings open new perspectives both for structural control of SWNTs and for elucidating their growth mechanisms, thus are important for the fundamental understanding of science behind nanotube growth, comments Professor Juha Lehtonen from Aalto University.

For anyone like me who needs a description of chirality, there’s this from Wikipedia,

Chirality (pron.: /kaɪˈrælɪtiː/) is a property of asymmetry important in several branches of science. The word chirality is derived from the Greek, χειρ (kheir), “hand”, a familiar chiral object.

An object or a system is chiral if it is not identical to its mirror image, that is, it cannot be superposed onto it. A chiral object and its mirror image are called enantiomorphs (Greek opposite forms) or, when referring to molecules, enantiomers. A non-chiral object is called achiral (sometimes also amphichiral) and can be superposed on its mirror image.

…

Human hands are perhaps the most universally recognized example of chirality: The left hand is a non-superimposable mirror image of the right hand; no matter how the two hands are oriented, it is impossible for all the major features of both hands to coincide.[2] This difference in symmetry becomes obvious if someone attempts to shake the right hand of a person using his left hand, or if a left-handed glove is placed on a right hand. In mathematics chirality is the property of a figure that is not identical to its mirror image.

One of the researchers notes why they, or anyone else, would want to control the chirality of carbon nanotubes, from the news release,

– Chirality defines the optical and electronic properties of carbon nanotubes, so controlling it is a key to exploiting their practical applications, says Professor Esko I. Kauppinen, the leader of the Nanomaterials Group in Aalto University School of Science.

ETA Apr. 30, 2013 at 4:20 pm PDT: Here’s a link to and a citation for the team’s published paper,

Chiral-Selective Growth of Single-Walled Carbon Nanotubes on Lattice-Mismatched Epitaxial Cobalt Nanoparticles by Maoshuai He, Hua Jiang, Bilu Liu, Pavel V. Fedotov, Alexander I. Chernov, Elena D. Obraztsova, Filippo Cavalca, Jakob B. Wagner, Thomas W. Hansen, Ilya V. Anoshkin, Ekaterina A. Obraztsova, Alexey V. Belkin, Emma Sairanen, Albert G. Nasibulin,  Juha Lehtonen, & Esko I. Kauppinen. Scientific Reports 3, Article number 1460  doi:10.1038/srep01460 Published15 March 2013

This article is open access.

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US National Institute of Occupational Health and Safety sets recommendations for workplace exposure to carbon nanofibers/nanotubes

Friday, April 26th, 2013

Earlier this week, the US National Institute of Occupational Health and Safety (NIOSH) set recommendations for workplace exposure to carbon nanotubes and carbon nanofibers. According to the Apr. 24, 2013 media advisory from the US Centers for Disease Control and Prevention (NIOSH’s parent agency), the recommendations have been issued in the new Current Intelligence Bulletin (CIB) no. 65. From CIB No. 65,

NIOSH is the leading federal agency conducting research and providing guidance on the occupational safety and health implications and applications of nanotechnology. As nanotechnology continues to expand into every industrial sector, workers will be at an increased risk of exposure to new nanomaterials. Today, nanomaterials are found in hundreds of products, ranging from cosmetics, to clothing, to industrial and biomedical applications. These nanoscale-based products are typically called “first generation” products of nanotechnology. Many of these nanoscale-based products are composed of engineered nanoparticles, such as metal oxides, nanotubes, nanowires, quantum dots, and carbon fullerenes (buckyballs), among others. Early scientific studies have indicated that some of these nanoscale particles may pose a greater health risk than the larger bulk form of these materials.

Results from recent animal studies indicate that carbon nanotubes (CNT) and carbon nanofibers (CNF) may pose a respiratory hazard. CNTs and CNFs are tiny, cylindrical, large aspect ratio, manufactured forms of carbon. There is no single type of carbon nanotube or nanofiber; one type can differ from another in shape, size, chemical composition (from residual metal catalysts or functionalization of the CNT and CNF) and other physical and chemical characteristics. Such variations in composition and size have added to the complexity of understanding their hazard potential. Occupational exposure to CNTs and CNFs can occur not only in the process of manufacturing them, but also at the point of incorporating these materials into other products and applications. A number of research studies with rodents have shown adverse lung effects at relatively low-mass doses of CNT and CNF, including pulmonary inflammation and rapidly developing, persistent fibrosis. Although it is not known whether similar adverse health effects occur in humans after exposure to CNT and CNF, the results from animal research studies indicate the need to minimize worker exposure.

This NIOSH CIB, (1) reviews the animal and other toxicological data relevant to assessing the potential non-malignant adverse respiratory effects of CNT and CNF, (2) provides a quantitative risk assessment based on animal dose-response data, (3) proposes a recommended exposure limit (REL) of 1 μg/m3 elemental carbon as a respirable mass 8-hour time-weighted average (TWA) concentration, [emphasis mine] and (4) describes strategies for controlling workplace exposures and implementing a medical surveillance program. The NIOSH REL is expected to reduce the risk for pulmonary inflammation and fibrosis. However, because of some residual risk at the REL and uncertainty concerning chronic health effects, including whether some types of CNTs may be carcinogenic, continued efforts should be made to reduce exposures as much as possible.

The recommended exposure, for those of us who can’t read the technical notation, translates to one microgram per cubic meter per eight-hour workday.  In other words, almost zero. Note that this is a recommendation and not a regulation. H/T Apr. 26, 2013 article by Elizabeth Wiese for USA Today

My Mar. 12, 2013 posting highlights some of the NIOSH research which preceded this recommendation.

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Beginner’s guide to carbon nanotubes and nanowires

Thursday, April 11th, 2013

There’s a very nice Apr. 11, 2013  introductory article by David L. Chandler for the Massachusetts Institute of Technology (MIT) news office) about carbon and other nanotubes and nanowires,

The initial discovery of carbon nanotubes — tiny tubes of pure carbon, essentially sheets of graphene rolled up unto a cylinder — is generally credited to a paper published in 1991 by the Japanese physicist Sumio Ijima (although some forms of carbon nanotubes had been observed earlier). Almost immediately, there was an explosion of interest in this exotic form of a commonplace material. Nanowires — solid crystalline fibers, rather than hollow tubes — gained similar prominence a few years later.

Due to their extreme slenderness, both nanotubes and nanowires are essentially one-dimensional. “They are quasi-one-dimensional materials,” says MIT associate professor of materials science and engineering Silvija Gradečak: “Two of their dimensions are on the nanometer scale.” This one-dimensionality confers distinctive electrical and optical properties.

For one thing, it means that the electrons and photons within these nanowires experience “quantum confinement effects,” Gradečak says. And yet, unlike other materials that produce such quantum effects, such as quantum dots, nanowires’ length makes it possible for them to connect with other macroscopic devices and the outside world.

The structure of a nanowire is so simple that there’s no room for defects, and electrons pass through unimpeded, Gradečak explains. This sidesteps a major problem with typical crystalline semiconductors, such as those made from a wafer of silicon: There are always defects in those structures, and those defects interfere with the passage of electrons.

H/T Nanowerk Apr. 11, 2013 news item. There’s more to read at the MIT website and I recommend this as a good beginner’s piece since the focus is entirely on what carbon nanotubes and nanowires are , how they are formed, and which distinctive properties are theirs. You can find some of this information in the odd paragraph of a news release touting the latest research but I’m very excited to find this much explanatory material in one place.

Another very good explanatory piece, this one focused on carbon nanotubes and risk, is a video produced by Dr. Andrew Maynard for his Risk Bites series. I featured and embedded it in my Mar. 15, 2013 posting. titled, The long, the short, the straight, and the curved of them: all about carbon nanotubes.  You can also find the video in Andrew’s Mar. 14, 2013 posting on his 2020 Science blog where he also writes about the then recently released information from the US National Institute of Occupational Health and Safety on carbon nanotubes and toxicity.

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Safe Work Australia’s two new reports, Europe’s Nanodevice project, and the UK’s HSE nanomaterials handling

Monday, April 1st, 2013

Over the last few weeks in March (2013), there was a sudden burst of health and safety reports and initiatives released by Safe Work Australia, the European Commission’s Nanodevice project, and the UK’s Health and Safety Executive, respectively.

According to a Mar. 19, 2013 news item on Nanowerk, Safe Work Australia released two reports (Note: Links have been removed),

Safe Work Australia Chair Ann Sherry AO today released two research reports examining nanotechnology work health and safety issues.

The reports: Investigating the emissions of nanomaterials from composites and other solid articles during machining process and Evaluation of potential safety (physicochemical) hazards associated with the use of engineered nanomaterials are part of a comprehensive program of work on nanotechnology safety managed by Safe Work Australia which started in 2007.

The March 18, 2013 Safe Work Australia media release, which originated the news item,  provides some information about the approaches and models being used to analyse and develop policies,

In releasing the reports Ms Sherry noted the perceived safety risks of nanomaterials and that a precautionary approach is being taken by the Commonwealth towards nanomaterials under the National Enabling Technologies Strategy.“

While the risk to human health and safety from a number of these materials and applications is low some nanomaterials are potentially more hazardous, for example carbon nanotubes,” Ms Sherry said.

“The National Industrial Chemicals Notification and Assessment Scheme (NICNAS) has recommended carbon nanotubes be classified as suspected carcinogens unless product-specific evidence suggests otherwise.”

Under the model Work Health and Safety (WHS) laws all duties which apply to the handling of materials and to technologies in general also apply to nanomaterials and nanotechnologies. Minimisation of exposure to nanomaterials at work is essential until there is sufficient data to rule out hazardous properties. Research has shown if conventional engineering controls are designed and maintained effectively, exposure to nanomaterials can be significantly reduced.

As a result of the findings of these reports Safe Work Australia will prepare guidance material on combustible dust hazards including nanomaterials.

Here’s more about the reports (from their respective webpages),

Investigating the emissions of nanomaterials from composites and other solid articles during machining processes

This report by CSIRO considers the potential health risk of emissions from machining processes.

The report finds that significant quantities of material, which can present health risk, are emitted from composites by high energy machining processes like cutting with an electric disc saw or band saw. If the composite contains a hazardous nanomaterial, the health risk from the dust may be higher. Lower energy processes like manual cutting will result in lower exposures and lower potential health risk.

Evaluation of potential safety hazards associated with the use of engineered nanomaterials

This report by Toxikos Pty Ltd examines safety hazards associated with engineered nanomaterials and the implications in regard to workers safety.

The report finds that dust clouds of some engineered nanomaterials could give rise to strong explosions if the dust cloud contains a high enough concentration of nanomaterials and if an ignition source is also present. The report gives examples of these. However in a well-managed workplace, emissions from nanotechnology processes will be very significantly below the minimum dust concentration needed for an explosion.

A Mar. 20, 2013 news item on Nanowerk focused on the European Commission’s Nanodevice project,

European researchers in the Nanodevice project are investigating the safety aspects of nanomaterial production. Their plan laid down in 2009 was to develop new concepts, reliable methods and portable devices for detecting, analysing and monitoring airborne ENMs in the workplace. The latest feedback from the team suggests the project has delivered on its promise.

The project has concluded work on seven new ‘nanodevices’, which have been calibrated and tested for use in work environments exposed to nanoparticles. This work, alongside findings from materials studies and research into the association between ENM properties and their biological impacts, will appear in a new nanosafety handbook, called “Safe handling of manufactured nanomaterials: particle measurement exposure assessment and risk management”.

Complex research like this calls for an integrated, multidisciplinary approach,” confirms Nanodevice’s project leader, Dr Kai Savolainen of the Finnish Institute of Occupational Health.

What makes this particular health and safety project special is the focus on affordable monitoring for small and medium-size companies,

With affordable, portable equipment, even small companies can regularly measure their workers’ exposure to potentially harmful particles. When compared with a growing body of data from other workplaces, a more accurate assessment of risk and occupational health and safety emerges.

Prior to Nanodevice’s portable solutions, regular nanosafety checks could cost up to €200 000. The instrumentation hauled in from outside weighed hundreds of kilos and needed several experts to gather and analyse data from multiple sites. Big companies could afford this, but Europe’s important SME sector struggled with the cost.

“We’ve developed devices like a personal nanoparticle monitor for less than €200 that almost any company can afford and quickly learn to use,” says Dr Savolainen. Worn by a worker, the system collects exposure information, but needs to be plugged into a computer to download the data. This is not ideal, so Nanodevice is keen to develop this into a real-time sensing and monitoring device linked to the internet and databases.

“Today, lack of ‘big’ accurate data makes it hard to know if exposure values are too low,” explains Dr Savolainen, “so our work helps the scientific community build a large database on exposure levels in the working environment.” This means companies, regulators and stakeholders will have access to reliable information from which to base risk-assessment decisions and develop standards for occupational exposure levels for different types of ENMs.

“Thanks to our work, the ‘big picture’ is that people won’t have to be concerned about lack of information on exposure levels. This reduces uncertainty about ENM safety and fosters more innovation in nanosciences in general,” he concludes.

You can find out more about the Nanodevice project here.

Finally, the UK’s Health and Safety Executive released a guidance (I think we’d call them guidelines here in Canada) according to a Mar. 28, 2013 news item on Nanowerk (Note: A link has been removed),

The UK’s Health and Safety Executive (HSE) has released a new guidance (“Using nanomaterials at work”; pdf)that describes how to control occupational exposure to manufactured nanomaterials in the workplace. It will help you understand what you need to do to comply with the Control of Substances Hazardous to Health Regulations 2002 (COSHH) (as amended) when you work with these substances.

There’s more information about the guidance on the Using nanomaterials at work webpage where you can also find the document,

If you work with nanomaterials this guidance will help you protect your employees. If you run a medium-sized or large business, where decisions about controlling hazardous substances are more complex, you may also need professional advice. This guidance will also be useful for trade union and employee health and safety representatives.

This guidance is specifically about the manufacture and manipulation of all manufactured nanomaterials, carbon nanotubes (CNTs) and other bio-persistent high aspect ratio nanomaterials (HARNs). It has been prepared in response to emerging evidence about the toxicity of these materials.

The control principles described can be applied to all nanomaterials used in the workplace. Any differences in the approach between control of CNTs and other bio-persistent HARNs to any other type of nanomaterials are highlighted in the text.

For anyone who wants a direct link to the guidance, go here.

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Carbon nanotubes, good vibrations, and quantum computing

Monday, March 25th, 2013

Apparently carbon nanotubes can store information within their vibrations and this could have implications for quantum computing, from the Mar. 21, 2013 news release on EurekAlert,

A carbon nanotube that is clamped at both ends can be excited to oscillate. Like a guitar string, it vibrates for an amazingly long time. “One would expect that such a system would be strongly damped, and that the vibration would subside quickly,” says Simon Rips, first author of the publication. “In fact, the string vibrates more than a million times. The information is thus retained up to one second. That is long enough to work with.”

Since such a string oscillates among many physically equivalent states, the physicists resorted to a trick: an electric field in the vicinity of the nanotube ensures that two of these states can be selectively addressed. The information can then be written and read optoelectronically. “Our concept is based on available technology,” says Michael Hartmann, head of the Emmy Noether research group Quantum Optics and Quantum Dynamics at the TU Muenchen. “It could take us a step closer to the realization of a quantum computer.”

The research paper can be found here,

Quantum Information Processing with Nanomechanical Qubits
Simon Rips and Michael J. Hartmann,
Physical Review Letters, 110, 120503 (2013) DOI: 10.1103/PhysRevLett.110.120503
Link: http://prl.aps.org/abstract/PRL/v110/i12/e120503

The paper is behind a paywall.

There are two Good Vibrations songs on YouTube, one by the Beach Boys and one by Marky Mark. I decided to go with this Beach Boys version in part due to its technical description at http://youtu.be/NwrKKbaClME,

FIRST TRUE STEREO version with lead vocals properly placed in the mix. I also restored the original full length of the bridge that was edited out of the released version. An official true stereo mix of the vocal version was not made back in 1967. While there are other “stereo” versions posted, for the most part they are “fake” or poor stereo versions. I tried to make the best judicious decision on sound quality, stereo imaging and mastering while maintaining TRUE STEREO integrity given the source parts available. I hope you enjoy it!

The video,

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Shake hands with Sacha, a robot controlled by carbon nanotube transistors

Monday, March 18th, 2013

Since we use computer chips built from silicon in any number devices including robots, the announcement of a robot controlled by the first computer chip built entirely of a material other silicon bears notice. From the Mar. 15, 2013 news item on Nanowerk (Note: Links have been removed),

A group of Stanford researchers recently debuted the first robot controlled by a computer chip built entirely from carbon nanotube transistors, which many scientists predict may eventually replace silicon.

While scientists have produced simple demonstrations of working carbon nanotube circuit components in the past, the Stanford team, led by Professor of Electrical Engineering Philip Wong and Associate Professor of Electrical Engineering and Computer Science Subhasish Mitra Ph.D. ’00, was able to demonstrate an actual subsystem composed entirely of the material.

The news item was originated by a Mar. 7, 2013 article by Nikhita Obeegadoo for the Stanford Daily, where she noted,

The project was presented in the form of a robot named Sacha at the 2013 International Solid-State Circuits Conference (“Sacha, the Stanford Carbon Nanotube Controlled Handshaking Robot”), which was held in San Francisco. According to Mitra, the robot was created to demonstrate the development of a system that can function despite the errors caused by inherently imperfect nanotubes, which have posed issues for research teams working with carbon nanotubes in the past.

…

“Through several generations of technology, devices keep getting smaller and denser, and silicon will no longer be the best material for the purpose in about ten years,” Guha [Supratik Guha, director of physical sciences at IBM’s Yorktown Heights Research Center] said. “For needs that are close to atomic dimensions, carbon nanotubes have just the right shape and the right electrical behavior.”

Eric Juma on his eponymous blog offers more insight into the project in his Mar. 16, 2013 posting,

… The robot contained a carbon nanotube capacitor, a device found in many touchscreens, connected to another nanotube circuit, which turned the analog signal from the capacitor into a digital signal, which was transmitted to the microprocessor that contained CNT transistors. The microporcessor then sent a signal to a motor on the hand of the robot, which shook the person’s hand that touched the capacitors embedded in it.

This is not the first example of carbon nanotube circuitry, but it is the first example of CNTs being produced at mass for a microprocessor and circuit that were integrated. This advancement showed that it is possible to produce mass amounts of CNTs and have them integrate succesfully into a complex system. Although the size of the CNTs in this system are far from the optimal size of 10nm, it is a good starting point, and the nanotubes still can be much further refined.

Carbon nanotubes, although perfect in theory for microprocessors, present new challenges for engineers. The greatest challenge is the actual integration of CNTs into circuitry. Nanotubes often force themselves into a tangled position, which can cause circuits to fail without warning.

Juma gives a good explanation for why there is so much interest in carbon nanotubes in the field of electronics and he provides links to more information about it all. (There’s a video about carbon nanotubes and their various shapes and structures in my Mar. 15, 2013 posting about them.)

Sacha will be seen (or perhaps the work will simply be presented by Max Shulaker?) next in Switzerland at a Mar. 25, 2013 workshop (FED ’13; Functionality-Enhanced Devices Workshop) at the EPFl (École Polytechnique Fédérale de Lausanne.

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The long, the short, the straight, and the curved of them: all about carbon nanotubes

Friday, March 15th, 2013

I implied a question in my Mar. 12, 2013 post about the recent announcement from the US National Institute of Occupational Health and Safety (NIOSH) concerning a carbon nanotube toxicity study. I indicated some curiosity about the length of the multi-walled carbon nanotubes studied in this latest research. Coincidentally, Dr. Andrew Maynard (Executive Director of the University of Michigan Risk Science Center answered this implied question in his Mar. 14, 2013 posting about the study (on Andrew’s 2020 Science blog),

The carbon nanotubes in this study were inhaled multi-walled carbon nanotubes with a predominantly long, straight fiber-like morphology.  Mice were exposed at a level of 5 mg/m3 for 5 hours per day, over a 15 day period.

It’s well worth reading Andrew’s posting for the context he provides about the research and for links to further information.

For anyone who wants the short story, multi-walled carbon nanotubes (predominantly the long, straight fibre-type were used in the study) when combined with a known cancer-initiating chemical are more toxic than plain carbon nanotubes. The study has yet to be published but the results were discussed at the Society of Toxicity’s 2013 annual meeting.

Happily, he also provides this charming video (part of his Risk Bites video series) describing carbon nanotubes and their ‘infinite’ variety,

Thank you Andrew for clearing up some of my longstanding questions about carbon nanotubes.

Happy weekend to all!

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Batteries that breathe

Friday, March 8th, 2013

Researchers at the Polish Academy of Sciences Institute of Physical Chemistry have constructed a biobattery that breathes. The device could be used in medication applications as the researchers note in the Mar. 7, 2013 news release on EurekAlert,

People are increasingly taking advantage of devices supporting various functions of our bodies. Today they include cardiac pacemakers or hearing aids; tomorrow it will be contact lenses with automatically changing focal length or computer-controlled displays generating images directly in the eye. None of these devices will work if not coupled to an efficient and long-lasting power supply source. The best solution seems to be miniaturised biofuel cells consuming substances naturally occurring in human body or in its direct surrounding.

Researchers from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw developed an efficient electrode for the use in construction of biofuel cells or zinc-oxygen biobatteries. After installation in a cell, the new biocathode generates a voltage, during many hours, that is higher than that obtained in existing power sources of similar design. The most interesting is that the device is air-breathing: it works at full efficiency when it can take oxygen directly from the air.

Here’s some of the reasoning which underlies this project’s approach to the challenge of creating better batteries for implantable medical devices (from the news release),

Common batteries and rechargeable batteries are unsuitable to power implants inside the human body as they use strong bases or acids. These agents can on no account get into the body. The battery housing must be therefore absolutely tight. But in line with reducing the battery size, it must be better isolated. In extreme cases, the weight of the housing of a common, miniaturised battery would be even a few dozen times greater than the weight of the battery’s active components that generate electricity. And here biofuel cells offer an essential advantage: they do not require housing. To get electricity, it is enough to insert the electrodes into the body.

“One of the most popular experiments in electrochemistry is to make a battery by sticking appropriately selected electrodes into a potato. We are doing something similar, the difference is that we are focusing on biofuel cells and the improvement of the cathode. And, of course, to have the whole project working, we’d rather replace the potato with… a human being”, says Dr Martin Jönsson-Niedziółka (IPC PAS).

Here’s what the researchers decided to do,

In the experiments, Dr Jönsson-Niedziółka’s group uses zinc-oxygen batteries. The principle of their operation is not new. The batteries constructed in this way had been popular before the time of alkaline power sources came. “At present, many laboratories work on glucose-oxygen biofuel cells. In the best case they generate a voltage of 0.6-0.7 V. A zinc-oxygen biobattery with our cathode is able to generate 1.75 V for many hours.”, says Adrianna Złoczewska, a PhD student at the IPC PAS, whose research has been supported under the International PhD Projects Programme of the Foundation for Polish Science.

The main component of the biocathode developed at the IPC PAS is an enzyme surrounded by carbon nanotubes and encapsulated in a porous structure – a silicate matrix deposited on an oxygen permeable membrane. “Our group had been working for many years on techniques that were necessary to construct the cathode using enzymes, carbon nanotubes and silicate matrices”, stresses Prof. Marcin Opałło (IPC PAS).

An electrode so constructed is installed in a wall of a small container. To have the biofuel cell working, it is enough to pour an electrolyte (here: a solution containing hydrogen ions) and insert the zinc electrode in the electrolyte. The pores in the silicate matrix enable oxygen supply from the air and H+ ions from the solution to active centres of the enzyme, where oxygen reduction takes place. Carbon nanotubes facilitate transport of electrons from the surface of the semipermeable membrane.

A cell with the new biocathode is able to supply power with a voltage of 1.6 V, for a minimum one and a half of a week. The cell efficiency decreases with time, likely because of gradual deactivation of the enzyme on the biocathode. “Here not everything is dependent on us, but on the progress in biotechnology. The lifetime of a biofuel cells with our biocathode could be significantly prolonged, if the enzyme regeneration processes are successfully developed”, says Dr Jönsson-Niedziółka.

In the experiments carried out so far, a stack of four batteries connected in series successfully powered a lamp composed of two LEDs. Before, however, the biofuel cells based on the design developed at the IPC PAS get popularised, the researchers must solve the problem of relatively low electric power that is common to all types of biofuel cells.

I have mentioned similar projects in two previous postings, long ago. The first project was a vampire battery (a battery for implantable medical devices that powers itself with blood) mentioned in an April 3, 2009 posting. The second project was to power batteries from harvested mechanical energy from heart beats, breathing, vocal cord vibrations, and more and that was mentioned in a July 12, 2010 posting.

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15-year-old Jake Andraka and his nanotechnology-enabled test for pancreatic cancer

Thursday, March 7th, 2013

We’re led to believe that good ideas can come from anyone, anywhere, at any time and that they will be recognized as such. Every once in a while it’s nice to see evidence that there’s some truth to that notion. Jake Andraka, 15 years old, has invented a test for pancreatic cancer that seems to be mostly accurate and is cheap making it far superior to any other such test currently available. (H/T Foresight Institute, Mar.6.13 posting)

The Jan. 29, 2013 article by Damien Gayle for the UK’s Daily Mail highlights these points and goes on to describe Jake’s accomplishments at more length (there are are also videos embedded in the article),

  • Jack Andraka’s new test detects pancreatic cancer earlier than any other
  • Deadly disease currently kills 19 out of 20 within five years
  • He claims his invention could raise survival rates to ‘close to 100 per cent’

… Jack’s invention, for which he was last month awarded the grand prize of $75,000 in scholarship funds at the 2012 Intel Science Fair, means that patients now have a simple method to detect pancreatic cancer before it becomes invasive.

His novel patent-pending sensor has proved to be 28 times faster, 28 times less expensive, and over 100 times more sensitive than current tests.[emphasis mine]

…

The test works in a similar way to diabetic testing strips, with his paper strips using only a drop of blood to determine whether patients carry the mesothelin biomarker.

It is said to be over 90 per cent accurate, practically instant – and costs only 3 cents.

And what’s more, his simple test can also be used to detect ovarian and lung cancer, and it could be easily altered to detect the biomarkers of a range of other conditions.

‘What’s so cool about that is its applicability to other diseases…for example other forms of cancer, tuberculosis, HIV, environmental contaminants like E Coli, salmonella,’ Jack told Take Part.

Andraka is also profiled in a December 2012 article by Abigail Tucker for the Smithsonian Institution. It reads more like a profile for a fan magazine (in parts) than one might expect from the Smithsonian but all that’s mixed in with some science and a discussion about product availability,

It’s first period digital arts class, and the assignment is to make Photoshop monsters. Sophomore Jack Andraka considers crossing a velociraptor with a Brazilian wandering spider, while another boy grafts butterfly wings onto a rhinoceros. Meanwhile, the teacher lectures on the deranged genius of Doctor Moreau and Frankenstein, “a man who created something he didn’t take responsibility for.”

“You don’t have to do this, Jack!” somebody in back shouts.

The silver glint of a retainer: Andraka grins. Since he won the $75,000 grand prize at this past spring’s Intel International Science and Engineering Fair, one of the few freshman ever to do so, he’s become a North County High School celebrity to rival any soccer star or homecoming queen.

…

That’s exactly what Andraka may have invented: A small dipstick probe that uses just a sixth of a drop of blood appears to be much more accurate than existing approaches and takes five minutes to complete. It’s still preliminary, but drug companies are interested, and word is spreading. “I’ve gotten these Facebook messages asking, ‘Can I have the test?’” Andraka says. “I am heartbroken to say no.” [emphasis mine]

According to the Jan. 27, 2013 article by Andri Antoniades for Take Part, Andraka has been talking to companies such as LabCorp and QuestDiagnostics,

He has big plans to turn the medical community on its ear by mass marketing his work, making it widely available. He says, “Essentially what I’m envisioning here is that this could be on your shelf at your Walgreens, your Kmart. Let’s say you suspect you have a condition…you buy the test for that. And you can see immediately if you have it. Instead of your doctor being the doctor, you’re the doctor.” The teenager reports that he’s already in talks with major corporations like LabCorp and QuestDiagnostics to bring his kits to store shelves “as soon as possible,” though how long that may actually take isn’t yet known.

John Nosta’s interview with Andraka, which highlights some of the difficulties associated with science research, was published in a Feb. 1, 2013 posting on Forbes.com,

–Was your discovery easy?  Did the innovation come in a flash…then the details worked out?

I like to read a lot of journals and articles about different topics and then lie on the couch or take a walk and just let all the information settle. Then all of a sudden I can get an idea and connect some dots. Then it’s back to reading so I can fill in missing pieces. With this sensor I had put in a lot of time learning about nanoparticles for my previous research on the effects of bulk and nano metal oxides on marine and freshwater organisms. I felt that single walled carbon nano tubes were like the super heroes of material science and I wanted to work with them some more. Then when I was reading a paper about them in biology class, the teacher was explaining about antibodies. All of a sudden I made a connection and wondered what would happen if I dispersed single wall carbon nanotubes with an antibody to a protein over-expressed in pancreatic cancer. Then of course there was a lot of reading, learning and planning in front of me!

… It seemed so easy so I stalked the internet and found the names and professional emails of lots of professors in my area who were working on pancreatic cancer. Then I just figured I’d sit back and wait for the acceptances to roll in! Week after week I’d receive endless rejections. The most helpful one was actually from a researcher who took the time to point out every flaw and reason why my project was impossible. I began to despair!

… Finally, after 199 rejections, I received one email from Dr Maitra at Johns Hopkins School of Medicine. He invited me to come for a meeting. My mom drove me there and dropped me off. It was pretty exhilarating yet scary to walk in to the interview! Luckily I was really prepared and even had the cost and catalog numbers of the material I needed. He said it was like reading a grant proposal. I still had a great deal of basic lab routine to learn and I appreciate the time and patience of both Dr Maitra [Anirban Maitra] and Dr Chenna [V. Chenna], the post- doc who supported me.

There’s a brief description of Andraka’s test in an article (published June 16, 2012 online) by Devin Powell for Science News, 181 (12),

Searching for a better detector for mesothelin, Andraka coated paper with tiny tubes of atom-thick carbon. Antibodies stuck to the carbon nanotubes can grab the telltale protein and spread the tubes apart. The carbon’s resistance to the flow of electricity drops measurably as more protein attaches. Tests of the paper using blood samples from 100 people with cancer at different stages of the disease identified the presence of cancer every time, Andraka reported.

It’s quite a story on any number of levels. It’s not just Andraka’s age. There’s the simplicity of the idea, the difficulty of getting anyone to pay attention (199 rejections, that number seems suspiciously poetic), and what was undoubtedly a lot of painstaking, boring, hard work. Finally, the reference to a patent seems very much in the tenor of the times. I wish Andraka good luck with his work and I hope the test is available soon.

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