Tag Archives: Cornell University

Graphene-based sensor mimics pain (mu-opioid) receptor

I once had a job where I had to perform literature searches and read papers on pain research as it related to morphine tolerance. Not a pleasant task, it has left me eager to encourage and write about alternatives to animal testing, a key component of pain research. So, with a ‘song in my heart’, I feature this research from the University of Pennsylvania written up in a May 12, 2014 news item on ScienceDaily,

Almost every biological process involves sensing the presence of a certain chemical. Finely tuned over millions of years of evolution, the body’s different receptors are shaped to accept certain target chemicals. When they bind, the receptors tell their host cells to produce nerve impulses, regulate metabolism, defend the body against invaders or myriad other actions depending on the cell, receptor and chemical type.

Now, researchers from the University of Pennsylvania have led an effort to create an artificial chemical sensor based on one of the human body’s most important receptors, one that is critical in the action of painkillers and anesthetics. In these devices, the receptors’ activation produces an electrical response rather than a biochemical one, allowing that response to be read out by a computer.

By attaching a modified version of this mu-opioid receptor to strips of graphene, they have shown a way to mass produce devices that could be useful in drug development and a variety of diagnostic tests. And because the mu-opioid receptor belongs to the most common class of such chemical sensors, the findings suggest that the same technique could be applied to detect a wide range of biologically relevant chemicals.

A May 6, 2014 University of Pennsylvania news release, which originated the news item, describes the main teams involved in this research along with why and how they worked together (Note: Links have been removed),

The study, published in the journal Nano Letters, was led by A.T. Charlie Johnson, director of Penn’s Nano/Bio Interface Center and professor of physics in Penn’s School of Arts & Sciences; Renyu Liu, assistant professor of anesthesiology in Penn’s Perelman School of Medicine; and Mitchell Lerner, then a graduate student in Johnson’s lab. It was made possible through a collaboration with Jeffery Saven, professor of chemistry in Penn Arts & Sciences. The Penn team also worked with researchers from the Seoul National University in South Korea.

Their study combines recent advances from several disciplines.

Johnson’s group has extensive experience attaching biological components to nanomaterials for use in chemical detectors. Previous studies have involved wrapping carbon nanotubes with single-stranded DNA to detect odors related to cancer and attaching antibodies to nanotubes to detect the presence of the bacteria associated with Lyme disease.

After Saven and Liu addressed these problems with the redesigned receptor, they saw that it might be useful to Johnson, who had previously published a study on attaching a similar receptor protein to carbon nanotubes. In that case, the protein was difficult to grow genetically, and Johnson and his colleagues also needed to include additional biological structures from the receptors’ natural membranes in order to keep them stable.

In contrast, the computationally redesigned protein could be readily grown and attached directly to graphene, opening up the possibility of mass producing biosensor devices that utilize these receptors.

“Due to the challenges associated with isolating these receptors from their membrane environment without losing functionality,” Liu said, “the traditional methods of studying them involved indirectly investigating the interactions between opioid and the receptor via radioactive or fluorescent labeled ligands, for example. This multi-disciplinary effort overcame those difficulties, enabling us to investigate these interactions directly in a cell free system without the need to label any ligands.”

With Saven and Liu providing a version of the receptor that could stably bind to sheets of graphene, Johnson’s team refined their process of manufacturing those sheets and connecting them to the circuitry necessary to make functional devices.

The news release provides more technical details about the graphene sensor,

“We start by growing a piece of graphene that is about six inches wide by 12 inches long,” Johnson said. “That’s a pretty big piece of graphene, but we don’t work with the whole thing at once. Mitchell Lerner, the lead author of the study, came up with a very clever idea to cut down on chemical contamination. We start with a piece that is about an inch square, then separate them into ribbons that are about 50 microns across.

“The nice thing about these ribbons is that we can put them right on top of the rest of the circuitry, and then go on to attach the receptors. This really reduces the potential for contamination, which is important because contamination greatly degrades the electrical properties we measure.”

Because the mechanism by which the device reports on the presence of the target molecule relies only on the receptor’s proximity to the nanostructure when it binds to the target, Johnson’s team could employ the same chemical technique for attaching the antibodies and other receptors used in earlier studies.

Once attached to the ribbons, the opioid receptors would produce changes in the surrounding graphene’s electrical properties whenever they bound to their target. Those changes would then produce electrical signals that would be transmitted to a computer via neighboring electrodes.

The high reliability of the manufacturing process — only one of the 193 devices on the chip failed — enables applications in both clinical diagnostics and further research. [emphasis mine]

“We can measure each device individually and average the results, which greatly reduces the noise,” said Johnson. “Or you could imagine attaching 10 different kinds of receptors to 20 devices each, all on the same chip, if you wanted to test for multiple chemicals at once.”

In the researchers’ experiment, they tested their devices’ ability to detect the concentration of a single type of molecule. They used naltrexone, a drug used in alcohol and opioid addiction treatment, because it binds to and blocks the natural opioid receptors that produce the narcotic effects patients seek.

“It’s not clear whether the receptors on the devices are as selective as they are in the biological context,” Saven said, “as the ones on your cells can tell the difference between an agonist, like morphine, and an antagonist, like naltrexone, which binds to the receptor but does nothing. By working with the receptor-functionalized graphene devices, however, not only can we make better diagnostic tools, but we can also potentially get a better understanding of how the bimolecular system actually works in the body.”

“Many novel opioids have been developed over the centuries,” Liu said. “However, none of them has achieved potent analgesic effects without notorious side effects, including devastating addiction and respiratory depression. This novel tool could potentially aid the development of new opioids that minimize these side effects.”

Wherever these devices find applications, they are a testament to the potential usefulness of the Nobel-prize winning material they are based on.

“Graphene gives us an advantage,” Johnson said, “in that its uniformity allows us to make 192 devices on a one-inch chip, all at the same time. There are still a number of things we need to work out, but this is definitely a pathway to making these devices in large quantities.”

There is no mention of animal research but it seems likely to me that this work could lead to a decreased use of animals in pain research.

This project must have been quite something as it involved collaboration across many institutions (from the news release),

Also contributing to the study were Gang Hee Han, Sung Ju Hong and Alexander Crook of Penn Arts & Sciences’ Department of Physics and Astronomy; Felipe Matsunaga and Jin Xi of the Department of Anesthesiology at the Perelman School of Medicine, José Manuel Pérez-Aguilar of Penn Arts & Sciences’ Department of Chemistry; and Yung Woo Park of Seoul National University. Mitchell Lerner is now at SPAWAR Systems Center Pacific, Felipe Matsunaga at Albert Einstein College of Medicine, José Manuel Pérez-Aguilar at Cornell University and Sung Ju Hong at Seoul National University.

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

Scalable Production of Highly Sensitive Nanosensors Based on Graphene Functionalized with a Designed G Protein-Coupled Receptor by Mitchell B. Lerner, Felipe Matsunaga, Gang Hee Han, Sung Ju Hong, Jin Xi, Alexander Crook, Jose Manuel Perez-Aguilar, Yung Woo Park, Jeffery G. Saven, Renyu Liu, and A. T. Charlie Johnson.Nano Lett., Article ASAP
DOI: 10.1021/nl5006349 Publication Date (Web): April 17, 2014
Copyright © 2014 American Chemical Society

This paper is behind a paywall.

Art and nanotechnology at Cornell University’s (US) 2014 Biennial/Biennale

The 2014 Cornell [University located in New York State, US] Council for the Arts (CCA) Biennial, “Intimate Cosmologies: The Aesthetics of Scale in an Age of Nanotechnology” was announced in a Dec. 5, 2013 news item on Nanowerk,

A campuswide exhibition next fall will explore the cultural and human consequences of seeing the world at the micro and macro levels, through nanoscience and networked communications.

From Sept. 15 to Dec. 22, the 2014 Cornell Council for the Arts (CCA) Biennial, “Intimate Cosmologies: The Aesthetics of Scale in an Age of Nanotechnology”, will feature several events and principal projects by faculty and student investigators and guest artists – artist-in-residence kimsooja, Trevor Paglen and Rafael Lozano-Hemmer – working in collaboration with Cornell scientists and researchers.

The Dec.5, 2013 Cornell University news release written by Daniel Aloi, which originated the news item, describes the plans for and events leading to the biennale in Fall 2014,

The inaugural biennial theme was chosen to frame dynamic changes in 21st-century culture and art practice, and in nanoscale technology. The multidisciplinary initiative intends to engage students, faculty and the community in demonstrations of how radical shifts in scale have become commonplace, and how artists address realms of human experience lying beyond immediate sensory perception.

“Participating in the biennial is very exciting. We’re engaging the idea of nano and investigating scale as part of the value of art in performance,” said Beth Milles ’88, associate professor in the Department of Performing and Media Arts, who is collaborating on a project with students and with artist Lynn Tomlinson ’88.

A series of events and curricula this fall and spring are preceding the main Biennial exhibition. Joe Davis and Nathaniel Stern ’99 presented talks this semester, and CCA will bring Paul Thomas, Stephanie Rothenberg, Ana Viseu and others to campus in the coming months.

kimsooja, an acclaimed multimedia artist in performance, video and installation, addresses issues of the displaced self and recently represented Korea in the 55th Venice Biennale. She visited the campus Nov. 22-23 to meet with Uli Weisner and students from his research group, who will work with her to realize her large-scale installation here next fall.

Lozano-Hemmer has worked on both ends of the scale spectrum, from laser-etched poetry on human hairs to an interactive light sculpture over Mexico City, Toronto and Yamaguchi, Japan. Paglen’s researched-based work blurs lines between science, contemporary art, journalism and other disciplines.

The Biennial focus brings together artists and scientists who share a common curiosity regarding the position of the individual within the larger world, CCA Director Stephanie Owens said.

“Scientists are suddenly designers creating new forms,” she said. “And artists are increasingly interested in how things are structured, down to the biological level. Both are designing and discovering new ways of synthesizing natural properties of the material world with the fabricated experiences that extend and express the impact of these properties on our lives.”

Here’s a sample of the work that will be featured at the Biennale,

A prototype image of architecture professor Jenny Sabin's "eSkin" CCA Biennial project, an interactive simulation of a building façade that behaves like a living organism. Credit: Jenny Sabin Courtesy: Cornell University

A prototype image of architecture professor Jenny Sabin’s “eSkin” CCA Biennial project, an interactive simulation of a building façade that behaves like a living organism. Credit: Jenny Sabin Courtesy: Cornell University

Aloi includes a description of some of the exhibits and shows to be featured,

 The principal projects to be presented are:

  • “eSkin” – Architecture professor Jenny Sabin addresses ecology and sustainability issues with buildings that behave like organisms. Her project is an interactive simulation of a façade material incorporating nano- and microscale substrates plated with human cells.
  • “Nano Performance: In 13 Boxes” – Performing and media arts professor Beth Milles ‘88, animator/visual artist Lynn Tomlinson ‘88 and students from different majors will collaborate on 13 media installations and live performances situated across campus. Computer mapping and clues linking the project’s components will assist in “synthesizing the 13 events as a whole experience – it has a lot to do with discovering the performance,” Mills said.
  • “Nano Where: Gas In, Light Out” – Juan Hinestroza, fiber science, and So-Yeon Yoon, design and environmental analysis, will demonstrate the potential of molecular-level metal-organic frameworks as wearable sensors to detect methane and poisonous gases, using a sealed gas chamber and 3-D visual art.
  • “Paperscapes” – Three architecture students – teaching associate Caio Barboza ’13; Joseph Kennedy ’15 and Sonny Xu ’13 – will render the microscopic textures of a sheet of paper as a 3-D inhabitable landscape.
  • “When Art Exceeds Perception” – Ph.D. student in applied physics Robert Hovden will explore replication and plagiarism in nanoscale reproductions, 1,000 times smaller than the naked eye can see, of famous works of art inscribed onto a silicon crystal.

The Cornell Council for the Arts (CCA) has more information about their 2014 ‘nano Biennale’ here. This looks very exciting and I wish I could be there.

One final note, I’ve used the Biennale rather than Biennial as I associate Biennial and the US with the dates of 1776 and 1976 when the country celebrated its 200th anniversary.

Nano-enabled fique fiber filters harmful dyes from water

A Sept. 30, 2013 news item on ScienceDaily highlights a new technique for cleaning water,

A cheap and simple process using natural fibers embedded with nanoparticles can almost completely rid water of harmful textile dyes in minutes, report Cornell University and Colombian researchers who worked with native Colombian plant fibers.

Dyes, such as indigo blue used to color blue jeans, threaten waterways near textile plants in South America, India and China. Such dyes are toxic, and they discolor the water, thereby reducing light to the water plants, which limits photosynthesis and lowers the oxygen in the water.

The study, published in the August issue of the journal Green Chemistry, describes a proof of principle, but the researchers are testing how effectively their method treats such endocrine-disrupting water pollutants as phenols, pesticides, antibiotics, hormones and phthalates.

The Sept. 30, 2013 Cornell University news release on EurekAlert, which originated the news item,, describes the research in more detail,

The research takes advantage of nano-sized cavities found in cellulose that co-author Juan Hinestroza, Cornell associate professor of fiber science, has previously used to produce nanoparticles inside cotton fibers.

The paper describes the method: Colombian fique plant fibers, commonly used to make coffee bags, are immersed in a solution of sodium permanganate and then treated with ultrasound; as a result, manganese oxide molecules grow in the tiny cellulose cavities. Manganese oxides in the fibers react with the dyes and break them down into non-colored forms.

In the study, the treated fibers removed 99 percent of the dye from water within minutes. Furthermore, the same fibers can be used repeatedly — after eight cycles, the fibers still removed between 97 percent and 99 percent of the dye.

“No expensive or particular starting materials are needed to synthesize the biocomposite,” said Combariza [Marianny Combariza, co-author and researcher at Colombia's Universidad Industrial de Santander]. “The synthesis can be performed in a basic chemistry lab.”

“This is the first evidence of the effectiveness of this simple technique,” said Hinestroza. “It uses water-based chemistry, and it is easily transferable to real-world situations.”

The researchers are testing their process on other types of pollutants, other fibers and composite materials. “We are working now on developing a low-cost filtering unit prototype to treat polluted waters,” said Combariza. “We are not only focused on manganese oxides, we also work on a variety of materials based on transition metal oxides that show exceptional degradation activity.”

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

Biocomposite of nanostructured MnO2 and fique fibers for efficient dye degradation by Martha L. Chacón-Patiño,a   Cristian Blanco-Tirado, Juan P. Hinestroza, and  Marianny Y. Combariza. Green Chem., 2013,15, 2920-2928 DOI: 10.1039/C3GC40911B First published online 19 Aug 2013

This paper is behind a paywall.

For anyone not familiar with the fique plant,

The native Columbian fique plant, Frucraea Andina. (Credit: Vasyl Kacapyr)

The native Columbian fique plant, Frucraea Andina. (Credit: Vasyl Kacapyr)

I have mentioned Juan Hinestroza and the research he and his students perform on nano-enabled textiles a number of times including this May 15, 2012 posting on anti-malaria textiles.

Erasing time to create a temporal invisibility cloak

The idea of taking an eraser and just rubbing out embarrassing (or worse) incidents in one’s life is tempting but not yet possible despite efforts by researchers at Purdue University (Indiana, US). From a June 5, 2013 news item on ScienceDaily,

Researchers have demonstrated a method for “temporal cloaking” of optical communications, representing a potential tool to thwart would-be eavesdroppers and improve security for telecommunications.

“More work has to be done before this approach finds practical application, but it does use technology that could integrate smoothly into the existing telecommunications infrastructure,” said Purdue University graduate student Joseph Lukens, working with Andrew Weiner, the Scifres Family Distinguished Professor of Electrical and Computer Engineering.

Other researchers in 2012 invented temporal cloaking, but it cloaked only a tiny fraction — about a 10,000th of a percent — of the time available for sending data in optical communications. Now the Purdue researchers have increased that to about 46 percent, potentially making the concept practical for commercial applications.

The Purdue University June 5, 2013 news release, which originated the news item, describes the new technique,

The technique works by manipulating the phase, or timing, of light pulses. The propagation of light can be likened to waves in the ocean. If one wave is going up and interacts with another wave that’s going down, they cancel each other and the light has zero intensity. The phase determines the level of interference between these waves.

“By letting them interfere with each other you are able to make them add up to a one or a zero,” Lukens said. “The zero is a hole where there is nothing.”

Any data in regions where the signal is zero would be cloaked.

Controlling phase allows the transmission of signals in ones and zeros to send data over optical fibers. A critical piece of hardware is a component called a phase modulator, which is commonly found in optical communications to modify signals.

In temporal cloaking, two phase modulators are used to first create the holes and two more to  cover them up, making it look as though nothing was done to the signal.

“It’s a potentially higher level of security because it doesn’t even look like you are communicating,” Lukens said. “Eavesdroppers won’t realize the signal is cloaked because it looks like no signal is being sent.”

Such a technology also could find uses in the military, homeland security or law enforcement.

“It might be used to prevent communication between people, to corrupt their communication links without them knowing,” he said. “And you can turn it on and off, so if they suspected something strange was going on you could return it to normal communication.”

The technique could be improved to increase its operational bandwidth and the percentage of cloaking beyond 46 percent, he said.

In a July 14, 2011 posting I wrote about some of the research that laid the groundwork for this breakthrough at Purdue University,

Ian Sample in his July 13, 2011 posting on The Guardian Science blogs describes an entirely different approach, one that focusses on cloaking events rather than objects. From Samples’s posting,

The theoretical prospect of a “space-time” cloak – or “history editor” – was raised by Martin McCall and Paul Kinsler at Imperial College in a paper published earlier this year. The physicists explained that when light passes through a material, such as a lens, the light waves slow down. But it is possible to make a lens that splits the light in two, so that half – say the shorter wavelengths – speed up, while the other half, the longer wavelengths, slow down. This opens a gap in the light in which an event can be hidden, because half the light arrives before it has happened, and the other half arrives after the event.

In their paper, McCall and Kinsler outline a scenario whereby a video camera would be unable to record a crime being committed because there was a means of splitting the light such that 1/2 of it reached the camera before the crime occurred and the other 1/2  reached the camera afterwards. Fascinating, non?

It seems researchers at Cornell University have developed a device that can in a rudimentary fashion cloak events (from Samples’s posting),

The latest device, which has been shown to work for the first time by Moti Fridman and Alexander Gaeta at Cornell University, goes beyond the more familiar invisibility cloak, which aims to hide objects from view, by making entire events invisible.

Zeeya Merali in her extensive June 5, 2013 article (Temporal cloak erases data from history) for Nature provides an in depth explanation of the Purdue research,

To speed up the cloaking rate, Lukens and his colleagues exploited a wave phenomenon that was first discovered by British inventor Henry Fox Talbot in 1836. When a light wave passes through a series of parallel slits called a diffraction grating, it splits apart. The rays emanating from the slits combine on the other side to create an intricate interference pattern of peaks and troughs. Talbot discovered that this pattern repeats at regular intervals, creating what is now known as a Talbot carpet. There is also a temporal version of this effect in which you manipulate light over time to generate regular periods with zero light intensity, says Lukens. Data can be then be hidden in these holes in time.

Lukens’ team created its Talbot carpet in time by passing laser light through a ‘phase modulator’, a waveguide that also had an oscillating electrical voltage applied to it. As the voltage varied, the speed at which the light travelled through the waveguide was altered, splitting the light into its constituent frequencies and knocking these out of step. As predicted, at regular time intervals, the separate frequencies recombined destructively to generate time holes. Lukens’ team then used a second round of phase modulation to compress the energy further, expanding the duration of the time windows to 36 picoseconds (or 36 trillionths of a second).

The researchers tested the cloak to see if it was operating correctly by inserting a separate encoded data stream into the fibre during the time windows. They then applied two more rounds of phase modulation — to “undo the damage of the first two rounds”, says Lukens — decompressing the energy again and then combining the separated frequencies back into one. They confirmed that a user downstream would pick up the original laser signal alone, as though it had never been disturbed. The cloak successfully hid data added at a rate of 12.7 gigabits per second.

Unfortunately, the researchers were a little too successful and managed to erase the event entirely, which seems to answer a question I posed facetiously in my July 14, 2011 posting,

If you can’t see the object (light bending cloak), and you never saw the event (temporal cloak), did it exist and did it happen?

In addition to the military applications that Lukens imagines for temporal invisibility cloaks, Merali notes a another possibility in her Nature article,

Ironically, the first application of temporal cloaks may not be to hide data, but to help them to be read more accurately. The team has shown that splitting and recombining light waves in time creates increased periods in which the main data stream can be made immune to corruption by inserted data. “This could be useful to cut down crosstalk when multiple data streams share the same fibre,” says Lukens.

Gaeta agrees that the primary use for cloaking will probably be for innocent, mundane purposes. “People always imagine doing something illicit when they hear ‘cloaking’,” he says. “But these ways for manipulating light will probably be used to make current non-secret communication techniques more sophisticated.”

The research paper can be found here,

A temporal cloak at telecommunication data rate by Joseph M. Lukens, Daniel E. Leaird & Andrew M. Weiner. Nature (2013) doi:10.1038/nature12224 Published online 05 June 2013

This paper is behind a paywall. Fortunately, anyone can access my June 5, 2013 posting (Memories, science, archiving, and authenticity) which seems relevant here for two reasons. First, there’s a mention of a new open access initiative in the US which would make this research more freely available in the future with a proposal (there may be others as this initiative develops) called the Clearinghouse for the Open Research of the United States (CHORUS).  I imagine there would be some caveats and I notice that Nature magazine has signed up for this proposal. I think the second reason for mentioning yesterday’s post is pretty obvious, memory/erasing, etc.

Buildable, bendable, and biological; a kirigami-based project at Cornell University

A May 18, 2013 news item on Azonano highlights a new project at Cornell University,

Cornell researchers Jenny Sabin, assistant professor of architecture, and Dan Luo, professor of biological and environmental engineering, are among the lead investigators on a new research project to produce “buildable, bendable and biological materials” for a wide range of applications.

The project is intended to bring new ideas, motifs, portability and design to the formation of intricate chemical, biological and architectural materials.

Based on Kirigami (from the Japanese word kiru, “to cut”), the project “offers a previously unattainable level of design, dynamics and deployability” to self-folding and unfolding materials from the molecular scale to the architectural level, according to the researchers.

The May 16, 2013 Cornell University news release by Daniel Aloi, which originated the news item, describes the project’s intent,

The project is intended to illuminate new principles of architecture, materials synthesis and biological structures, and advance several technologies – including meta-materials, sensors, stealth aircraft and adaptive and sustainable buildings. A complementary goal is to generate public interest through an enhanced impact on science, art and engineering.

“Like the opening and closing of flowers, satellites and even greeting cards, our research will offer a rich and diverse set of intricate surprises, problems and challenges for students at all levels, and broaden their interest and awareness of emerging science and engineering,” according to the project proposal, “Cutting and Pasting: Kirigami in Architecture, Technology and Science” (KATS).

The Emerging Frontiers in Research Innovation grant from the NSF is in the research category of Origami Design for Integration of Self-assembling Systems for Engineering Innovation.

I wish they had a few sample illustrations of how this project might look as a macroscale architectural (or other type of) project even it is a complete fantasy.

Nanotechnology-enabled fashion at Cornell University

The image you see below is one of several featuring work from Cornell University’s Textiles Nanotechnology Laboratory,

Wearable Charging StationCredit: Textiles Nanotechnology Laboratory/Cornell UniversityAbbey Liebman, a design student at Cornell University in Ithaca, N.Y., created a dress made with conductive cotton that can charge an iPhone via solar panels.

Wearable Charging StationCredit: Textiles Nanotechnology Laboratory/Cornell University. Abbey Liebman, a design student at Cornell University in Ithaca, N.Y., created a dress made with conductive cotton that can charge an iPhone via solar panels.

It’s part of a May 7, 2013 slide show put together by Denise Chow at the LiveScience website. Also shown in the slide show are Olivia Ong’s anti-bacterial clothing (featured here in an Aug. 5, 2011 posting) and some anti-malarial clothing by Matilda Ceesay (featured here in a May 15, 2012 posting). I have more details about the textiles and the work but the pictures on LiveScience are better.

As I’ve not come across LiveScience before ,my curiosity was piqued and to satisfy it, I found this on their About page,

LiveScience, launched in 2004, is the trusted and provocative source for highly accessible science, health and technology news for people who are curious about their minds, bodies, and the world around them. Our team of experienced science reporters, editors and video producers explore the latest discoveries, trends and myths, interviewing expert sources and offering up deep and broad analyses of topics that affect peoples’ lives in meaningful ways. LiveScience articles are regularly featured on the web sites of our media partners: MSNBC.com, Yahoo!, the Christian Science Monitor and others.

Most of the science on LiveScience is ‘bite-sized’ and provides information for people who are busy and/or don’t want much detail.

Bioengineered ear at Cornell University

The researchers claim their bioengineered ear looks and acts like a real ear, from the Feb. 20, 2013 news release on EurekAlert,

Cornell bioengineers and physicians have created an artificial ear – using 3-D printing and injectable molds – that looks and acts like a natural ear, giving new hope to thousands of children born with a congenital deformity called microtia.

In a study published online Feb. 20 in PLOS ONE, Cornell biomedical engineers and Weill Cornell Medical College physicians described how 3-D printing and injectable gels made of living cells can fashion ears that are practically identical to a human ear. Over a three-month period, these flexible ears grew cartilage to replace the collagen that was used to mold them.

“This is such a win-win for both medicine and basic science, demonstrating what we can achieve when we work together,” said co-lead author Lawrence Bonassar, associate professor of biomedical engineering.

The novel ear may be the solution reconstructive surgeons have long wished for to help children born with ear deformity, said co-lead author Dr. Jason Spector, director of the Laboratory for Bioregenerative Medicine and Surgery and associate professor of plastic surgery at Weill Cornell in New York City.

“A bioengineered ear replacement like this would also help individuals who have lost part or all of their external ear in an accident or from cancer,” Spector said.

Replacement ears are usually constructed with materials that have a Styrofoam-like consistency, or sometimes, surgeons build ears from a patient’s harvested rib. This option is challenging and painful for children, and the ears rarely look completely natural or perform well, Spector said.

Lawrence Bonassar, associate professor of biomedical engineering, and colleagues collaborated with Weill Cornell Medical College physicians to create an artificial ear using 3-D printing and injectable molds. Credit: Lindsay France/University Photography [downloaded from http://www.news.cornell.edu/stories/Feb13/earPrint.html]

Lawrence Bonassar, associate professor of biomedical engineering, and colleagues collaborated with Weill Cornell Medical College physicians to create an artificial ear using 3-D printing and injectable molds. Credit: Lindsay France/University Photography [downloaded from http://www.news.cornell.edu/stories/Feb13/earPrint.html]

A Feb. 20, 2013 article in Cornell University’s Chronicle Online (and the basis for the news release) provides details about how this bioengineered ear was achieved (Note: A link has been removed),

To make the ears, Bonassar and colleagues started with a digitized 3-D image of a human subject’s ear and converted the image into a digitized “solid” ear using a 3-D printer to assemble a mold.

They injected the mold with collagen derived from rat tails, and then added 250 million cartilage cells from the ears of cows. This Cornell-developed, high-density gel is similar to the consistency of Jell-O when the mold is removed. The collagen served as a scaffold upon which cartilage could grow.

The process is also fast, Bonassar added: “It takes half a day to design the mold, a day or so to print it, 30 minutes to inject the gel, and we can remove the ear 15 minutes later. We trim the ear and then let it culture for several days in nourishing cell culture media before it is implanted.”

The incidence of microtia, which is when the external ear is not fully developed, varies from almost 1 to more than 4 per 10,000 births each year. Many children born with microtia have an intact inner ear, but experience hearing loss due to the missing external structure.

There was a show in 2004  at the Vancouver Art Gallery (Canada), Massive Change, curated by graphic designer Bruce Mau, which amongst many other objects and images featured a bioengineered nose being grown in a beaker. If memory serves, the work featuring the nose was from Israel and there was no mention of when that work might leave the lab and be used for implants. From the Chronicle article,

Bonassar and Spector have been collaborating on bioengineered human replacement parts since 2007. Bonassar has also worked with Weill Cornell neurological surgeon Dr. Roger Härtl on bioengineered disc replacements using some of the same techniques demonstrated in the PLOS One study.

The researchers specifically work on replacement human structures that are primarily made of cartilage — joints, trachea, spine, nose — because cartilage does not need to be vascularized with a blood supply in order to survive.

They are now looking at ways to expand populations of human ear cartilage cells in the laboratory so that these cells can be used in the mold, instead of cow cartilage.

“Using human cells, specifically those from the same patient, would reduce any possibility of rejection,” Spector said.

He added that the best time to implant a bioengineered ear on a child would be when they are about 5 or 6 years old. At that age, ears are 80 percent of their adult size.

If all future safety and efficacy tests work out, it might be possible to try the first human implant of a Cornell bioengineered ear in as little as three years, Spector said.

Good luck to them. For anyone who’s interested here’s a citation and link to the paper,

Reiffel AJ, Kafka C, Hernandez KA, Popa S, Perez JL, et al. (2013) High-Fidelity Tissue Engineering of Patient-Specific Auricles for Reconstruction of Pediatric Microtia and Other Auricular Deformities. PLoS ONE 8(2): e56506. doi:10.1371/journal.pone.0056506

PLoS One is an open access journal.

From Cornell University, a liquid that remembers its shape

Sometimes one experiences a frisson (shiver) when reading about a piece of research. Let’s see how you do with this Dec. 4, 2012 news item on Nanowerk,

A bit reminiscent of the Terminator T-1000, a new material created by Cornell researchers is so soft that it can flow like a liquid and then, strangely, return to its original shape.

Rather than liquid metal, it is a hydrogel, a mesh of organic molecules with many small empty spaces that can absorb water like a sponge. It qualifies as a “metamaterial” with properties not found in nature and may be the first organic metamaterial with mechanical meta-properties.

The Dec. 3, 2012 Cornell University news article by Bill Steele, which originated the news item,goes on to explain the interest in hydrogels and what makes this particular formulation so special,

Hydrogels have already been considered for use in drug delivery — the spaces can be filled with drugs that release slowly as the gel biodegrades — and as frameworks for tissue rebuilding. The ability to form a gel into a desired shape further expands the possibilities. For example, a drug-infused gel could be formed to exactly fit the space inside a wound.

The new hydrogel is made of synthetic DNA. In addition to being the stuff genes are made of, DNA can serve as a building block for self-assembling materials. Single strands of DNA will lock onto other single stands that have complementary coding, like tiny organic Legos. By synthesizing DNA with carefully arranged complementary sections Luo’s [Dan Luo, professor of biological and environmental engineering] research team previously created short stands that link into shapes such as crosses or Y’s, which in turn join at the ends to form meshlike structures to form the first successful all-DNA hydrogel. Trying a new approach, they mixed synthetic DNA with enzymes that cause DNA to self-replicate and to extend itself into long chains, to make a hydrogel without DNA linkages.

“During this process they entangle, and the entanglement produces a 3-D network,” Luo explained. But the result was not what they expected: The hydrogel they made flows like a liquid, but when placed in water returns to the shape of the container in which it was formed.

“This was not by design,” Luo said.

See the material for yourself,

Hydrogels made in the form of the letters D, N and A collapse into a liquid-like state on their own but return to the original shape when surrounded by water Provided/Luo Lab

Nature Nanotechnology published the team’s research online Dec. 2, 2012 and, unusually, the article is open access (at least for now),

A mechanical metamaterial made from a DNA hydrogel by Jong Bum Lee, Songming Peng, Dayong Yang,  Young Hoon Roh, Hisakage Funabashi, Nokyoung Park, Edward J. Rice, Liwei Chen, Rong Long, Mingming Wu & Dan Luo in Nature Nanotechnology  (2012) doi:10.1038/nnano.2012.211 published online Dec. 2, 2012

Depending on your reading interests and time available, Bill Steele’s Cornell University article has more detail than I’ve provided here or you can check out the well illustrated article in Nature Nanotechnology. As these things go, it’s quite readable as you can see with the abstract (Note: I have removed footnotes),

Metamaterials are artificial substances that are structurally engineered to have properties not typically found in nature. To date, almost all metamaterials have been made from inorganic materials such as silicon and copper, which have unusual electromagnetic or acoustic properties that allow them to be used, for example, as invisible cloaks superlenses or super absorbers for sound. Here, we show that metamaterials with unusual mechanical properties can be prepared using DNA as a building block. We used a polymerase enzyme to elongate DNA chains and weave them non-covalently into a hydrogel. The resulting material, which we term a meta-hydrogel, has liquid-like properties when taken out of water and solid-like properties when in water. Moreover, upon the addition of water, and after complete deformation, the hydrogel can be made to return to its original shape. The meta-hydrogel has a hierarchical internal structure and, as an example of its potential applications, we use it to create an electric circuit that uses water as a switch.

For anyone not familiar with the Terminator movies, here’s an essay in Wikipedia about the ‘franchise’. Pay special note to the second movie in the series, Terminator 2: Judgment Day which introduced a robot (played by Robert Patrick) that could morph from a liquidlike state into various lethal entities.

Cornell University (New York State, US) celebrates 35 years of nanotechnology research

The festivities at Cornell University start on July 19, 2012 according to the July 9, 2012 news item by Anne Ju for the Cornell Chronicle,

Photonics, magnetics, biotechnology and energy are just a few areas in which the Cornell NanoScale Science and Technology Facility (CNF) has spent more than three decades connecting the brightest researchers with the best tools and expertise to make their scientific ideas real.

On July 19, CNF will celebrate its storied history of cutting-edge nanoscience research and discovery at its 35th anniversary and annual meeting.

Speakers will include Michal Lipson, professor of electrical and computer engineering, who will talk about manipulating light on a chip; and Jordan Katine, of Hitachi Global Storage Technologies and former Cornell postdoctoral associate, who will describe promising methods for making nanoscale magnetic devices.

The event’s keynote speaker will be William Brinkman, director of the Office of Science in the U.S. Department of Energy, who will address “Whither Nanoscience?”

Over the years, thanks in part to CNF, Cornell has helped “nanotechnology” become a household word: In 1997, a Cornell student used electron beam lithography to etch a red blood cell-sized guitar onto a silicon chip, a feat that garnered worldwide attention.

Cornell and CNF have stayed on the leading edge of nanoscale science. For example, in the last year, a low-pressure chemical vapor deposition machine for making graphene and carbon nanotubes was purchased through a grant, said Donald Tennant, CNF director of operations.

More than 700 researchers use CNF every year, and about half come from outside Cornell. A key goal of CNF is to have a low-overhead, open-access operating model and to level the playing field for researchers with limited resources, Tennant said.

You can find out more about the July 19, 2012 CNF event here. As for an opening address titled, Whither nanoscience? Doesn’t the word ‘whither’ give the address an old-fashioned flavour, something from the 19th century or perhaps from the bible (Whither thou goest, I will go [Ruth to Naomi])?

Meanwhile, on  July 20, 2012 there will be a special media briefing by Cornell and Stanford University (California) nanoscience researchers, from the July 13, 2012 news item on the Nanotechnology Now website,

On Friday, July 20, from 10 to 11 a.m. [EST], a special panel of nantechnology researchers will gather at Cornell University and explore the future of nanoscience during an interactive conversation with members of the media – both on site in Ithaca and online from anywhere in the world via WebEx technology.

Joining journalists for the discussion will be:

  • Juan Hinestroza, an associate professor fiber science, directs the Textiles Nanotechnology Laboratory at Cornell’s College of Human Ecology. His research on understanding fundamental phenomena at the nanoscale that are relevant to fiber and polymer science, has led to breakthrough “multifunctional fibers” that can hold or change color, conduct and sense micro-electrical currents, and selectively filter toxic gasses.
  •  ….

Media members are invited to take part, in person or online. To do so, please RSVP to John Carberry in Cornell’s Press Relations Office at 607-255-5353 or [email protected]

I last mentioned Juan Hinestroza in connection with work done by his students at Cornell University with textiles that give protection from malaria in a May 15, 2012 posting.

Textiles to offer protection from malaria and more about nanotechnology-enabled textiles

Textiles that harvest our energy to recharge the batteries for phones and other portable devices (for example, US Army research in my May 9, 2012 posting and British soldiers prepare to conduct field tests in my April 5, 2012 posting), that protect us from poison gases (my page on nanotechnology and textiles on the Nanotech Mysteries wiki), that clean pollution from the air (my Feb. 24, 2012 posting about Catalytic Clothing), and more  are currently being developed. It seems textiles used for passive protection and decoration and other forms of personal enhancement (body shapers, ‘lifts and separates’)  are becoming more active. One of the latest developments is a textile that protects from malaria. From the May 8, 2012 news item on Nanowerk,

A Cornell University scientist and designer from Africa have together created a fashionable hooded bodysuit embedded at the molecular level with insecticides for warding off mosquitoes infected with malaria, a disease estimated to kill 655,000 people annually on the continent.

Though insecticide-treated nets are commonly used to drive away mosquitoes from African homes, the Cornell prototype garment can be worn throughout the day to provide extra protection and does not dissipate easily like skin-based repellants. By binding repellant and fabric at the nanolevel using metal organic framework molecules – which are clustered crystalline compounds – the mesh fabric can be loaded with up to three times more insecticide than normal fibrous nets, which usually wear off after about six months.

“The bond on our fabric is very difficult to break,” said Frederick Ochanda, postdoctoral associate in fiber science and apparel design (FSAD) in the College of Human Ecology and a native of Kenya. “The nets in use now are dipped in a solution and not bonded in this way, so their effectiveness doesn’t last very long.”

I’m assuming that this design will be reworked to accommodate more average bodies (from Cornell University’s  ChronicleOnline April 30, 2012 article by Ted Boscia,

Sandy Mattei models a design by Matilda Ceesay '13, an FSAD apparel design major from Gambia, at the Cornell Fashion Collective spring fashion show April 28 on campus. Credit: Mark David Vorreuter

Boscia gives details,

The colorful garment, fashioned by Matilda Ceesay ’13, an FSAD apparel design major from Gambia, debuted at the Cornell Fashion Collective spring fashion show April 28 [2012] on campus. It consists of an underlying one-piece bodysuit, hand-dyed in purple, gold and blue, and a mesh hood and cape containing the repellant. The outfit is one of six in Ceesay’s collection, which she said “explores and modernizes traditional African silhouettes and textiles by embracing the strength and sexuality of the modern woman.”

Ceesay and Ochanda, who works with FSAD Associate Professor Juan Hinestroza, partnered with Laurie Lange, graduate student in Professor Kay Obendorf’s lab, to refine the process for capturing insecticides on the MOF-coated cloth. Hinestroza called the resulting garment “fashionable and functional, with the potential to create a new generation of durable and effective insecticide mosquito protection nets.”

The researchers are not pinning all of their hopes on the body suit (from Boscia’s April 30, 2012 article),

Ultimately, Ceesay and Ochanda hope the outfit they developed will serve as a prototype to drive new technologies for fighting the spread of malaria. On the horizon, Ochanda said, is an MOF fabric that releases repellant in response to changes in temperature or light — offering wearers more protection at night when mosquitoes are on the hunt. At minimum, they hope the technology can be applied to create longer lasting insecticide-laden bed nets.

Despite the use of mosquito nets, “people are still getting sick and dying,” Ceesay said. “We can’t get complacent. I hope my design can show what is possible when you bring together fashion and science and will inspire others to keep improving the technology. If a student at Cornell can do this, imagine how far it could go.”

Both the designer and scientist have a very personal stake in creating textiles that will repel malaria-borne mosquitoes (from Boscia’s article),

Ochanda and Ceesay, from opposite sides of the continent, both have seen family members suffer from the disease. Its prevalence in Africa — the source of 90 percent of the world’s malaria infections annually — can also lead to harmful misdiagnoses. Ceesay recalls a family member who died after doctors treated her for malaria when she had a different sickness. “It’s so common back home; you can’t escape it,” Ceesay said.

“Seeing malaria’s effect on people in Kenya, it’s very important for me to apply fiber science to help this problem,” Ochanda added. “A long-term goal of science is to be able to come up with solutions to help protect human health and life, so this project is very fulfilling for me.”

There’s no mention of how close this textile is to becoming a product and being offered in the marketplace. So, for anyone who’s generally interested in nanotechnology-enable textiles and possible economic impacts and business outlooks, Cientifica released its report, Nanotechnologies for Textile Markets in April 2012 (available for purchase). From the April 16, 2 012 news release and report description webpage,

While the traditional markets of apparel and home textiles continue to be impacted by nanotechnologies, especially in adding value through finishing and coating, the major opportunities for both textile manufacturers and nanomaterial suppliers lie elsewhere.

“Nanotechnologies for the Textile Market” takes an in depth look at the major textile markets – apparel, home, military, medical, sports, technical and smart textiles – detailing the key applications of nanotechnologies and the major players. The 255 page report contains  full market analyses and predictions for each sector to 2022, outlines the key opportunities and is illustrated with 98 figures and 30 tables.

Cientifica predicts that the highest growth over the next decade will be seen in the areas of smart and technical textiles.  In both of these areas a significant part of the added value is due to the innovative use of nanotechnologies, whether in fiber production or as a coating or additive.

With over a billion Bluetooth enabled devices on the market, ranging from smartphones to set top boxes, and new technologies such as energy scavenging or piezoelectric energy generation being made possible by the use of nanotechnologies , there are opportunities for the textile industry in new markets ranging from consumer electronics to medical diagnostics.

‘It’s a perfect storm” added Tim Harper [Cientifica's Chief Executive Office], “the availability of new materials such as graphene, the huge leaps being made in organic electronics, and the move towards the Internet of Things is blurring the divide between textiles and electronic devices. When two trillion dollar markets collide there will be lots of disruption and plenty of opportunities.”

Cientifica does offer a free download of the report’s Table of Contents (ToC). Here’s a sample from the ToC which gives you a preview  of the report’s contents,

EXECUTIVE SUMMARY  11
INTRODUCTION  21
Objectives of the Report  21

World Textiles and Clothing  22
Overview of Nanotechnology Applications in the EU Textile Industry  24
Overview of Nanotechnology Applications in the US Textile Industry 25
Overview of Nanotechnology Applications in the Chinese Textile Industry  26
Overview of Nanotechnology Applications in the Indian Textile Industry  27
Overview of Nanotechnology Applications in the Japanese Textile Industry  27
Overview of Nanotechnology Applications in the Korean Textile Industry  29
Textiles in the Rest of the World 31
Macro and Micro Value Chain of Textiles Industry  32
Common Textiles Industry Classification  32
End Markets and Value Chain Actors 32
Why Textiles Go Nano 34
Nanotechnology in Textiles 34
Nanotechnology in Some Textile-related Categories 37
Technical & Smart Textiles 37
Multifunctional Textiles 39
High Performance Textiles 39
Smart/Intelligent Textiles 39
Nanotechnology Hype 41
CURRENT APPLICATIONS OF NANOTECHNOLOGY IN TEXTILE PRODUCTION  43
Nanotechnology in Fibers and Yarns 43

Nanotechnology in Fabrics 47

Nanotechnology in Textile Finishing, Dyeing and Coating 55

Nanotechnology In Textile Printing 66
Green Technology — Nanotechnology In Textile Production Energy Saving 67

Electronic Textiles 67

Concept  67
Markets and Impacts 68
Current E-Textile Solutions and Problems 69
Nanotechnology in Electronic Textiles 78
Future and Challenges of Electronic Textiles  87
NANOTECHNOLOGY APPLICATIONS IN CLOTHING/APPAREL TEXTILES 89
Summary of Nanotechnology Applications in Clothing/Apparel Textiles 90
Current Applications of Nanotechnology in Clothing/Apparel Textiles 91
Hassle-free Clothing: Stain/Oil/Water Repellence, Anti-Static, Anti-Wrinkle 91

The Guardian newspaper in an October 4,  2011 article by Colin Stuart offers a brief , comprehensive but cautionary overview of nanotechnology-enabled textiles (thanks for the tip, Tim Harper),

The manipulation of textiles is an age-old practice, starting with the furs of the animals we hunted. As agriculture and farming grew, we began to weave natural fibres, providing us with fabrics such as cotton and wool – sartorial staples we’ve relied on for centuries.

Unsurprisingly, the most mainstream use of nanotextiles is in clothing. The chances are you have some nanotextiles hanging in your wardrobe; wrinkle-free or non-iron garments have been engineered against creasing by coating the fibres with nanoparticles. Nanotechnology is also responsible for the stain-resistant fabrics found in both clothing and carpets. Tiny, nano-sized hairs are added to the surface of the material which stop liquids from being absorbed. …

The nano clothing of the future, however, could add even more functionality to the latest fashions. Tomorrow’s must-wear materials could hide piezoelectrics – nanotechnology that harvests the energy created as you rub against the fabric. Imagine walking along as your every move helps charge an iPod strapped to your belt.

But nanotextiles are not just confined to clothing; they are also being used in Asia in the battle against malaria. In 2010 a group of Thai researchers announced they had created mosquito nets laced with nanoparticles of pyrethroid, an insecticide. Pyrethroid had been combined with nets before, but doing so on the nanoscale means the particles are small enough to cling to the fibres even when washed. These nano-nets can last up to five years – a five-fold improvement on conventional netting.

The article goes on to establish concerns over environmental, health, and safety regulations but I thought it best to end with the mosquito nets and malaria, which is where this posting started, more or less.