How To Mimic Neural Tissue

U.S. Army-funded researchers at Brandeis University have discovered a process for engineering next-generation soft materials with embedded chemical networks that mimic the behavior of neural tissue. The breakthrough material may lead to autonomous soft robotics, dual sensors and actuators for soft exoskeletons, or artificial skins.

The research lays the foundations for futuristic soft active matter with highly distributed and tightly integrated sensing, actuation, computation and control, said Dr. Samuel Stanton, manager of the Complex and Dynamics Systems Program within the Engineering Sciences Directorate at the Army Research Office (ARO) , an element of the U.S. Army Research Laboratory, located at Research Triangle Park in Durham, North Carolina.

ARO funds research to initiate scientific and far-reaching technological discoveries in extramural organizations, educational institutions, nonprofit organizations and private industry that may make future American Soldiers stronger and safer.

The research team, led by Professor of Physics Dr. Seth Fraden of Brandeis University, drew inspiration from the mesmerizing sinuous motion of a swimming blue eel and puzzlingly large gap between how natural systems move and the lack of such coordinated and smooth movement in artificial systems.

New breakthrough material could lead to future autonomous soft robotics, dual sensors and actuators for soft exoskeletons, or artificial skins.

Our research interests lie squarely in the intersection of physics, chemistry, biology and materials science,” Fraden said. “Our lab is interdisciplinary, but we are also involved in several multi-investigator projects.

Fraden’s work sought to answer key questions, such as why is there such a void between the animate and inanimate that we never confuse the two, and if engineers could create materials with similar attributes to living organisms, but constructed from inanimate objects, can we do so using only chemicals and eschew use of motors and electronics? Looking deeper, Fraden studied how a type of neural network present in the eel, named the Central Pattern Generator (CPG), produces waves of chemical pulses that propagate down the eel’s spine to rhythmically drive swimming muscles.

Fraden’s lab approached the challenge of engineering a material mimicking the generator by first constructing a control device that produces the same neural activation patterns biologists have observed. There, they created a control system that runs on chemical power, as is done in biology, without resorting to any computer or electromechanical devices, which are the hallmarks of manmade, hard robotic technology.

A breakthrough was made when Fraden and his team realized that the same CPG dynamics could be captured on a non-biological platform if they used a well-known oscillating chemical process known as the Belousov–Zhabotinsky reaction. The lab developed state-of-the-art fabrication techniques for soft materials engineering artificial chemical networks at the nanoscale that, altogether, would be capable of producing a wide variety of patterns. Their resulting robust chemical networks produced distributed dynamic patterns identical to the eel’s Central Pattern Generator.

Fraden noted that “the engineering principles they identified are general and can be applied to design a whole range of other Central Pattern Generators, such as those responsible for other autonomous functions, such as the gait of a horse, for example, walk, canter, trot and gallop.”


Sniffing Device Smells 17 Diseases On A Person’s Breath

Israeli scientists have told an audience of peers in London how they have developed a “cancer-sniffing nose” using nanotechnology to detect the disease early.The electronicnose’ he developed can smell 17 diseases on a person’s breath, including Alzheimer’s, Parkinson’s, tuberculous, diabetes and lung cancer. The non-intrusive medical device, which works by identifying as disease’s bio-markers, has attracted the attention of billionaires such as Bill and Melinda Gates, whose foundation focuses on the diagnostics of diseases.

Every disease has a unique signature – a ‘breath print,’” Hossam Haick, an Israeli researcher, explained. “The challenge is to bring the best science we have proven into reality by developing a smaller device that captures all the components of a disease appearing in the breath.”

Professor Hossam  Haick works at the Department of Chemical Engineering and the Russell Berrie Nanotechnology Institute at the Technion in Israel and is an expert in the field of nanotechnology and non-invasive disease diagnosis.

The University said the latest advances in his research mean that it has the potential to identify diseases though sensors in mobile phones and wearable technology, and with more analysis and data it may even be able to predict cancer in the future.


Nanotechnology: A Treasure Trove With 1000 New 2D Materials

2D materials, which consist of a few layers of atoms, may well be the future of nanotechnology. They offer potential new applications and could be used in small, higher-performance and more energy-efficient devices. 2D materials were first discovered almost 15 years ago, but only a few dozen of them have been synthesized so far. Now, thanks to an approach developed by researchers from EPFL‘s Theory and Simulation of Materials Laboratory (THEOS) and from NCCR-MARVEL for Computational Design and Discovey of Novel Materials, many more promising 2D materials may now be identified. Their work was recently published in the journal Nature Nanotechnology, and even got a mention on the cover page.

The first 2D material to be isolated was graphene, in 2004, earning the researchers who discovered it a Nobel Prize in 2010. This marked the start of a whole new era in electronics, as graphene is light, transparent and resilient and, above all, a good conductor of electricity. It paved the way to new applications in numerous fields such as photovoltaics and optoelectronics.

A team from EPFL (Ecole Polytechnique Fédérale de Lausanne) and NCCR Marvel in Switzerland has identified more than 1,000 materials with a particularly interesting 2D structure. Their research, which made the cover page of Nature Nanotechnology, paves the way for groundbreaking technological applications.

To find other materials with similar properties, we focused on the feasibility of exfoliation,” explains Nicolas Mounet, a researcher in the THEOS lab and lead author of the study. “But instead of placing adhesive strips on graphite to see if the layers peeled off, like the Nobel Prize winners did, we used a digital method.”


Effective Insertion Of DNA Molecules Into Cells For Gene Therapies

For years, researchers have attempted to harness the full potential of gene therapy, a technique that inserts genes into a patient’s cells to treat aggressive diseases such as cancer. But getting engineered DNA molecules into cells is not an easy task.

J. Mark Meacham, assistant professor of mechanical engineering & materials science at Washington University in St. Louis, leads a team of researchers that has developed a method enabling effective insertion of large molecules — such as DNA, RNA and proteins into cells and propels them into the cell nucleus. By combining a technique known as Acoustic Shear Poration (ASP) with electrophoresis, the approach uses ultrasound waves and focused mechanical force to create nanoscale holes, or pores, in the cell membrane that are big enough for large macromolecules or nanoparticles to pass into the cell’s interior.

Operation of the acoustic shear poration (ASP) device in Meacham’s lab

The researchers wrote that so far, ASP has achieved greater than 75 percent delivery efficiency of macromolecules. DNA insertion, or transfection, which is of most interest in gene therapy, is significantly more challenging. Yet the combined application of mechanical and electrical forces pioneered by Meacham and colleagues yields roughly 100 percent improvement in transfection versus pure mechanoporation. Results of the research are published in Scientific Reports.


Flexible, Low-Cost, Water-Repellent Gaphene Circuits

New graphene printing technology can produce electronic circuits that are low-cost, flexible, highly conductive and water repellent. The nanotechnology “would lend enormous value to self-cleaning wearable/washable electronics that are resistant to stains, or ice and biofilm formation,” according to a recent paper describing the discovery.

“We’re taking low-cost, inkjet-printed graphene and tuning it with a laser to make functional materials,” said Jonathan Claussen, an Iowa State University assistant professor of mechanical engineering, an associate of the U.S. Department of Energy’s and the corresponding author of the paper recently featured on the cover of the journal Nanoscale. The paper describes how Claussen and the nanoengineers in his research group use to create electric circuits on flexible materials. In this case, the ink is flakes of graphene – the wonder material can be a great conductor of electricity and heat, plus it’s strong, stable and biocompatible.

And now they’ve found another application of their laser processing technology: taking graphene-printed circuits that can hold water droplets (they’re hydrophilic) and turning them into circuits that repel water (they’re superhydrophobic).

We’re micro-patterning the surface of the inkjet-printed graphene,” Claussen said. “The laser aligns the graphene flakes vertically – like little pyramids stacking up. And that’s what induces the hydrophobicity.” Claussen said the energy density of the laser processing can be adjusted to tune the degree of hydrophobicity and conductivity of the printed graphene circuits. And that opens up all kinds of possibilities for new electronics and sensors, according to the paper. “One of the things we’d be interested in developing is anti-biofouling materials,” said Loreen Stromberg, a paper co-author and an Iowa State postdoctoral research associate in mechanical engineering and for the Virtual Reality Applications Center. “This could eliminate the buildup of biological materials on the surface that would inhibit the optimal performance of devices such as chemical or biological sensors.”

The technology could also have applications in flexible electronics, washable sensors in textiles, microfluidic technologies, drag reduction, de-icing, electrochemical sensors and technology that uses graphene structures and electrical simulation to produce stem cells for nerve regeneration. The researchers wrote that further studies should be done to better understand how the nano– and microsurfaces of the printed graphene creates the water-repelling capabilities. .

The Iowa State University Research Foundation is working to patent the technology and has optioned it to an Ames-based startup, NanoSpy Inc., for possible commercialization. NanoSpy, located at the Iowa State University Research Park, is developing sensors to detect salmonella and other pathogens in food processing plants. Claussen and Stromberg are part of the company.


Efficient, Low-Cost Catalyst To Produce Hydrogen

A nanostructured composite material developed at UC Santa Cruz has shown impressive performance as a catalyst for the electrochemical splitting of water to produce hydrogen. An efficient, low-cost catalyst is essential for realizing the promise of hydrogen as a clean, environmentally friendly fuel.

Researchers led by Shaowei Chen, professor of chemistry and biochemistry at UC Santa Cruz, have been investigating the use of carbon-based nanostructured materials as catalysts for the reaction that generates hydrogen from water. In one recent study, they obtained good results by incorporating ruthenium ions into a sheet-like nanostructure composed of carbon nitride. Performance was further improved by combining the ruthenium-doped carbon nitride with graphene, a sheet-like form of carbon, to form a layered composite.

The bonding chemistry of ruthenium with nitrogen in these nanostructured materials plays a key role in the high catalytic performance,” Chen said. “We also showed that the stability of the catalyst is very good.”

Currently, the most efficient catalysts for the electrochemical reaction that generates hydrogen from water are based on platinum, which is scarce and expensive. Carbon-based materials have shown promise, but their performance has not come close to that of platinum-based catalysts.

In the new composite material developed by Chen’s lab, the ruthenium ions embedded in the carbon nitride nanosheets change the distribution of electrons in the matrix, creating more active sites for the binding of protons to generate hydrogen. Adding graphene to the structure further enhances the redistribution of electrons.

The new findings were published in ChemSusChem.


Memristors Retain Data 10 Years Without Power

The internet of things ( IoT) is coming, that much we know. But still it won’t; not until we have components and chips that can handle the explosion of data that comes with IoT. In 2020, there will already be 50 billion industrial internet sensors in place all around us. A single autonomous device – a smart watch, a cleaning robot, or a driverless car – can produce gigabytes of data each day, whereas an airbus may have over 10 000 sensors in one wing alone.

Two hurdles need to be overcome. First, current transistors in computer chips must be miniaturized to the size of only few nanometres; the problem is they won’t work anymore then. Second, analysing and storing unprecedented amounts of data will require equally huge amounts of energy. Sayani Majumdar, Academy Fellow at Aalto University (Finland), along with her colleagues, is designing technology to tackle both issues.

Majumdar has with her colleagues designed and fabricated the basic building blocks of future components in what are called “neuromorphiccomputers inspired by the human brain. It’s a field of research on which the largest ICT companies in the world and also the EU are investing heavily. Still, no one has yet come up with a nano-scale hardware architecture that could be scaled to industrial manufacture and use.

The probe-station device (the full instrument, left, and a closer view of the device connection, right) which measures the electrical responses of the basic components for computers mimicking the human brain. The tunnel junctions are on a thin film on the substrate plate.

The technology and design of neuromorphic computing is advancing more rapidly than its rival revolution, quantum computing. There is already wide speculation both in academia and company R&D about ways to inscribe heavy computing capabilities in the hardware of smart phones, tablets and laptops. The key is to achieve the extreme energy-efficiency of a biological brain and mimic the way neural networks process information through electric impulses,” explains Majumdar.

In their recent article in Advanced Functional Materials, Majumdar and her team show how they have fabricated a new breed of “ferroelectric tunnel junctions”, that is, few-nanometre-thick ferroelectric thin films sandwiched between two electrodes. They have abilities beyond existing technologies and bode well for energy-efficient and stable neuromorphic computing.

The junctions work in low voltages of less than five volts and with a variety of electrode materials – including silicon used in chips in most of our electronics. They also can retain data for more than 10 years without power and be manufactured in normal conditions.

Tunnel junctions have up to this point mostly been made of metal oxides and require 700 degree Celsius temperatures and high vacuums to manufacture. Ferroelectric materials also contain lead which makes them – and all our computers – a serious environmental hazard.

Our junctions are made out of organic hydro-carbon materials and they would reduce the amount of toxic heavy metal waste in electronics. We can also make thousands of junctions a day in room temperature without them suffering from the water or oxygen in the air”, explains Majumdar.

What makes ferroelectric thin film components great for neuromorphic computers is their ability to switch between not only binary states – 0 and 1 – but a large number of intermediate states as well. This allows them to ‘memoriseinformation not unlike the brain: to store it for a long time with minute amounts of energy and to retain the information they have once received – even after being switched off and on again.

We are no longer talking of transistors, but ‘memristors’. They are ideal for computation similar to that in biological brains.  Take for example the Mars 2020 Rover about to go chart the composition of another planet. For the Rover to work and process data on its own using only a single solar panel as an energy source, the unsupervised algorithms in it will need to use an artificial brain in the hardware.

What we are striving for now, is to integrate millions of our tunnel junction memristors into a network on a one square centimetre area. We can expect to pack so many in such a small space because we have now achieved a record-high difference in the current between on and off-states in the junctions and that provides functional stability. The memristors could then perform complex tasks like image and pattern recognition and make decisions autonomously,” says Majumdar.


How Nanotechnology Can Help Heal Hearts

Nanotechnology is especially suited to medicine because nature operates at not even a micro, but a nano scale synapses, the extracellular spaces between neurons that exchange massive amounts of information per second are approximately only 20-40 nanometres (nm) wide. The typical largest coronary artery, which supplies oxygen-rich blood to the heart, barely measures an inch in diameter.

Nanotechnology works with this natural nanoscale to deliver better healthcare results with fewer risks and side effects in a shorter span of time. It uses finer instruments, minimally invasive procedures and more efficient drug delivery systems to unblock blood vessels and repair tissues. This aspect of nanotechnology is especially useful and can reduce the risks associated with many invasive procedures, including cardiac care protocols.

Angioplasty is a procedure to open narrowed or blocked coronary arteries, which supply blood to the heart. During an angioplasty, a balloon catheter is guided into the affected artery; the balloon may be ‘blown up’ a few times to widen the diameter of the artery. Often a coronary artery stent, a small, metal mesh tube that expands inside the artery, is placed during or immediately after angioplasty to help prevent the artery from closing up again. A drug-eluting stent, now the norm, has medicine embedded in it that helps prevent the artery from closing in the long-term.

So far, so good. But this is where we run into a hiccup.  One of the biggest problems with current drug-eluting stents is Paclitaxel, the very drug they carry. Clinical trials show toxicity associated with Paclitaxel and increased chances of thrombosis, a dangerous event linked with heart attacks and strokes. Cardiologists remain conflicted over the use of Paclitaxel. A possible solution to Paclitaxel could be an alternate, safer drug, which is small enough at the molecular level to be bioavailable and can also be introduced in the artery in a short span of 35-40 seconds. Keep the stent in the artery any longer than this razor-thin span and you risk complications. Sirolimous is one such drug, but the biggest problem with Sirolimous is that it is slow on the uptake.

It took years of research by a dedicated core team of doctors, surgeons, pharmacists and chemists to finally put together the puzzle. And when all the pieces locked in place, the answer was perfect in its simplicity – a nanotechnology-enabled polymer-free drug-eluting stent system, especially adapted to carry Sirolimous, a far safer and hypoallergenic drug than Paclitaxel.


How To Turn Nitrates Into Water And Air

Engineers at Rice University’s Nanotechnology Enabled Water Treatment (NEWT) Center have found a catalyst that cleans toxic nitrates from drinking water by converting them into air and water.

Nitrates come mainly from agricultural runoff, which affects farming communities all over the world,” said Rice chemical engineer Michael Wong, the lead scientist on the study. “Nitrates are both an environmental problem and health problem because they’re toxic. There are ion-exchange filters that can remove them from water, but these need to be flushed every few months to reuse them, and when that happens, the flushed water just returns a concentrated dose of nitrates right back into the water supply.”

Wong’s lab specializes in developing nanoparticle-based catalysts, submicroscopic bits of metal that speed up chemical reactions. In 2013, his group showed that tiny gold spheres dotted with specks of palladium could break apart nitrites, the more toxic chemical cousins of nitrates.

Nitrates are molecules that have one nitrogen atom and three oxygen atoms,” Wong explained. “Nitrates turn into nitrites if they lose an oxygen, but nitrites are even more toxic than nitrates, so you don’t want to stop with nitrites. Moreover, nitrates are the more prevalent problem. Ultimately, the best way to remove nitrates is a catalytic process that breaks them completely apart into nitrogen and oxygen, or in our case, nitrogen and water because we add a little hydrogen, he said”. “More than 75 percent of Earth’s atmosphere is gaseous nitrogen, so we’re really turning nitrates into air and water.

Nitrates are toxic to infants and pregnant women and may also be carcinogenic. Nitrate pollution is common in agricultural communities, especially in the U.S. Corn Belt and California’s Central Valley, where fertilizers are heavily used, and some studies have shown that nitrate pollution is on the rise due to changing land-use patterns.

Both nitrates and nitrites are regulated by theEnvironmental Protection Agency, which sets allowable limits for safe drinking water. In communities with polluted wells and lakes, that typically means pretreating drinking water with ion-exchange resins that trap and remove nitrates and nitrites without destroying them.

The research is available online in the American Chemical Society journal ACS Catalysis.


Nano-based Air Purifier Destroys Pollutants

Molekule, a San Francisco-based startup with a sleekly designed molecular air purifier started as an immigrant dream twenty years ago and ended up being named one of Time’s top 25 inventions of 2017. The inventor Yogi Goswami came up with the idea when his baby son Dilip started having a hard time breathing the air around him. Dilip suffered from severe asthma but no air purifier at the time seemed to work well enough to clean up indoor pollutants. Traditional HEPA filters simply trap a few pollutants but they don’t grab everything and they don’t break them down before releasing them back into the air.

So, Goswami the elder came up with a filter technology that could both suck up things like allergens, mold and bacteria and particles up to one-thousand times smaller than what a HEPA filter can catch using photo electrochemical oxidation (PECO) and nanotechnology to destroy the pollutants on a molecular level and eliminate the full spectrum of indoor air pollutants. The result? Clean, breathable air that even the most sensitive person can handle. Dilip and his sister Jaya Goswami patented the tech and founded Molekule to bring their father’s invention to the rest of us.

The company now ships a stylish $800, two-foot-tall cylinder with the patented filter inside. Sure, it’s a lot pricier than most filters out there but the company also offers financing at $67 a month. It was also instrumental in helping folks breathe during the Northern California wildfires this fall. Jaya mentioned Molekule’s inventory was completely depleted during that time and that the company couldn’t ship fast enough — the product is still backordered till January 3rd, 2018. So far Molekule has brought in just over $13 million in venture funding to keep it going.


Nobel Prize Nanotechnologist Launches His Own Anti-Aging Cosmetic Line

In 2016, J. Fraser Stoddart won the Nobel Prize in Chemistry for his part in designing a molecular machine. Now as chief technology officer and cofounder of nanotechnology firm PanaceaNano, he has introduced the “Noble” line of antiaging cosmetics, including a $524 formula described as an “anti-wrinkle repair” night cream. The firm says the cream contains Nobel Prize-winning “organic nano-cubes” loaded with ingredients that reverse skin damage and reduce the appearance of wrinkles. Other prize-winning chemists have founded companies, but Stoddart’s backing of the antiaging cosmetic line takes the promotion of a new company by an award-winning scientist to the next level.

The nano-cubes are made of carbohydrate molecules known as cyclodextrins. The cubes, of various sizes and shapes, release ingredients such as vitamins and peptides onto the skin “at predefined times with molecular precision,” according to the Noble skin care website. PanaceaNano cofounder Youssry Botros, former nanotechnology research director at Intel, contends that the metering technology makes the product line “far superior to comparable products in the market today.” However, the nanocubes aren’t molecular machines, for which Stoddart won his Nobel prize.

While acknowledging the product line trades on his Nobel prize, Stoddart points out that “we’re not spelling our product name, Noble, the way the Swedish Nobel Foundation does.Ethicist Michael Kalichman has a different perspective. Use of the word Noble, even though spelled differently than the prize, is “unseemly but not illegal,” he says. Kalichman, who is director of the Research Ethics Program at the University of California, San Diego, adds, “If his goal is to make money, this may work. But if his goal is to retain credibility and pursue other more laudable goals, maybe he should stay focused on those goals.”

Botros says PanaceaNano is also developing nanotechnology materials for markets including hydrogen storage, flexible batteries, and molecular memory based on technology from Stoddart’s lab and licensed from Northwestern University. But PanaceaNano chose to make its first commercial product a line of cosmetics because of the high margins and the ease of market entry.


DNA Origami, The New Revolution To Come For Nanotechnology

For the past few decades, some scientists have known the shape of things to come in nanotechnology is tied to the molecule of life, DNA. This burgeoning field is called “DNA origami.” The moniker is borrowed from the art of conjuring up birds, flowers and other shapes by imaginatively folding a single sheet of paper. Similarly, DNA origami scientists are dreaming up a variety of shapes — at a scale one thousand times smaller than a human hair — that they hope will one day revolutionize computing, electronics and medicine. Now, a team of Arizona State University and Harvard scientists has invented a major new advance in DNA nanotechnology. Dubbed “single-stranded origami” (ssOrigami), their new strategy uses one long noodle-like strand of DNA, or its chemical cousin RNA, that can self-fold — without even a single knot — into the largest, most complex structures to date. And the strands forming these structures can be made inside living cells or using enzymes in a test tube, allowing scientists the potential to plug-and-play with new designs and functions for nanomedicine: picture tiny nanobots playing doctor and delivering drugs within cells at the site of injury.

A DNA origami with an emoji-like smiley face

I think this is an exciting breakthrough, and a great opportunity for synthetic biology as well,” said Hao Yan, a co-inventor of the technology, director of the ASU Biodesign Institute’s Center for Molecular Design and Biomimetics, and the Milton Glick Professor in the School of Molecular Sciences.

We are always inspired by nature’s designs to make information-carrying molecules that can self-fold into the nanoscale shapes we want to make,” he said.

As proof of concept, they’ve pushed the envelope to make 18 shapes, including emoji-like smiley faces, hearts and triangles, that significantly expand the design studio space and material scalability for so-called, “bottom-upnanotechnology.