Tag Archives: Technion-Israel Institute of Technology

Therapeutic nanoparticles for agricultural crops

Nanoscale drug delivery systems developed by the biomedical community may prove useful to farmers. The Canadian Broadcasting Corporation (CBC) featured the story in a May 26, 2018 online news item (with audio file; Note: A link has been removed),

Thanks to a fortuitous conversation between an Israeli chemical engineer who works on medical nanotechnology and his farmer friend, there’s a new way to deliver nourishment to nutrient-starved crops.

Avi Schroeder, the chemical engineer and cancer researcher from Technion — Israel Institute of Technology asked his friend what are the major problems facing agriculture today. “He said, ‘You know Avi, one of the major issues we’re facing is that in some of the crops we try to grow, we actually have a lack of nutrients. And then we end up not growing those crops even though they’re very valuable or very important crops.'”

This problem is only going to become more acute in many regions of the world as global population approaches eight billion people.

“Feeding them with healthy food and nutritious food is becoming a major limiting factor. And … the land we can actually grow crops on are also becoming smaller and smaller in every country because people need to build houses too. So what we want is to get actually more crops per hectare.”

The way farmers currently deliver nutrients to malnourished agricultural crops is very inefficient. Much of what is added to the leaves of the plant is wasted. Most of it washes away or isn’t taken up by the plants.

If plants don’t get the nutrients they need, their leaves start to yellow, their growth becomes stunted and they don’t produce as much food as nutrient-rich crops.

“We work primarily in the field of medicine,” says Schroeder. “What we do many times is we’ll load minuscule doses of medicine into nanoparticles — we’ll inject them into the patient. And those nanoparticles will actually be able to detect the disease site inside the body. That sounded very, very similar to the problem the farmers were actually facing — how do you get a medicine into a crop or a nutrient into a crop and get it to the right region within the crop where it’s actually necessary.”

The nanoparticles Schroeder developed are tiny packages that can deliver nutrients — any nutrients — that are placed inside.

A June 6, 2018 news item on Nanowerk offers a few more details,

An innovative technology developed at the Technion [Israel Institute of Technology] could lead to significant increases in agricultural yields. Using a nanometric transport platform on plants that was previously utilized for targeted drug delivery, researchers increased the penetration rate of nutrients into the plants, from 1% to approximately 33%.

A May 27,2018 Technion press release, which originated the news item, fleshes out the details,

The technology exploits nanoscale delivery platforms which until now were used to transport drugs to specific targets in the patient’s body. The work was published in Scientific Reports and will be presented in Nature Press.

The use of the nanotechnology for targeted drug delivery has been the focus of research activity conducted at the Laboratory for Targeted Drug Delivery and Personalized Medicine Technologies at the Wolfson Faculty of Chemical Engineering. The present research repurposes this technology for agricultural use; and is being pursued by laboratory director Prof. Avi Schroeder and graduate student Avishai Karny.

“The constant growth in the world population demands more efficient agricultural technologies, which will produce greater supplies of healthier foods and reduce environmental damage,” said Prof. Schroeder. “The present work provides a new means of delivering essential nutrients without harming the environment.”

The researchers loaded the nutrients into liposomes which are small spheres generated in the laboratory, comprised of a fatty outer layer enveloping the required nutrients. The particles are stable in the plant’s aqueous environment and can penetrate the cells. In addition, the Technion researchers can ‘program’ them to disintegrate and release the load at precisely the location and time of interest, namely, in the roots and leaves. Disintegration occurs in acidic environments or in response to an external signal, such as light waves or heat. The molecules comprising the particles are derived from soy plants and are therefore approved and safe for consumption by both humans and animals.

In the present experiment, the researchers used 100-nanometer liposomes to deliver the nutrients iron and magnesium into both young and adult tomato crops. They demonstrated that the liposomes, which were sprayed in the form of a solution onto the leaves, penetrated the leaves and reached other leaves and roots. Only when reaching the root cells did they disintegrate and release the nutrients. As said, the technology greatly increased the nutrient penetration rate.

In addition to demonstrating the effectivity of this approach as compared to the standard spray method, the researchers also assessed the regulatory limitations associated with the spread of volatile particles.

”Our engineered liposomes are only stable within a short spraying range of up to 2 meters,” explained Prof. Schroeder. “If they travel in the air beyond that distance, they break down into safe materials (phospholipids). We hope that the success of this study will expand the research and development of similar agricultural products, to increase the yield and quality of food crops.”

This is an illustration of the work,

Each liposome (light blue bubble) was loaded with iron and magnesium particles. The liposomes sprayed on the leaves, penetrated and then spread throughout the various parts of the plant and released their load within the cells. Courtesy: Technion

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

Therapeutic nanoparticles penetrate leaves and deliver nutrients to agricultural crops by Avishai Karny, Assaf Zinger, Ashima Kajal, Janna Shainsky-Roitman, & Avi Schroeder. Scientific Reportsvolume 8, Article number: 7589 (2018) DOI: https://doi.org/10.1038/s41598-018-25197-y Published 17 May 2018

This paper is open access.

Extinction of Experience (EOE)

‘Extinction of experience’ is a bit of an attention getter isn’t it? Well, it worked for me when I first saw it and it seems particularly apt after putting together my August 9, 2018 posting about the 2018 SIGGRAPH conference, in particular, the ‘Previews’ where I featured a synthetic sound project. Here’s a little more about EOE from a July 3, 2018 news item on phys.org,

Opportunities for people to interact with nature have declined over the past century, as most people now live in urban areas and spend much of their time indoors. And while adults are not only experiencing nature less, they are also less likely to take their children outdoors and shape their attitudes toward nature, creating a negative cycle. In 1978, ecologist Robert Pyle coined the phrase “extinction of experience” (EOE) to describe this alienation from nature, and argued that this process is one of the greatest causes of the biodiversity crisis. Four decades later, the question arises: How can we break the cycle and begin to reverse EOE?

A July 3, 2018 North Carolina Museum of Natural Sciences news release, which originated the news item, delves further,

In citizen science programs, people participate in real research, helping scientists conduct studies on local, regional and even global scales. In a study released today, researchers from the North Carolina Museum of Natural Sciences, North Carolina State University, Rutgers University, and the Technion-Israel Institute of Technology propose nature-based citizen science as a means to reconnect people to nature. For people to take the next step and develop a desire to preserve nature, they need to not only go outdoors or learn about nature, but to develop emotional connections to and empathy for nature. Because citizen science programs usually involve data collection, they encourage participants to search for, observe and investigate natural elements around them. According to co-author Caren Cooper, assistant head of the Biodiversity Lab at the N.C. Museum of Natural Sciences, “Nature-based citizen science provides a structure and purpose that might help people notice nature around them and appreciate it in their daily lives.”

To search for evidence of these patterns across programs and the ability of citizen science to reach non-scientific audiences, the researchers studied the participants of citizen science programs. They reviewed 975 papers, analyzed results from studies that included participants’ motivations and/or outcomes in nature-oriented programs, and found that nature-based citizen science fosters cognitive and emotional aspects of experiences in nature, giving it the potential to reverse EOE.

The eMammal citizen science programs offer children opportunities to use technology to observe nature in new ways. Photo: Matt Zeher. The eMammal citizen science programs offer children opportunities to use technology to observe nature in new ways. Photo: Matt Zeher.

The N.C. Museum of Natural Sciences’ Stephanie Schuttler, lead author on the study and scientist on the eMammal citizen science camera trapping program, saw anecdotal evidence of this reversal through her work incorporating camera trap research into K-12 classrooms. “Teachers would tell me how excited and surprised students were about the wildlife in their school yards,” Schuttler says. “They had no idea their campus flourished with coyotes, foxes and deer.” The study Schuttler headed shows citizen science increased participants’ knowledge, skills, interest in and curiosity about nature, and even produced positive behavioral changes. For example, one study revealed that participants in the Garden Butterfly Watch program changed gardening practices to make their yards more hospitable to wildlife. Another study found that participants in the Coastal Observation and Seabird Survey Team program started cleaning up beaches during surveys, even though this was never suggested by the facilitators.

While these results are promising, the EOE study also revealed that this work has only just begun and that most programs do not reach audiences who are not already engaged in science or nature. Only 26 of the 975 papers evaluated participants’ motivations and/or outcomes, and only one of these papers studied children, the most important demographic in reversing EOE. “Many studies were full of amazing stories on how citizen science awakened participants to the nature around them, however, most did not study outcomes,” Schuttler notes. “To fully evaluate the ability for nature-based citizen science to affect people, we encourage citizen science programs to formally study their participants and not just study the system in question.”

Additionally, most citizen science programs attracted or even recruited environmentally mindful participants who likely already spend more time outside than the average person. “If we really want to reconnect people to nature, we need to preach beyond the choir, and attract people who are not already interested in science and/or nature,” Schuttler adds. And as co-author Assaf Shwartz of Technion-Israel Institute of Technology asserts, “The best way to avert the extinction of experience is to create meaningful experiences of nature in the places where we all live and work – cities. Participating in citizen science is an excellent way to achieve this goal, as participation can enhance the sense of commitment people have to protect nature.”

Luckily, some other factors appear to influence participants’ involvement in citizen science. Desire for wellbeing, stewardship and community may provide a gateway for people to participate, an important first step in connecting people to nature. Though nature-based citizen science programs provide opportunities for people to interact with nature, further research on the mechanisms that drive this relationship is needed to strengthen our understanding of various outcomes of citizen science.

And, I because I love dragonflies,

Nature-based citizen science programs, like Dragonfly Pond Watch, offer participants opportunities to observe nature more closely. Credit: Lea Shell.

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

Bridging the nature gap: can citizen science reverse the extinction of experience? by Stephanie G Schuttler, Amanda E Sorensen, Rebecca C Jordan, Caren Cooper, Assaf Shwartz. Frontiers in Ecology and the Environment. DOI: https://doi.org/10.1002/fee.1826 First published: 03 July 2018

This paper is behind a paywall.

Sniffing out disease (Na-Nose)

The ‘artificial nose’ is not a newcomer to this blog. The most recent post prior to this is a March 15, 2016 piece about Disney using an artificial nose for art conservation. Today’s (Jan. 9, 2016) piece concerns itself with work from Israel and ‘sniffing out’ disease, according to a Dec. 30, 2016 news item in Sputnik News,

A team from the Israel Institute of Technology has developed a device that from a single breath can identify diseases such as multiple forms of cancer, Parkinson’s disease, and multiple sclerosis. While the machine is still in the experimental stages, it has a high degree of promise for use in non-invasive diagnoses of serious illnesses.

The international team demonstrated that a medical theory first proposed by the Greek physician Hippocrates some 2400 years ago is true, certain diseases leave a “breathprint” on the exhalations of those afflicted. The researchers created a prototype for a machine that can pick up on those diseases using the outgoing breath of a patient. The machine, called the Na-Nose, tests breath samples for the presence of trace amounts of chemicals that are indicative of 17 different illnesses.

A Dec. 22, 2016 Technion Israel Institute of Technology press release offers more detail about the work,

An international team of 56 researchers in five countries has confirmed a hypothesis first proposed by the ancient Greeks – that different diseases are characterized by different “chemical signatures” identifiable in breath samples. …

Diagnostic techniques based on breath samples have been demonstrated in the past, but until now, there has not been scientific proof of the hypothesis that different and unrelated diseases are characterized by distinct chemical breath signatures. And technologies developed to date for this type of diagnosis have been limited to detecting a small number of clinical disorders, without differentiation between unrelated diseases.

The study of more than 1,400 patients included 17 different and unrelated diseases: lung cancer, colorectal cancer, head and neck cancer, ovarian cancer, bladder cancer, prostate cancer, kidney cancer, stomach cancer, Crohn’s disease, ulcerative colitis, irritable bowel syndrome, Parkinson’s disease (two types), multiple sclerosis, pulmonary hypertension, preeclampsia and chronic kidney disease. Samples were collected between January 2011 and June 2014 from in 14 departments at 9 medical centers in 5 countries: Israel, France, the USA, Latvia and China.

The researchers tested the chemical composition of the breath samples using an accepted analytical method (mass spectrometry), which enabled accurate quantitative detection of the chemical compounds they contained. 13 chemical components were identified, in different compositions, in all 17 of the diseases.

According to Prof. Haick, “each of these diseases is characterized by a unique fingerprint, meaning a different composition of these 13 chemical components.  Just as each of us has a unique fingerprint that distinguishes us from others, each disease has a chemical signature that distinguishes it from other diseases and from a normal state of health. These odor signatures are what enables us to identify the diseases using the technology that we developed.”

With a new technology called “artificially intelligent nanoarray,” developed by Prof. Haick, the researchers were able to corroborate the clinical efficacy of the diagnostic technology. The array enables fast and inexpensive diagnosis and classification of diseases, based on “smelling” the patient’s breath, and using artificial intelligence to analyze the data obtained from the sensors. Some of the sensors are based on layers of gold nanoscale particles and others contain a random network of carbon nanotubes coated with an organic layer for sensing and identification purposes.

The study also assessed the efficiency of the artificially intelligent nanoarray in detecting and classifying various diseases using breath signatures. To verify the reliability of the system, the team also examined the effect of various factors (such as gender, age, smoking habits and geographic location) on the sample composition, and found their effect to be negligible, and without impairment on the array’s sensitivity.

“Each of the sensors responds to a wide range of exhalation components,” explain Prof. Haick and his previous Ph.D student, Dr. Morad Nakhleh, “and integration of the information provides detailed data about the unique breath signatures characteristic of the various diseases. Our system has detected and classified various diseases with an average accuracy of 86%.

This is a new and promising direction for diagnosis and classification of diseases, which is characterized not only by considerable accuracy but also by low cost, low electricity consumption, miniaturization, comfort and the possibility of repeating the test easily.”

“Breath is an excellent raw material for diagnosis,” said Prof. Haick. “It is available without the need for invasive and unpleasant procedures, it’s not dangerous, and you can sample it again and again if necessary.”

Here’s a schematic of the study, which the researchers have made available,

Diagram: A schematic view of the study. Two breath samples were taken from each subject, one was sent for chemical mapping using mass spectrometry, and the other was analyzed in the new system, which produced a clinical diagnosis based on the chemical fingerprint of the breath sample. Courtesy: Tech;nion

There is also a video, which covers much of the same ground as the press release but also includes information about the possible use of the Na-Nose technology in the European Union’s SniffPhone project,

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

Diagnosis and Classification of 17 Diseases from 1404 Subjects via Pattern Analysis of Exhaled Molecules by Morad K. Nakhleh, Haitham Amal, Raneen Jeries, Yoav Y. Broza, Manal Aboud, Alaa Gharra, Hodaya Ivgi, Salam Khatib, Shifaa Badarneh, Lior Har-Shai, Lea Glass-Marmor, Izabella Lejbkowicz, Ariel Miller, Samih Badarny, Raz Winer, John Finberg, Sylvia Cohen-Kaminsky, Frédéric Perros, David Montani, Barbara Girerd, Gilles Garcia, Gérald Simonneau, Farid Nakhoul, Shira Baram, Raed Salim, Marwan Hakim, Maayan Gruber, Ohad Ronen, Tal Marshak, Ilana Doweck, Ofer Nativ, Zaher Bahouth, Da-you Shi, Wei Zhang, Qing-ling Hua, Yue-yin Pan, Li Tao, Hu Liu, Amir Karban, Eduard Koifman, Tova Rainis, Roberts Skapars, Armands Sivins, Guntis Ancans, Inta Liepniece-Karele, Ilze Kikuste, Ieva Lasina, Ivars Tolmanis, Douglas Johnson, Stuart Z. Millstone, Jennifer Fulton, John W. Wells, Larry H. Wilf, Marc Humbert, Marcis Leja, Nir Peled, and Hossam Haick. ACS Nano, Article ASAP DOI: 10.1021/acsnano.6b04930 Publication Date (Web): December 21, 2016

Copyright © 2017 American Chemical Society

This paper appears to be open access.

As for SniffPhone, they’re hoping that Na-Nose or something like it will allow them to modify smartphones in a way that will allow diseases to be detected.

I can’t help wondering who will own the data if your smartphone detects a disease. If you think that’s an idle question, here’s an excerpt from Sue Halpern’s Dec. 22, 2016 review of two books (“Weapons of Math Destruction: How Big Data Increases Inequality and Threatens Democracy” by Cathy O’Neil and “Virtual Competition: The Promise and Perils of the Algorithm-Driven Economy” by Ariel Ezrachi and Maurice E. Stucke) for the New York Times Review of Books,

We give our data away. We give it away in drips and drops, not thinking that data brokers will collect it and sell it, let alone that it will be used against us. There are now private, unregulated DNA databases culled, in part, from DNA samples people supply to genealogical websites in pursuit of their ancestry. These samples are available online to be compared with crime scene DNA without a warrant or court order. (Police are also amassing their own DNA databases by swabbing cheeks during routine stops.) In the estimation of the Electronic Frontier Foundation, this will make it more likely that people will be implicated in crimes they did not commit.

Or consider the data from fitness trackers, like Fitbit. As reported in The Intercept:

During a 2013 FTC panel on “Connected Health and Fitness,” University of Colorado law professor Scott Peppet said, “I can paint an incredibly detailed and rich picture of who you are based on your Fitbit data,” adding, “That data is so high quality that I can do things like price insurance premiums or I could probably evaluate your credit score incredibly accurately.”

Halpern’s piece is well worth reading in its entirety.

Achieving ultra-low friction without oil

Oiled gears as small parts of large mechanism Courtesy: Georgia Institute of Technology

Oiled gears as small parts of large mechanism Courtesy: Georgia Institute of Technology

Those gears are gorgeous, especially in full size; I will be giving a link to a full size version in a bit. Meanwhile, an Oct. 11, 2016 news item on Nanowerk makes an announcement about ultra-low friction without oil,

Researchers at Georgia Institute of Technology [Georgia Tech; US] have developed a new process for treating metal surfaces that has the potential to improve efficiency in piston engines and a range of other equipment.

The method improves the ability of metal surfaces to bond with oil, significantly reducing friction without special oil additives.

“About 50 percent of the mechanical energy losses in an internal combustion engine result from piston assembly friction. So if we can reduce the friction, we can save energy and reduce fuel and oil consumption,” said Michael Varenberg, an assistant professor in Georgia Tech’s George W. Woodruff School of Mechanical Engineering.

An Oct. 5, 2016 Georgia Tech news release (also on EurekAlert but dated Oct. 11, 2016), which originated the news item, describes the research in more detail,

In the study, which was published Oct. 5 [2016] in the journal Tribology Letters, the researchers at Georgia Tech and Technion – Israel Institute of Technology tested treating the surface of cast iron blocks by blasting it with mixture of copper sulfide and aluminum oxide. The shot peening modified the surface chemically that changed how oil molecules bonded with the metal and led to a superior surface lubricity.

“We want oil molecules to be connected strongly to the surface. Traditionally this connection is created by putting additives in the oil,” Varenberg said. “In this specific case, we shot peen the surface with a blend of alumina and copper sulfide particles.  Making the surface more active chemically by deforming it allows for replacement reaction to form iron sulfide on top of the iron. And iron sulfides are known for very strong bonds with oil molecules.”

Oil is the primary tool used to reduce the friction that occurs when two surfaces slide in contact. The new surface treatment results in an ultra-low friction coefficient of about 0.01 in a base oil environment, which is about 10 times less than a friction coefficient obtained on a reference untreated surface, the researchers reported.

“The reported result surpasses the performance of the best current commercial oils and is similar to the performance of lubricants formulated with tungsten disulfide-based nanoparticles, but critically, our process does not use any expensive nanostructured media,” Varenberg said.

The method for reducing surface friction is flexible and similar results can be achieved using a variety of processes other than shot peening, such as lapping, honing, burnishing, laser shock peening, the researchers suggest. That would make the process even easier to adapt to a range of uses and industries. The researchers plan to continue to examine that fundamental functional principles and physicochemical mechanisms that caused the treatment to be so successful.

“This straightforward, scalable pathway to ultra-low friction opens new horizons for surface engineering, and it could significantly reduce energy losses on an industrial scale,” Varenberg said. “Moreover, our finding may result in a paradigm shift in the art of lubrication and initiate a whole new direction in surface science and engineering due to the generality of the idea and a broad range of potential applications.”

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

Mechano-Chemical Surface Modification with Cu2S: Inducing Superior Lubricity by Michael Varenberg, Grigory Ryk, Alexander Yakhnis, Yuri Kligerman, Neha Kondekar, & Matthew T. McDowell. Tribol Lett (2016) 64: 28. doi:10.1007/s11249-016-0758-8 First online: Oct. 5, 2016

This paper is behind a paywall.

Nanotechnology delivery system for skin disease therapies

A Feb. 29, 2016 news item on ScienceDaily announces a new development concerning free radicals that may be helpful with skin diseases and pathologies,

Researchers at The Hebrew University of Jerusalem have developed a nanotechnology-based delivery system containing a protective cellular pathway inducer that activates the body’s natural defense against free radicals efficiently, a development that could control a variety of skin pathologies and disorders.

A Feb. 29, 2016 Hebrew University of Jerusalem press release on EurekAlert, which originated the news item, expands on the theme,

The human skin is constantly exposed to various pollutants, UV rays, radiation and other stressors that exist in our day-to-day environment. When they filter into the body they can create Reactive Oxygen Species (ROS) – oxygen molecules known as Free Radicals, which are able to damage and destroy cells, including lipids, proteins and DNA.

In the skin – the largest organ of the body – an excess of ROS can lead to various skin conditions, including inflammatory diseases, pigmenting disorders, wrinkles and some types of skin cancer, and can also affect internal organs. This damage is known as Oxidative Stress.

The body is naturally equipped with defense mechanisms to counter oxidative stress. It has anti-oxidants and, more importantly, anti-oxidant enzymes that attack the ROS before they cause damage.

In a review article published in the journal Cosmetics, a PhD student from The Hebrew University of Jerusalem, working in collaboration with researchers at the Technion – Israel Institute of Technology, suggested an innovative way to invigorate the body to produce antioxidant enzymes, while maintaining skin cell redox balance – a gentle equilibrium between Reactive Oxygen Species and their detoxification.

“The approach of using the body’s own defense system is very effective. We showed that activation of the body’s defense system with the aid of a unique delivery system is feasible, and may leverage dermal cure,” said Hebrew University researcher Maya Ben-Yehuda Greenwald.

Ben-Yehuda Greenwald showed that applying nano-size droplets of microemulsion liquids containing a cellular protective pathway inducer into the skin activates the natural skin defense systems.

“Currently, there are many scientific studies supporting the activation of the body’s defense mechanisms. However, none of these studies has demonstrated the use of a nanotechnology-based delivery system to do so,” Ben-Yehuda Greenwald said.

Production of antioxidant enzymes in the body is signaled in the DNA by activation of Nrf2 – a powerful protein that exists in every cell in our body. This Nrf2 cellular-protective signaling pathway is a major intersection of many other signaling pathways affecting each other and determining cell functionality and fate. Nrf2 is capable of coordinating the cellular response to internal as well as external stressors by tight regulation of phase-II protective enzymes, such as the antioxidant enzymes.

Ben-Yehuda Greenwald has also discovered a new family of compounds capable of activating the Nrf2 pathway. Moreover, by incorporating them into the unique delivery system she has developed, she managed to efficiently stimulate the activation of the Nrf2 pathway and mimic the activity of the body’s’ natural way of coping with a variety of stress conditions.

“The formula we have created could be used in topical medication for treating skin conditions. Our formula could be used both as preventive means and for treatment of various skin conditions, such as infections, over-exposure to UV irradiation, inflammatory conditions, and also internal disease,” she said.

While the researchers focused on the skin, the formulation could prove to be effective in enhancing the body’s natural protection against the damaging effects of ROS in other parts of the body, such as inflammation in cardiovascular diseases, heart attack, cancer, multiple sclerosis and Alzheimer’s.

Here’s an image provided by Ben-Yehuda Greenwald illustrating the team’s work,

Caption: These are the consequences of skin exposure to stressors. Credit: Maya Ben-Yehuda Greenwald

Caption: These are the consequences of skin exposure to stressors. Credit: Maya Ben-Yehuda Greenwald

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

Skin Redox Balance Maintenance: The Need for an Nrf2-Activator Delivery System by Maya Ben-Yehuda Greenwald, Shmuel Ben-Sasson, Havazelet Bianco-Peled, and Ron Kohen. Cosmetics 2016, 3(1), 1; doi:10.3390/cosmetics3010001 Published: 15 January 2016

This paper appears to be open access.

Silicon dioxide nanoparticles may affect the heart

This is an interesting piece of research although it’s difficult to draw conclusions since the testing was ‘in vitro’, which literally means ‘in glass’ and in practice means testing cells in a test tube, a petri dish or, possibly, on a slide. That said, this work centering on silicon dioxide nanoparticles, which are increasingly used in biomedical applications, suggests further investigation is warranted. From a Jan. 9, 2015 news item on Azonano,

Nanoparticles, extremely tiny particles measured in billionths of a meter, are increasingly everywhere, and especially in biomedical products. Their toxicity has been researched in general terms, but now a team of Israeli scientists has for the first time found that exposure nanoparticles (NPs) of silicon dioxide (SiO2) can play a major role in the development of cardiovascular diseases when the NP cross tissue and cellular barriers and also find their way into the circulatory system.

A Jan. 8, 2015American Technion Society news release by Kevin Hattori, which originated the news item, describes the research in more detail,

“Environmental exposure to nanoparticles is becoming unavoidable due to the rapid expansion of nanotechnology,” says the study’s lead author, Prof. Michael Aviram, of the Technion Faculty of Medicine, “This exposure may be especially chronic for those employed in research laboratories and in high tech industry where workers handle, manufacture, use and dispose of nanoparticles. Products that use silica-based nanoparticles for biomedical uses, such as various chips, drug or gene delivery and tracking, imaging, ultrasound therapy, and diagnostics, may also pose an increased cardiovascular risk for consumers as well.” [emphasis mine]

In this study, researchers exposed cultured laboratory mouse cells resembling the arterial wall cells to NPs of silicon dioxide and investigated the effects. SiO2 NPs are toxic to and have significant adverse effects on macrophages. a type of white blood cell that take up lipids, leading to atherosclerotic lesion development and its consequent cardiovascular events, such as heart attack or stroke. Macrophages accumulation in the arterial wall under atherogenic conditions such as high cholesterol, triglycerides, oxidative stress – are converted into lipids, or laden “foam cells” which, in turn, accelerate atherosclerosis development.

“Macrophage foam cells accumulation in the arterial wall are a key cell type in the development of atherosclerosis, which is an inflammatory disease” says co-author Dr. Lauren Petrick. “The aims of our study were to gain additional insight into the cardiovascular risk associated with silicon dioxide nanoparticle exposure and discover the mechanisms behind Si02’s induced atherogenic effects on macrophages. We also wanted to use nanoparticles as a model for ultrafine particle (UFP) exposure as cardiovascular disease risk factors.”

Both NPs and UFPs can be inhaled and induce negative biological effects. [emphasis mine] However, until this study, their effect on the development of atherosclerosis has been largely unknown. Here, researchers have discovered for the first time that the toxicity of silicon dioxide nanoparticles has a “significant and substantial effect on the accumulation of triglycerides in the macrophages,” at all exposure concentrations analyzed, and that they also “increase oxidative stress and toxicity.”

A recent update from the American Heart Association also suggested that “fine particles” in air pollution leads to elevated risk for cardiovascular diseases. However, more research was needed to examine the role of “ultrafine particles” (which are much smaller than “fine particles”) on atherosclerosis development and cardiovascular risk.

“The number of nano-based consumer products has risen a thousand fold in recent years, with an estimated world market of $3 trillion by the year 2020,” conclude the researchers. “This reality leads to increased human exposure and interaction of silica-based nanoparticles with biological systems. Because our research demonstrates a clear cardiovascular health risk associated with this trend, steps need to be taken to help ensure that potential health and environmental hazards are being addressed at the same time as the nanotechnology is being developed.

Unfortunately, there seems to be a little exaggeration at work in this news release. For example, I’m not sure how a consumer would go about inhaling a computer chip or more specifically the silicon dioxide nanoparticles embedded in the chip although I can see how someone involved in the manufacture of the chip might be exposed and inhale silicon dioxide nanoparticles. I’m not trying to negate the research but do want to point out that it has limitations.

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

Silicon dioxide nanoparticles increase macrophage atherogenicity: Stimulation of cellular cytotoxicity, oxidative stress, and triglycerides accumulation by Lauren Petrick, Mira Rosenblat, Nicole Paland, and Michael Aviram. Article first published online: 28 NOV 2014 DOI: 10.1002/tox.22084

Copyright © 2014 Wiley Periodicals, Inc.

This article is behind a paywall.

Replacing copper wire in motors?

Finnish researchers at Lappeenranta University of Technology (LUT) believe it may be possible to replace copper wire used in motors with spun carbon nanotubes. From an Oct. 15, 2014 news item on Azonano,

Lappeenranta University of Technology (LUT) introduces the first electrical motor applying carbon nanotube yarn. The material replaces copper wires in windings. The motor is a step towards lightweight, efficient electric drives. Its output power is 40 W and rotation speed 15000 rpm.

Aiming at upgrading the performance and energy efficiency of electrical machines, higher-conductivity wires are searched for windings. Here, the new technology may revolutionize the industry. The best carbon nanotubes (CNTs) demonstrate conductivities far beyond the best metals; CNT windings may have double the conductivity of copper windings.

”If we keep the design parameters unchanged only replacing copper with carbon nanotube yarns, the Joule losses in windings can be reduced to half of present machine losses. By lighter and more ecological CNT yarn, we can reduce machine dimensions and CO2 emissions in manufacturing and operation. Machines could also be run in higher temperatures,” says Professor Pyrhönen [Juha Pyrhönen], leading the prototype design at LUT.

An Oct. ??, 2014 (?) LUT press release, which originated the news item, further describes the work,

Traditionally, the windings in electrical machines are made of copper, which has the second best conductivity of metals at room temperature. Despite the high conductivity of copper, a large proportion of the electrical machine losses occur in the copper windings. For this reason, the Joule losses are often referred to as copper losses. The carbon nanotube yarn does not have a definite upper limit for conductivity (e.g. values of 100 MS/m have already been measured).

According to Pyrhönen, the electrical machines are so ubiquitous in everyday life that we often forget about their presence. In a single-family house alone there can be tens of electrical machines in various household appliances such as refrigerators, washing machines, hair dryers, and ventilators.

“In the industry, the number of electrical motors is enormous: there can be up to tens of thousands of motors in a single process industry unit. All these use copper in the windings. Consequently, finding a more efficient material to replace the copper conductors would lead to major changes in the industry,” tells Professor Pyrhönen.

There are big plans for this work according to the press release,

The prototype motor uses carbon nanotube yarns spun and converted into an isolated tape by a Japanese-Dutch company Teijin Aramid, which has developed the spinning technology in collaboration with Rice University, the USA. The industrial applications of the new material are still in their infancy; scaling up the production capacity together with improving the yarn performance will facilitate major steps in the future, believes Business Development Manager Dr. Marcin Otto from Teijin Aramid, agreeing with Professor Pyrhönen.

“There is a significant improvement potential in the electrical machines, but we are now facing the limits of material physics set by traditional winding materials. Superconductivity appears not to develop to such a level that it could, in general, be applied to electrical machines. Carbonic materials, however, seem to have a pole position: We expect that in the future, the conductivity of carbon nanotube yarns could be even three times the practical conductivity of copper in electrical machines. In addition, carbon is abundant while copper needs to be mined or recycled by heavy industrial processes.”

The researchers have produced this video about their research,

There’s a reference to some work done at Rice University (Texas, US) with Teijin Armid (Japanese-Dutch company) and Technion Institute (Israel) with spinning carbon nanotubes into threads that look like black cotton (you’ll see the threads in the video). It’s this work that has made the latest research in Finland possible. I have more about the the Rice/Teijin Armid/Technion CNT project in my Jan. 11, 2013 posting, Prima donna of nanomaterials (carbon nanotubes) tamed by scientists at Rice University (Texas, US), Teijin Armid (Dutch/Japanese company), and Technion Institute (based in Israel).

Technion-Israel Institute of Technology and the University of Waterloo (Canada) together at last

A March 18, 2014 University of Waterloo news release describes a new agreement signed at a joint Technion-Israel Institute of Technology-University of Waterloo conference held in Israel.

“As two of the world’s top innovation universities, the University of Waterloo and Technion are natural partners,” said Feridun Hamdullahpur, president and vice-chancellor of the University of Waterloo. “This partnership positions both Waterloo and Technion for accelerated progress in the key areas of quantum information science, nanotechnology, and water. [emphasis mine] These disciplines will help to shape the future of communities, industries, and everyday life.”

The conference to mark the start of the new partnership, and a reciprocal event in Waterloo planned for later in 2014, is funded by a donation to the University of Waterloo from The Gerald Schwartz & Heather Reisman Foundation.

“The agreement between the University of Waterloo and Technion will lead to joint research projects between Israeli and Canadian scientists in areas crucial for making our world a better place,” said Peretz Lavie, president of Technion. “I could not think of a better partner for such projects than the University of Waterloo.”

The new partnership agreement will connect students and faculty from both institutions with global markets through technology transfer and commercialization opportunities with industrial partners in Canada and in Israel.

“This partnership between two global innovation leaders puts in place the conditions to support research breakthroughs and new opportunities for commercialization on an international scale,” said George Dixon, vice-president of research at Waterloo. “University of Waterloo and Technion have a history of research collaboration going back almost 20 years.”

Which one of these items does not fit on the list “quantum information science, nanotechnology, and water?” I pick water. I think they mean water remediation or water desalination or, perhaps, water research.

Given the issues with the lack of potable water in that region the interest in water is eminently understandable. (My Feb. 24, 2014 posting mentions the situation in the Middle East in the context of water desalination research at a new nanotechnology at Oman’s Sultan Qaboos University.)

Electronic skin and its evolution

Michael Berger has featured an article in the journal Advanced Materials, which reviews 25 years of work on e-skin (aka, electronic skin or artificial skin) in his Nov. 15, 2013 Nanowerk Spotlight series article ,

Advances in materials, fabrication strategies and device designs for flexible and stretchable electronics and sensors make it possible to envision a not-too-distant future where ultra-thin, flexible circuits based on inorganic semiconductors can be wrapped and attached to any imaginable surface, including body parts and even internal organs. Robotic technologies will also benefit as it becomes possible to fabricate electronic skin (‘e-skin’) that, for instance, could allow surgical robots to interact, in a soft contacting mode, with their surroundings through touch. In addition to giving robots a finer sense of touch, engineers believe that e-skin technology could also be used to create things like wallpapers that double as touchscreen displays and dashboard laminates that allow drivers to adjust electronic controls with the wave of a hand.

Here’s a link to and a citation for the 25-year review of work on e-skin,

25th Anniversary Article: The Evolution of Electronic Skin (E-Skin): A Brief History, Design Considerations, and Recent Progress by Mallory L. Hammock, Alex Chortos, Benjamin C.-K. Tee, Jeffrey B.-H. Tok, and Zhenan Bao. Advanced Materials Volume 25, Issue 42, pages 5997–6038, November 13, 2013 Article first published online: 22 OCT 2013 DOI: 10.1002/adma.201302240

© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

The review article is behind a paywall but Berger’s synopsis offers a good overview* and tidbits such as this timeline (Berger offers a larger version) which includes important moments in science fiction (Note: Links in the caption have been removed),

Figure 1. A brief chronology of the evolution of e-skin. We emphasize several science fictional events in popular culture that inspired subsequent critical technological advancements in the development of e-skin. Images reproduced with permission: “micro-structured pressure sensor,”[18] “stretchable OLEDs,”[20b] “stretchable OPVs,”[21a] “stretchable, transparent e-skin,”[22] “macroscale nanowire e-skin,”[23a] “rechargeable, stretchable batteries,”[137] “interlocked e-skin.”[25] Copyright, respectively, 2010, 2009, 2012, 2005, 2010, 2013, 2012. Macmillan Publishers Ltd. “Flexible, active-matrix e-skin” image reproduced with permission.[26a] Copyright, 2004. National Academy of Sciences USA. “Epidermal electronics” image reproduced with permission.[390a] Copyright, American Association for the Advancement of Science. “Stretchable batteries” image reproduced with permission.[27] “Infrared e-skin” image reproduced with permission.[8b] Copyright 2001, IEEE. “Anthropomorphic cybernetic hand” image reproduced with permission.[426] Copyright 2006, IEEE. [downloaded from http://onlinelibrary.wiley.com.proxy.lib.sfu.ca/doi/10.1002/adma.201302240/full]

Figure 1. A brief chronology of the evolution of e-skin. We emphasize several science fictional events in popular culture that inspired subsequent critical technological advancements in the development of e-skin. Images reproduced with permission: “micro-structured pressure sensor,”[18] “stretchable OLEDs,”[20b] “stretchable OPVs,”[21a] “stretchable, transparent e-skin,”[22] “macroscale nanowire e-skin,”[23a] “rechargeable, stretchable batteries,”[137] “interlocked e-skin.”[25] Copyright, respectively, 2010, 2009, 2012, 2005, 2010, 2013, 2012. Macmillan Publishers Ltd. “Flexible, active-matrix e-skin” image reproduced with permission.[26a] Copyright, 2004. National Academy of Sciences USA. “Epidermal electronics” image reproduced with permission.[390a] Copyright, American Association for the Advancement of Science. “Stretchable batteries” image reproduced with permission.[27] “Infrared e-skin” image reproduced with permission.[8b] Copyright 2001, IEEE. “Anthropomorphic cybernetic hand” image reproduced with permission.[426] Copyright 2006, IEEE. [downloaded from http://onlinelibrary.wiley.com.proxy.lib.sfu.ca/doi/10.1002/adma.201302240/full]

Here’s an excerpt from the review article outlining the 1970s – 1990s period featuring some of the science fiction which has influenced the science (Note: Links have been removed),

The prospect of creating artificial skin was in many ways inspired by science fiction, which propelled the possibility of e-skin into the imagination of both the general public as well as the scientific community. One of the first science fiction books to explore the use of mechanical replacement organs was Caidin’s Cyborg in 1971, on which the famed Six Million Dollar Man television series about a man with a bionic replacement arm and eye was later based (1974).[4] Shortly after, at the beginning of the 1980s, George Lucas created a vision of a future with e-skin in the famous Star Wars series. In particular, he depicted a scene showing a medical robot installing an electronic hand with full sensory perception on the main character, Luke Skywalker.[5] Shortly after, in 1984, the Terminator movie series depicted humanoid robots and even a self-healing robot.[6] These fictitious renditions of e-skin took place against a real-life backdrop of vibrant microelectronics research that began bridging science fiction with scientific reality.

Early technological advancements in the development of e-skin were concomitant with their science fiction inspirations. In 1974, Clippinger et al. demonstrated a prosthetic hand capable of discrete sensor feedback.[7] Nearly a decade later, Hewlett-Packard (HP) marketed a personal computer (HP-150) that was equipped with a touchscreen, allowing users to activate functions by simply touching the display. It was the first mass-marketed electronic device capitalizing on the intuitive nature of human touch. In 1985, General Electric (GE) built the first sensitive skin for a robotic arm using discrete infrared sensors placed on a flexible sheet at a resolution of ≈5 cm.[8] The fabricated sensitive skin was proximally aware of its surroundings, allowing the robot’s arm to avert potential obstacles and effectively maneuver within its physical environment. Despite the robotic arm’s lack of fingers and low resolution, it was capable of demonstrating that electronics integrated into a membrane could allow for natural human–machine interaction. For example, the robotic arm was able to ‘dance’ with a ballerina without any pre-programmed motions.[8] In addition to the ability of an artificial skin to interact with its surroundings, it is equally critical that the artificial skin mimics the mechanical properties of human skin to accommodate its various motions. Hence, to build life-like prosthetics or humanoid robots, soft, flexible, and stretchable electronics needed to be developed.

In the 1990s, scientists began using flexible electronic materials to create large-area, low-cost and printable sensor sheets. Jiang et al. proposed one of the first flexible sensor sheets for tactile shear force sensing by creating silicon (Si) micro-electro-mechanical (MEM) islands by etching thin Si wafers and integrating them on flexible polyimide foils.[9] Much work has since been done to enhance the reliability of large sensor sheets to mechanical bending.[10] Around the same time, flexible arrays fabricated from organic semiconductors began to emerge that rivaled the performance of amorphous Si.[11]

Just before the turn of the millennium, the first “Sensitive Skin Workshop” was held in Washington DC under the aegis of the National Science Foundation and the Defense Advanced Research Projects Agency, bringing together approximately sixty researchers from different sectors of academia, industry, and government. It was discovered that there was significant industrial interest in e-skins for various applications, ranging from robotics to health care. A summary of concepts outlined in the workshop was compiled by Lumelsky et al.[12] In the early 2000s, the pace of e-skin development significantly increased as a result of this workshop, and researchers began to explore different types of sensors that could be more easily integrated with microprocessors.

I have written about e-skin a number of times, most recently in a July 9, 2013 posting about work on flexible sensors and gold nanoparticles being conducted at Technion-Israel Institute of Technology. This review helps to contextualize projects such as the one at Technion and elsewhere.

*To avoid redundancy ‘synopsis’ was replaced by ‘overview’ on Oct. 19, 2015.

The gold beneath your skin (artificial skin, that is)

Artificial skin that can sense as if it were real skin isn’t here yet but scientists at Technion-Israel Institute of Technology have created a flexible sensor that could fulfill that promise. From a July 9, 2013 news item on Azonano,

Using tiny gold particles and a kind of resin, a team of scientists at the Technion-Israel Institute of Technology has discovered how to make a new kind of flexible sensor that one day could be integrated into electronic skin, or e-skin.

If scientists learn how to attach e-skin to prosthetic limbs, people with amputations might once again be able to feel changes in their environments. The findings appear in the June issue of ACS Applied Materials & Interfaces.

The July 8, 2013 American Technion Society news release by Kevin Hattori, which originated the news item, describes the problems with developing flexible sensors that can mimic natural skin,

Researchers have long been interested in flexible sensors, but have had trouble adapting them for real-world use. To make its way into mainstream society, a flexible sensor would have to run on low voltage (so it would be compatible with the batteries in today’s portable devices), measure a wide range of pressures, and make more than one measurement at a time, including humidity, temperature, pressure, and the presence of chemicals. In addition, these sensors would also have to be able to be made quickly, easily, and cheaply.

Here are more details about the sensor and about how the researchers created it,

The Technion team’s sensor has all of these qualities. The secret is the use of monolayer-capped nanoparticles that are only 5-8 nanometers in diameter. They are made of gold and surrounded by connector molecules called ligands. In fact, “monolayer-capped nanoparticles can be thought of as flowers, where the center of the flower is the gold or metal nanoparticle and the petals are the monolayer of organic ligands that generally protect it,” says Haick.

The team discovered that when these nanoparticles are laid on top of a substrate – in this case, made of PET (flexible polyethylene terephthalate), the same plastic found in soda bottles – the resulting compound conducted electricity differently depending on how the substrate was bent. (The bending motion brings some particles closer to others, increasing how quickly electrons can pass between them.) This electrical property means that the sensor can detect a large range of pressures, from tens of milligrams to tens of grams. “The sensor is very stable and can be attached to any surface shape while keeping the function stable,” says Dr. Nir Peled, Head of the Thoracic Cancer Research and Detection Center at Israel’s Sheba Medical Center, who was not involved in the research.

And by varying how thick the substrate is, as well as what it is made of, scientists can modify how sensitive the sensor is. Because these sensors can be customized, they could in the future perform a variety of other tasks, including monitoring strain on bridges and detecting cracks in engines.

According to research team leader Professor Hossam Haick the new sensor is more sensitive (x 10 or more) in touch than existing touch-based e-skin.

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

Tunable Touch Sensor and Combined Sensing Platform: Toward Nanoparticle-based Electronic Skin by Meital Segev-Bar , Avigail Landman, Maayan Nir-Shapira, Gregory Shuster, and Hossam Haick. ACS Appl. Mater. Interfaces, 2013, 5 (12), pp 5531–5541 DOI: 10.1021/am400757q Publication Date (Web): June 4, 2013

Copyright © 2013 American Chemical Society

The paper is behind a paywall.