Slippery Polymer Gets Less Adhesive

May 21, 2013 By Leave a Comment

When Teflon pans came out in 1961, they were a big improvement over iron skillets. They were much easier to cook with, as foodTeflon virtually slipped out of the pan with very little lost because of sticking the skillet. And cleanup was so much faster and easier.

Now, researchers at the University of Arkansas have made the material — also known as polytetrafluoroethylene (PTFE) — even less sticky. This development could not only be good news for all those gourmet chefs out there, but also makers of medical devices or manufacturers that need to reduce friction in moving parts. The researchers’ work may help machinery last longer and operate more efficiently, reports Phys.Org.

“Polytetrafluoroethylene is a big, scary word,” says Min Zou, an associate professor of mechanical engineering at the university who supervised the development. “What we’re talking about here is a material layer or coating — a film — that essentially does not stick and is hydrophobic, meaning it repels water.”

PTFE is a solid lubricant and is appealing to manufacturers because it performs well in high temperatures, has low maintenance costs, and is clean compared to liquids. Phys.Org explains its other advantages and recent attempts to improve its non-sticky qualities:

It has been used as a lubrication polymer for many years, and recently scientists and engineers have attempted to improve the material by incorporating nanoparticle ‘fillers’ that reduce wear on the material and thus extend its life. However, high concentrations of these nano-fillers have created a problem: while reducing wear, they have also increased the material’s ability to create friction.

“A great obstacle in micro- and nanocomposite films has been the inability to find a filler material that provides good wear resistance as well as a low coefficient of friction,” Zou says. But Zou and her team found the secret material that is tough, yet slippery: silica.

She and her graduate student assistant applied thin films of silica to stainless steel. Then they tested it with varying degrees of friction and wear resistance. They performed the same tests on a pure PTFE film and then on bare stainless steel.

The results showed that silica was the key new ingredient. “Micrographs revealed that the composite films with higher concentration of silica had much narrower wear tracks after the samples were subjected to rubbing tests,” Zou says.

Polymer Solutions (PSI) is a full-service testing laboratory that can tell manufacturers the composition of various products made with polymers, plastics, and adhesives. Here is an example of what it does.

Source: “Research improves dry lubricant used in machinery and biomedical devices,” Phys.Org, 5/17/13
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ISO Certification Process Is Worth the Effort

May 16, 2013 By Leave a Comment

It takes a lot of effort to earn, but those who have it believe that it’s worth it to them and to their clients.

We’re talking about the ISO 17025 certification. The International Organization for ISO certificationStandardization certificate ensures that laboratories that prepare testing and calibration reports have the procedures in place to consistently produce valid results. A prerequisite for a lab to earn a certification is to have a documented quality management system.

Exact Scientific Services is one of the few testing laboratories in Washington state that has ISO 17025 certification. It took some work to obtain the classification, but CEO and Laboratory Director Kent Oostra says it was worth the effort, reports Food Safety News.

Oostra sees the silver lining in effort to get the certification. The ISO mandate for precise testing results in the lab minimizing risk, helps reduce or eliminate the need for retesting, and helps customers build confidence in the testing industry. “All of this reduces costs, improves acceptance, and positively impacts the bottom line,” he says.

Food Safety News explains further the requirements for certification:

Indeed, ISO 17025 looks at a laboratory’s ability to produce precise and accurate tests. ISO evaluates the technical competence of the staff, validity of test methods, traceability of the testing, quality assurance of data and the testing environment, and suitability, calibration and maintenance of test equipment. And to ensure continued compliance, accredited laboratories are audited on a yearly basis to check that they are maintaining their technical expertise.

“We uncovered a number of surprising benefits for our clients through ISO certification,” Oostra says. “Our clients are telling us that ISO provides peace of mind during internal audits, as well as assurances for their customers.”

One client, Mike Kaminski, director of quality assurance, at Barleans Organic Oils, says the ISO accreditation “helps us when we have internal audits and they ask us if our lab has certifications. The ISO speaks volumes and helps us a lot.”

Another client at Enfield Farms agrees. “ISO is gaining in importance in our audits,” says Laura Macaulay, quality assurance manager. “A third-party lab negates the potential for conflict of interest, and an ISO certified lab negates any concerns for testing procedures.”

The fact that ISO certification is internationally recognized gives accredited laboratories a form of international recognition. Their tests can then be more readily accepted. “We don’t need to get products double tested in different markets to accommodate regional requirements,” says another Exact client.

Polymer Solutions (PSI) is ISO 17025 accredited as well. PSI is often called upon by manufacturers to find contaminants in products or determine why the quality of a product has been compromised. Here are 25 surprising examples.

Source: “The Rising Importance of ISO Certification,” Food Safety News, 5/10/13
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New Method Gives Rise to Chemical Innovation

May 14, 2013 By Leave a Comment

It may not be alchemy — turning lead into gold — but it could turn every day things into something more valuable.

In metathesis, chemical bonds are broken and new ones are formed. In olefin olefin metathesismetathesis, a catalyst will enable a double-bonded atomic group to change places with another. It has long been possible to make new substances in these reactions, but not much was known how those catalysts function.

Chemists, who solved that puzzle, won a Nobel Prize in 2005, and now we can produce valuable products with organic molecules — such as pharmaceuticals and coatings — that were undreamed of a few years ago, according to a website of a company that taps into the new technology.

It’s not surprising, then, that industries believe that there is a bright future in using this method for developing polymers with special characteristics. The chemists’ catalytic breakthrough has lead to a new synthesis of insect pheromones, herbicides, fuel additives, and drugs to treat a wide range of medical problems, such as bacterial infections, cancer, Alzheimer’s arthritis, and HIV/AIDS.

One company, Elevance Renewable Sciences, based in Woodridge, IL, leverages olefin metathesis to produce engineered polymers and coatings from renewable oils for specialty products. Because the method cuts out many of the steps traditionally used to manufacture these products, it saves energy and cuts greenhouse gas emissions by up to 50% compared to petrochemical technologies, the company says. The method allows the company to make products that expand options for manufacturers of specialty polyamides and polyesters; produce novel epoxides and polyurethanes; and create renewable products with varying degrees of unsaturation and molecular weight.

The company won EPA’s Presidential Green Chemistry Challenge Award last year. The honor was established to recognize innovative chemical technologies that prevent pollution and have broad applicability in industry. Elevance has been working with Jim Jones, acting assistant administrator for the agency’s Office of Chemical Safety and Pollution Prevention, to promote cleaner technologies.

“Elevance is impressed with the initiative and leadership that the EPA and Jim Jones are demonstrating in support of green chemistry,” says K’Lynne Johnson, CEO of Elevance. “An efficient and effective regulatory review process is critical to commercializing innovative new chemicals that can provide improved products for consumers, new jobs from the emerging renewable chemicals industry and environmental benefits for everyone.”

Other companies are using renewable techniques to produce valuable products that have minimal environmental impact. For example, Dutch chemical company, AkzoNobel, has teamed with renewable oil and bioproducts company Solazyme to produce renewable oil from algae. The goal of the project is to produce oils that can enhance or replace petroleum-derived chemicals, and improve upon the performance of plant oils and animal fats, reports Environmental Leader.

Source: “Metathesis,” Elevance
Source: “Elevance Renewable Sciences, U.S. Environmental Protection Agency Host Green Chemistry Event in Woodridge, Illinois,” Elevance, 11/8/12
Source: “AkzoNobel Paint to Use Renewable Oils,” Environmental Leader, 5/9/13
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A Food Can Help Its Own Packaging

May 9, 2013 By Leave a Comment

A material that could keep food fresher and make food packaging more environmentally friendly might come from a food itself.

A European project is leveraging the qualities of chitin and chitosan from food packagingshrimp shells to conserve food wrapped in plastic. Then, after its use, the packaging biodegrades, reports a news release from Nofima, a food research institute in Norway.

Nofima will receive about $171,300 over two years to study how the shrimp shell materials can improve packaging. Chitin, a polymer, is a derivative of glucose that is often found in hard natural surfaces, such as shells. Chemically modified versions of it are used in the food processing industry to form edible films and to stabilize and thicken food. Chitosan is produced when shells are treated with an alkali sodium hydroxide; the linear polysaccharide is known for its ability to help plants fight off fungal infections.

Morten Sivertsvik, director of research at Nofima’s Department for Processing Technology, says:

Our job is to ensure food contact safety in the project and quantify the effect on bacteria. Chitosan used as an integrated part of the packaging can have an antibacterial effect on the food products. The EU has strict regulations in this area, and our role is to see that the active packaging have a positive and not negative impact on the food products. The chitosan-based fibers that are used in the packaging are based on nanotechnology, so we are talking about minute particles that by no means have to break down so they come in the food products.

Food and beverages account for about two-thirds of global packaging. Half of that is made from non-biodegradable material, much of which can litter the environment. Also, much of the plastics in packaging is made from petrochemicals, which have a relatively low environmental factor and produce carbon dioxide.

Bioplastics offer a promising alternative. For example, chitosan waste weighs 25 billion tons a year. Recycling it into something more useful would improve resource efficiency.

A research institute in Prague was granted a patent on a nanofiber made of chitin, which created new possibilities for chitin as an ingredient in biopolymers to replace plastic. The news release explains further how the biopolymers are useful:

The products range from hard bioplastic, which is just as robust as other plastics, to thin film that can come in direct contact with food products. The aim of the Chitopack project is to expand on the positive properties of chitin nanofibre in the development of new food packaging. The packaging is biocompatible, 100 percent naturally biodegradable and satisfies EU requirements for small and medium-sized enterprises.

On this side of the Atlantic, food packagers need to consider the impact of the “Green Guides,” which were issued by the Federal Trade Commission late last year, reports Food Safety Magazine. They provide guidance to marketers regarding claims they can make about their products’ environmental effects or product packaging. The purpose of the guides, which do not have the force of law, are to steer companies away from making claims that are deceptive.

Source: “From skin lotion to environmental packaging,” Nofima, 5/2/13
Source: “A Trial Lawyer’s Guide to the New FTC Green Labeling Guidelines,” Food Safety Magazine, 5/7/13
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Polymeric Nanofiber Is Tough and Strong

May 7, 2013 By Leave a Comment

polymer acrylicWe might be able to build tougher airplanes, stronger bridges, and harder body armor, thanks to the research conducted by materials engineers at the University of Nebraska-Lincoln. Yuris Dzenis, professor of mechanical and materials engineering, and his team at the university developed an unusually thin polyacrilonitrile nanofiber — a kind of a synthetic polymer similar to acrylic — by using a process called electrospinning, reports Next Big Future.

As the website explains, the researchers found that the process produced a counterintuitive result:

The process involves applying high voltage to a polymer solution until a small jet of liquid ejects, resulting in a continuous length of nanofiber. They discovered that by making the nanofiber thinner than had been done before, it became not only stronger, as was expected, but also tougher.

“Whatever is made of composites can benefit from our nanofibers,” Dzenis says in a news release from the university. “Our discovery adds a new material class to the very select current family of materials with demonstrated simultaneously high strength and toughness.”

The toughness probably comes from the nanofiber’s low crystallinity. The molecules are structurally unorganized so there’s room for them to move around, allowing the material to absorb energy.

Toughness is a measure of how well a material absorbs energy without breaking. A ceramic plate, for example, is strong because it can carry heavy loads, but it isn’t tough because if dropped, it would not absorb the energy of the impact well and shatter. A rubber ball, on the other hand, is not strong because its shape can be easily changed. But it is tough because it won’t easily break.

Similar recent research has shown that electrospun polymer nanofibers can be strengthened even if their diameter is reduced. However, their toughness has not been analyzed.

Dzenis and his team found that a reduction in the fiber’s diameter from 2.8 microns to 100 nanometers resulted in its elasticity from 0.36 to 48 GPa. Its strength increased from 15 to 1,750 MPa, and its toughness increased from 0.25 to 605 MPa. GPa (gigapascal) and MPa (megapascals) are units of measure common in materials science and have largely replaced pounds per square inch (psi). Six hundred MPa is roughly equivalent to 87,000 psi.

“If structural materials were tougher, one could make products more lightweight and still be very safe,” Dzenis says. He thinks his innovation will improve protective materials, such as body armor. “To stop the bullet, you need the material to be able to absorb energy before failure, and that’s what our nanofibers will do,” he says.

Source: “Polyacrylonitrile nanofibers 1750 MPa strong and 605 MPa tough,” Next Big Future, 4/25/13
Source: “UNL team’s discovery yield supertough, strong nanofibers,” University of Nebraska-Lincoln, 4/23/13
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Bioengineered Windpipe Implanted Into Toddler

May 2, 2013 By Leave a Comment

A two-and-a-half-year-old girl is the youngest person to have received a bioengineered organ — a windpipe in this case — that was made from plastic fibers and human cells.

The successful transplant of the synthetic windpipe on the girl, a Korean-regenerative medicineCanadian named Hannah Warren, may give regenerative medicine a huge boost. The surgery, which took nine hours at Children’s Hospital of Illinois in April, has occurred only six times. It was the first occurrence in the United States, and received approval from the U.S. Food and Drug Administration (FDA) under rules that allow experimental procedures when the patient has little chance of survival, reports The New York Times.

“Hannah’s transplant has completely changed my thinking about regenerative medicine,” says Dr. Paolo Macchiarini, a surgeon at the Karolinska Institute in Stockholm, who performed the surgery and developed the windpipe. Now that the operation is over, he wants to proceed with clinical trials in the United States that many say are needed to determine how effective these implants are.

Regenerative medicine, also called tissue engineering, creates new tissues and organs when there are transplant shortages, or when there is no other effective cure. Only because there have been recent advances in the understanding of the role that stem cells play in the process has there been any progress.

Until Hannah, the youngest recipient of a bioengineered organ was a 4-year-old spina bifida patient who received a bladder. The New York Times explains further how her windpipe was fashioned:

Dr. Macchiarini’s team made a half-inch diameter tube out of plastic fibers, bathed it in a solution containing stem cells taken from the child’s bone marrow and incubated it in a shoebox-size device called a bioreactor. Doctors are not sure exactly what happens after implantation, but think that the stem cells signal the body to send other cells to the windpipe, which then sort out so the appropriate tissues grow on the inside and outside of the tube. Because the windpipe uses only the child’s own cells, there is no need for drugs to suppress the patient’s immune system to avoid rejection of the implant.

Hannah was born with an extremely rare condition that is eventually fatal in about 99% of cases. Her engineered trachea will probably need to be replaced as she grows, in about four years. Her doctors tried to delay that replacement for as long as they could by making the implant larger than it needed to be now, and including some biodegradable plastic, which may allow it to stretch.

Dr. David Warburton, director of the regenerative medicine program at the Saban Research Institute, who was not involved in Macchiarini’s windpipe development, says he has guarded optimism about these bioengineered tissues. “The challenges will be making a wind pipe that functions better than a temporary fix,” he says.

Source: “Groundbreaking Surgery for Girl Born Without Windpipe,” The New York Times, 4/30/13
Image by OSF Saint Francis Medical Center, Peoria, Illinois.  Jim Carlson, Photographer, used with permission.

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Light Helps Design Polymer Circuits

April 30, 2013 By Leave a Comment

Photovoltaic materials could be made thinner, more efficient, and more stable thanks to a discovery from scientists in London.

The researchers at Imperial College London discovered a new way to position polymer solar cellnanoparticles in plastics. The method uses a combination of heat, and low-intensity visible and UV light to arrange the nanoparticles in patterns, reports Energy Harvesting Journal. The researchers believe that in the future the development will provide a low-cost tool to build thin-film circuits on 3-D printers.

The development may be particularly helpful for fullerene-polymer solar cells. These cells have many applications, including low-power wireless sensor networks that can monitor ocean temperatures and the stress inside a car engine. Engineers and designers like them because they are lightweight, inexpensive to make, flexible and can be manipulated at the molecular level. But they are notorious for being inefficient and unstable.

The researchers wanted to see how light plays a role in the stabilization of these films. So, conducting neutron reflectometry experiments at the Institut Laue-Langevin, an internationally-financed scientific facility in Grenoble, France, the researchers “shaved” layers off the films to see what happens to fullerene and the polymers separately on an atomic scale.

Energy Harvesting Journal explains more about the experiments:

Whilst previous theories suggested that thin film stabilization was linked to the formation of an expelled fullerene nanoparticle layer at the substrate interface, neutron reflectometry experiments showed that the fullerenes remain evenly distributed throughout the layer. Instead, the team revealed that the stabilization of the films was caused by a form of photo-crosslinking of the fullerenes. The process imparts greater structural integrity to films, which means that ultrathin films, (down to 10000 times smaller than a human hair) readily become stable with trace amounts of fullerene.

The finding would allow for thinner plastic devices, which means there would be shorter distances that signals would have to travel to electrodes. This structural development would lead to increased efficiencies and longer lifetimes.

Light sensitivity also means that circuit patterns can be written onto the films. The research team used a photomask to control the distribution of light and added heat. Both made the fullerenes self-assemble into well-defined patterns that then could be into circuits with 3-D printers.

“Using just light, we can ask specific parts of the film to segregate or connect, stabilize and function for photovoltaic purposes,” says Dr. Joao Cabral of Imperial College London. “After this, it is not difficult to create on-demand, self-assembling complex patterns on these films by the simple addition of heat. If replicated for more complex compositions, this would represent a major advance in their commercial application in electronics as well as in energy harvesting of low power sources.”

Source: “A new low cost tool for 3D circuit printing?,” Energy Harvesting Journal, 4/23/13
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New Method in Polymer Chromatography

April 25, 2013 By Leave a Comment

As polymers become more complex, traditional separation techniques used to analyze the material’s composition are no longer adequate for today’s research and development demands.

But a Massachusetts lab instrument business owner, who helped build a refractometerchromaphotography 50 years ago, and Dow Chemical Company have teamed up to develop a system that they say can provide polymer analyses five to 20 times faster than traditional methods, reports Laboratorytalk. The system characterizes low- to mid-range molecular weight polymers that have begun to dominate product development processes.

Current analytical systems can be speedy but they produce less information. Jim Waters — the lab instrument business owner — and Dow claim that their new ACQUITY Advanced Polymer Chromatography (ATC) system, which was unveiled at a laboratory science equipment conference (Pittcon) in Philadelphia in March, does not make this compromise.

“Industry is on a constant quest to identify and understand the properties of new materials while making the process of innovation faster, simpler and more sustainable,” says Dow Chemical’s Jim Alexander, associate research and development director of Core R&D Analytical Sciences. “This new capability will help solve critical R&D challenges, helping scientists to drive to solutions more quickly, with improved data quality.”

Chromatography uses laboratory techniques to separate mixtures. The goal is to separate the components of a mixture for more advanced use. The process also measures the relative proportions of the components in the mixture. Testing laboratories often use this method to determine whether there is a contaminate in a product.

Laboratorytalk explains further how the APC system performs its analysis:

The ACQUITY APC system is comprised of a refractive index detector that has been optimised for low dispersion but with the low noise and drift performance required for accurate integration, even at low polymer concentrations. Flow stability is the most important contributor to accurate molecular weight. Calibration of a bank of columns is based on the elution time of the polymers. The long-term flow stability of the APC ensures calibration provides the right molecular weight data for the polymer.

The system has a technology based on tiny, high-pore volume, bridged-ethyl hybrid particles that help make the separations faster. The technology’s chemistries are not polymeric gel-based and thus do not swell in different solvents needed for polymer analysis.

The move away from a soft-gel technology should improve laboratory efficiency, says Ian King, a vice president of Waters’ company, Separations Technology. “With APC, scientists can run diverse polymer applications on a single system,” he says.

Source: “A new era in polymer discovery,” Laboratorytalk, 4/18/13
Image by Andra Mlhali.

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Synthetic Polymer Relieves Knee Pain

April 23, 2013 By Leave a Comment

polymer lubricant

As anyone with chronic knee pain will attest, being mobile in order to perform even the simplest tasks can be excruciating and frustrating. But thanks to research conducted by scientists at Boston University, people with knee pain and arthritis may soon get pain relief. Or even stave off total knee replacement surgery.

The researchers developed a synthetic polymer that could act as a lubricant for joint cartilage. The polymer — poly(7-oxanorbornene-2-carboxylate) — has a high molecular weight and does not break down like other currently used lubricants, reports Chemistry World.

Mark Grinstaff, professor of biomedical engineering at Boston University, and his team got inspiration for the lubricant in the way that many other ideas come about: seeing how a breakthrough in one area can be used in another area. Chemistry World explains the foundation of the Eureka moment:

The polymer has carboxylate side groups, and so is chemically similar to hyaluronic acid, which is a natural carbohydrate-based polymer that makes up part of the synovial fluid that helps lubricate articular joints like knees. A few years ago, Grinstaff explains, the group worked out some tweaks to the ring-opening metathesis polymerisation (ROMP) reaction that they were using to make their polymer. This allowed them to make much longer chains.

“Instead of having molecular weights of 1–200,000, we could get up to 2.5 million,” he says. “When the polymers get that large, the rheological properties change — we noticed when we dissolved them in water they were slippery to the touch.”

The slipperiness gave the researchers the idea that the new polymer could be a good lubricant for people with joint pain or osteoarthritis. The lubricant would need to be injected into the joint.

These types of lubricants have been on the market for about 10 years. They have mixed reviews as to their effectiveness — some people say that they work and others say that they don’t. But they usually require repeated periodic injections.

Grinstaff believes that his lubricant will stay in the joint longer — and therefore provide benefits longer — because of the high molecular weight. Its composition does not get broken down by enzymes present in the synovial fluid.

The synthetic polymer has received cautious praise from other researchers. “It’s an interesting approach,” says Philippa Cann from Imperial College London. However, she believes that the polymer needs to be tested under more physiologically relevant conditions.

For example, Grinstaff’s team has performed some experiments using the polymer on human cartilage taken from cadavers. But Cann points out that there’s a difference between dead tissue and where synovial fluid is present. “It’s important to understand what kind of interactions the polymer might have with what’s already in the joint,” she says.

Source: “Polymer lubricant may stave off knee surgery,” Chemistry World, 4/15/13
Image by Nevit Dilmen.

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Parasitic Worm’s Hooks Model for Better Adhesives

April 18, 2013 By Leave a Comment

Thank you, spiny-headed parasitic worms. We are improving the ability of bandages to stay on wet, living tissue because of you.

“There’s a huge unmet medical need for better adhesives, to patch leaks in adhesiveplaces where they can be catastrophic,” says bioengineer Jeffrey Karp, co-director of the Center for Regenerative Therapeutics at Brigham and Women’s Hospital in Boston, who is using the physical characteristics of a spiny-headed parasitic worm to make better adhesives. Bandages have a hard time staying on wet, oozing wounds.

The methods available to solve this problem have drawbacks, reports TechNewsDaily. Chemical adhesives, for example, can create toxic byproducts, such as a formaldehyde, and then don’t close or seal set tissues and adhere only to certain tissues. Stitches close wounds but are not best suited in tiny spaces or on soft, thin tissue. Staples also close wounds well but can cause tissue damage and scarring, and are prone to cause infection in the holes they make in tissue.

To find a better alternative, Karp was inspired by nature. “Nature has figured out ways to overcome significant barriers to achieve strong levels of adhesion in quite challenging environments,” he says [link added].

Nature has the spiny-headed parasitic worm, also known as Pomphorhynchus laevis. These animals are known for their protrudible proboscis that is often covered with spiny hooks, like cactus tips, arranged in horizontal rows. The worm uses those hooks to anchor itself within the intestines of fish.

Using those worms’ hooks as a model, Karp designed an adhesive patch with thousands of microscopic cone-shaped needles that are about 280 microns wide — close to three times the width of a human hair — and 700 microns in length. TechNewsDaily explains further how the needles work in tissue:

The needles each have a stiff inner core made of polystyrene, which is typically found in plastic bottles, and an outer layer made of a mix of polystyrene and the water-absorbent hydrogel found in diapers. The needle tips can swell up to two or three times their original sizes when wet — as such, when a bandage covered with such needles is pressed against moist living tissue, the needles penetrate the surface and swell up, locking into place.

The microneedles hurt a tiny bit upon application, Karp says. But what about getting the bandage off? Is it more pain-free to slowly and carefully take it off, or should one give it a good yank and get it over with quickly?

Karp says getting the bandage off is like peeling off duct tape, after testing it on his own finger. He adds:

The holes they make are so small that they can close really quickly on removal — within an hour, I couldn’t even tell it was once there. The materials are strong enough to remain secure when swollen within tissue, yet weak enough that they can deform and pull out through the initial holes they made. Also, the fact that they swell up to fill the holes they make means that it’s harder for bacteria to infiltrate, unlike with staples.

As a bonus, the developers of the bandage could infuse the needles with therapeutic compounds. “These substances may be, for example, antibiotics, growth-promoting compounds, or anti-inflammatory molecules,” says researcher Bohdan Pomahac, director of both Brigham and Women’s Hospital’s plastic surgery transplantation program and its burn center.

The researchers also want to make the bandage biodegradable. That way, “we can use inside the body to seal tissue like intestines,” Karp says.

Source: “A Better Bandage? Spiny Worm Inspires Stronger Adhesive,” TechNewsDaily, 4/16/13
Image by public domain.

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