Every year, more than 540 billion pounds of plastic are produced worldwide. Much of it ends up in the worldâ??s oceans, a fact that troubles MIT biology professor Anthony Sinskey.
â??Plastic does not degrade in the ocean. It just gets ground up into tiny particles,â?? he says. In the Pacific Ocean, a vast swath twice the size of Texas teems with tiny bits of oil-based plastic that can poison ocean life.
Sinskey canâ??t do much about the plastic thatâ??s already polluting the Earthâ??s oceans, but he is trying to help keep the problem from getting worse. Next month, a company he founded with his former postdoc, Oliver Peoples, will open a new factory that uses MIT-patented technology to build plastic from corn. The plant aims to produce annually 110 million pounds of the new bioplastic, which biodegrades in soil or the ocean.
Thatâ??s a fraction of one percent of the United Statesâ?? overall plastic production, which totaled 101.5 billion pounds in 2008. Though it will take bioplastics a long time before they can start making a dent in that figure, the industry has significant growth potential, says Melissa Hockstad, vice president for science, technology and regulatory affairs for SPI: The Plastics Industry Trade Association.
â??Bioplastics are making inroads into new markets and are an important area to watch for the future of the plastics industry,â?? says Hockstad, who noted that the current global market for biodegradable polymers is estimated at about 570 million pounds per year but is expected to more than double by 2012.
â??Timing is everythingâ??
For Sinskey and Peoples, the road started 25 years ago. Peoples, who had just earned his PhD in molecular biology from the University of Aberdeen, arrived in Sinskeyâ??s lab in 1984 and set out to sequence a bacterial gene. Today, high-speed sequencing machines could do the job in about a week. Back then, it took three years.
That gene, from the bacterium R. eutropha, turned out to code for an enzyme that allows bacteria to produce polyhydroxyalkanoate (PHA) â?? a naturally occurring form of polyester â?? starting with only sunlight, water, and a carbon source. (Bacteria normally manufacture PHA as a way to store carbon and energy.)
Sinskey and Peoples realized that if they could ramp up the bacteriaâ??s plastic producing abilities, they could harness the organisms for industrial use. In 1994, they started a company called Metabolix and took out exclusive patents from MIT on the gene work they had done on PHA-synthesizing bacteria.
Thus began a 15-year effort to develop the technology into a robust, large-scale process, and to win support for such an approach.
On the scientific side, Peoples and the scientists at Metabolix developed a method to incorporate several genes from different bacteria into a strain of E. coli. Using this process, now called metabolic engineering, they eventually created a strain that produces PHA at levels several-fold higher than naturally occurring bacteria.
However, they had some difficulty generating support (and funding) for the idea. In the early 1990s, the public was not very receptive to the idea of alternative plastics. â??Oil was $20 a barrel, and people didnâ??t believe in global warming,â?? Peoples recalls.
â??Timing is everything,â?? says Sinskey. â??There has to be a market for these materialsâ?? for them to be successful.
â??Growing interestâ??
The scientists believe that consumers are now ready for bioplastics. Such plastics have been commercially available for about a decade, mostly in the form of plastic cups, bottles and food packaging. Most of those products are made from a type of plastic called polylactic acid (PLA), which is also produced from corn. PLA is similar to PHA, but PHA has higher heat resistance, according to Peoples.
Possible uses for the Metabolix bioplastics include packaging, agricultural film, compost bags, business equipment and consumer products such as personal care products, gift cards and pens. Products like these, along with existing bioplastic products, tap into a â??growing interest in materials that can be made from renewable resources or disposed of through practices such as composting,â?? says Hockstad.
The new Metabolix plant, located in Clinton, Iowa, is a joint venture with Archer Daniels Midland. Metabolix is also working to engineer crops â?? including switchgrass â?? that will grow the plastic directly within the plant.
Turning to those agricultural starting materials could help reduce the amount of petroleum needed to manufacture traditional plastics, which currently requires about 2 million barrels of oil per day (10 percent of total U.S. daily oil consumption). â??Itâ??s important to develop alternative ways to make these chemicals,â?? says Peoples.
About five years ago, Professor Janet Sawicki at the Lankenau Institute in Pennsylvania read an article about nanoparticles developed by MITâ??s Daniel Anderson and Robert Langer for gene therapy, the insertion of genes into living cells for the treatment of disease. Sawicki was working on treating ovarian cancer by delivering â?? through viruses â?? the gene for the diphtheria toxin, which kills tumor cells.
â??I had been working with adenoviruses to deliver DNA, and I was running into some problems with using them,â?? says Sawicki. â??The problem with viruses is that they can produce a serious immune response in the host, which can be lethal.â??
After reading about the nanoparticles, Sawicki contacted Anderson and Langer, an MIT Institute Professor and chemical engineer, to inquire about launching a gene therapy project with the nanoparticles. â??I thought they would be perfect for what I was trying to do,â?? she recalls. The resulting collaboration has led to a promising potential treatment for ovarian cancer, one of the deadliest forms of cancer. This summer, the two laboratories reported that the nanoparticle-delivered gene therapy successfully suppressed ovarian tumor growth in mice.
The nanoparticles, made of biodegradable polymers, offer a chance to overcome one of the biggest obstacles to realizing the promise of gene therapy: The viruses often used to carry genes into the body can endanger patients. Furthermore, the particles created at MIT now rival virusesâ?? efficiency at delivering their DNA payload.
More tests are needed to confirm the particlesâ?? safety in humans, but because they are synthetic, there is less chance that they will provoke a harmful immune response, says Anderson, a biomedical engineer at the David H. Koch Institute for Integrative Cancer Research.
An artificial virus
There are nearly 1,000 clinical trials under way in the United States involving gene therapy, for diseases including cancer, cardiovascular disease and neurological disorders. However, no gene therapy treatments have been approved in the United States.
Viruses, the most commonly used gene-delivery vehicle, are a logical choice, since viruses are built to inject their own genetic material into host cells. However, serious clinical side effects, including the 1999 death of a high school student enrolled in a gene therapy trial at the University of Pennsylvania, have motivated some researchers to develop fully synthetic non-viral carriers.
Anderson started the nanoparticle project in Langerâ??s lab about 10 years ago, shortly after finishing his PhD in bacterial DNA repair. Though Anderson found his thesis topic â??scientifically interesting, it didnâ??t have a sense of immediate impact for me. I wanted to see if I could get closer to medicine.â??
Anderson and chemist David Lynn, then a postdoctoral fellow in Langerâ??s lab and now a professor at the University of Wisconsin, developed a large collection of different biodegradable polymers (large molecules composed of repeating subunits) known as poly(beta-amino esters).
When these synthetic polymers are mixed with DNA, they spontaneously assemble to form nanoparticles. These nanoparticles can travel through the body to the target cells, where they are taken up by a process known as endocytosis, the equivalent of cellular eating. Once â??eatenâ?? by the cells, the nanoparticles release their DNA payload inside of the cell, where it can then be activated by the cellular machinery. In some ways, these polymer-DNA nanoparticles can act like an artificial virus, delivering functional DNA when injected into or near the targeted tissue.
There are infinite possible sequences for such polymers, and small variations can make a polymer more or less efficient at delivering DNA. Anderson and Langer's group have developed a way to automate both the production of vast numbers of particles with slight variations and the screening techniques used to determine the particlesâ?? effectiveness.
â??Instead of trying to make one perfect polymer, we make thousands,â?? says Anderson. That increases the odds that the researchers will hit on a nanoparticle that does what they want.
â??If you can try one or two things every six months, it might take a while to find something that works. But if you can try tens of thousands of things, your chances of success are much greater, and thatâ??s true for any venue,â?? says Langer.
Improving efficiency
One drawback to non-viral vectors is that they are not as efficient as viruses at integrating their DNA payload into the target cellâ??s genome, says Leaf Huang, professor in the School of Pharmacy at the University of North Carolina. However, in the past several years, advances by Anderson and others have improved that efficiency by several orders of magnitude.
â??Non-viral vectors are now comparable to viral vectors, in some cases,â?? says Huang, whose research focuses on delivering genes surrounded by a fatty membrane. â??They have come a long way compared to 10 years ago.â??
Both viral and non-viral methods could eventually prove useful and safe, says gene therapy researcher Katherine High, who is part of a team that recently used viral gene therapy to restore some sight to children suffering from a congenital retinal disease.
â??Itâ??s been a slow road,â?? says High, a professor at the University of Pennsylvania Medical School, but over the past 20 years scientists have made much progress in managing the safety issues posed by viral vectors.
The ovarian cancer treatment developed at MIT and the Lankenau Institute has been successful in animal studies but is not yet ready for clinical trials. Such trials could get under way in a year or two, says Anderson, where their performance would be studied for several years. Meanwhile, the MIT researchers are exploring other uses for their nanoparticles. Last month, they reported using the particles to boost stem cellsâ?? ability to regenerate vascular tissue (such as blood vessels) by equipping them with genes that produce extra growth factors.
â??Weâ??ve had success with gene delivery using these nanoparticles, so we thought they might be a safer, temporary way to modify stem cells,â?? says Anderson.
During a tour of MIT labs prior to his talk at Kresge Auditorium last Friday, President Barack Obama saw demonstrations of several clean-energy technologies being developed at MIT: batteries that can be self-assembled by genetically engineered viruses; long-lasting high-efficiency light bulbs; windows that can double as solar energy collectors; and structures that could provide offshore windmills with built-in power storage.
The tour marked the first time a sitting president has visited MIT's laboratories to see demonstrations of ongoing research work and meet with faculty members who are conducting that research. He was escorted through the labs by MIT President Susan Hockfield and MIT Energy Initiative Director Ernest J. Moniz, and joined by Massachusetts Gov. Deval Patrick and U.S. Sen. John Kerry. The five faculty members who made the presentations to the President, along with some of their students, gathered in two labs in Building 13, with posters describing their work and demonstrations to show the technology in action.
Philip Guidice, commissioner of the Massachusetts Department of Energy Resources, was on campus Friday for the Presidential visit and said Obama was looking for examples of leading energy technologies of the future.
"Massachusetts is at the forefront, and MIT is very much a part of that," he said.
'A little nervous'
Marc Baldo, the Esther and Harold E. Edgerton Associate Professor of Electrical Engineering, demonstrated technology for concentrating solar energy systems using coated glass. Baldo said Obama was curious and asked a few questions about the research.
"It seemed like he had a really good time, that he actually found the whole experience quite stimulating," Baldo said "I was a little nervous, but I got the impression that he's used to walking into rooms full of nervous people, and he just put everyone at ease."
Paula Hammond, along with research collaborator Angela Belcher, demonstrated work on using genetically engineered viruses to produce self-assembling solar cells and batteries.
"He was very responsive, and an incredibly warm person," Hammond SB '84, PhD '93, the Bayer Professor of Chemical Engineering, said of Obama. "When we described the self-assembly process, he asked several very intelligent questions, about the scalability of the process and so on."
In fact, after he heard part of the description of plans to develop the system so that batteries or solar cells could be made by spraying alternating layers of different organisms onto a glass surface, Hammond said, Obama turned to reporters who accompanied him on the tour and said "did you understand that?" - and then proceeded to explain the information in his own words.
"He was exactly correct," Belcher said. "I asked him if he wanted to teach my class." When Belcher, the Germehausen Professor of Materials Science and Engineering and Biological Engineering, explained that her biologically based system made it possible to conduct a billion experiments at a time, he interrupted to say, "Really?" Belcher said "Yes we can," to which he quipped, "That was my slogan, you know." Overall, he was "serious, but kind of joking at the same time," Belcher said.
"His demeanor was very inquisitive and playful," said Vladimir Bulovic, the KDD Associate Professor of Communications and Technology, who demonstrated high-efficiency, long-lasting light bulbs based on quantum dot technology. When Bulovic showed him some of the equipment used to manufacture the lights, including a vacuum chamber that produces a harder vacuum than would be found in space between the Earth and the moon, Obama asked him, "When one of these pieces of equipment breaks, who do you call?" Bulovic explained that the equipment is all custom built at MIT, and he and his colleagues and students are the "glorified car mechanics" who have to fix anything that breaks.
"I believe that president knew what my answer would be and that he wanted to give me a chance to vocalize the resourcefulness of MIT engineers in front of the national press," Bulovic added.
A presidential seal of approval
Before the president left the lab, Bulovic, at the request of some of his students, asked if the President would be willing to "memorialize the moment." He was standing next to a control panel for some equipment that many of the students use almost daily. "He graciously did sign it," he said, "and added 'Great work!' up at the top." Since he had already seen all of the other presentations at that point, Bulovic said he and his students interpreted that "as a message to all of us, that he was impressed by all the work he saw. It was a message to the entire MIT community."
As the President mentioned in his speech at Kresge, during his lab visit Belcher handed him a wallet-size card displaying the periodic table of the elements - something she routinely gives to students and visitors. As soon as he was given the card, he placed it in his pocket and deadpanned: "I'll glance at it periodically."
Alex Slocum, the Neil and Jane Pappalardo Professor of Mechanical Engineering, demonstrated his plan for offshore wind turbines with a built-in energy storage system using pumped water. Slocum said that "it's clear that he really listens; his eyes are constantly in motion taking in information. He asked some really good questions, and he was very warm and friendly, with a good sense of humor."
Slocum added that it was clear from the interaction that "he really wants to learn; he genuinely cares. He wants to know what can be done, and what is being done. It was really refreshing."
Bulovic was impressed with Obama's "eagerness to absorb more information on what science can do for us." The whole experience, he said, was "overwhelming and humbling."
Popular Science magazine has named MIT associate professor Michael Strano and Whitehead Fellow Kate Rubins to its annual "Brilliant 10" list of top young scientists.
Strano, 33, the Charles and Hilda Roddey Associate Professor of Chemical Engineering, was honored for his work with confined quantum materials (such as graphene). His work "has the power to transform cancer medicine, solar power, electronics and more," according to the magazine.
Rubins, 31, a fellow at the Whitehead Institute, recently pioneered a new, superfast method of isolating and sequencing the genetic material of the monkeypox virus, and is now training at NASA to become an astronaut on the shuttle's successor craft, Orion.
The Franklin Institute has selected JoAnne Stubbe, the Novartis Professor of Chemistry and professor of biology, and Shafrira Goldwasser, the RSA Professor of Computer Science and Electrical Engineering, as winners of Benjamin Franklin Medals.
Stubbe, who recently won the National Medal of Science, will receive the Benjamin Franklin Medal in Chemistry. According to the award citation, she is being honored "for uncovering the intricate processes by which cells safely use free radicals, for developing new cancer treatments, and for improving the production of environmentally friendly biodegradable polymers."
Goldwasser will receive the Benjamin Franklin Medal in Computer and Cognitive Science "for her fundamental contributions to the theoretical foundation of modern cryptography, which led to techniques that can guarantee secure access to the Internet."
Stubbe and Goldwasser are among 11 laureates selected this year. They will receive their awards on April 29, 2010, at the Franklin Institute in Philadelphia.
In April 2009, the Deshpande Center issued its annual Institute-wide call for proposals for two levels of grant awards â?? Ignition and Innovation. The grants target projects focusing on novel, enabling and potentially useful ideas and innovations in all areas of technology. Funding for Ignition awards â?? up to $50,000 per grant â?? might enable only exploratory experiments and limited proof of concept, and an Ignition Grant can position projects to receive further funding to continue to develop an innovation. Funding for Innovation awards â?? for as much as $250,000 per grant â?? is meant to benefit projects that have progressed beyond their earliest stages and are closer to commercialization. After a rigorous three-month process of collection, evaluation, presentation and selection, all under the guidance of the center's executive director, Leon Sandler, and its faculty director, Professor Charles Cooney, the final award decisions were made in August 2009 and announced publicly on Wednesday, Oct. 7, 2009. The center is pleased to announce the following fall 2009 grantees:
New Antibiotic Target: Graham Walker A project to attempt to isolate lead compounds to develop a new antibiotic. (Renewal from fall 2008 grant round.)
For more details on the research projects, visit: http://web.mit.edu/deshpandecenter/release_100709.html About the MIT Deshpande Center for Technological Innovation The Deshpande Center is part of the MIT School of Engineering and was established through an initial $20 million gift from Jaishree Deshpande and Desh Deshpande, the co-founder and chairman of Sycamore Networks. It is supported by gifts from alumni, friends and sponsors. The center serves as a catalyst for innovation and entrepreneurship by supporting leading-edge research and bridging the gap between the laboratory and marketplace. Additional information on the Deshpande Center's grant program, research portfolio and other entrepreneurial resources can be found at http://web.mit.edu/deshpandecenter/
In the summer of 2008, Tamara Litwin embarked on a three-month internship in Israel with Ada Yonath, who was awarded the Nobel Prize in Chemistry last week. The award recognizes Professor Yonath's research on protein "factories" in cells.
Organized by the MIT-Israel Program, Litwin's internship project at the Weizmann Institute involved X-ray crystallography of antibiotic-resistant ribosomes. "I had a fantastic experience in Israel this summer, doing world-class science and experiencing a different culture at the same time," she says.
MIT-Israel is one of 10 country programs in the MIT International Science and Technology Initiatives, or MISTI. MISTI matches more than 400 MIT students each year with paid professional internships and research projects around the world, and awards funding to MIT faculty for international projects and collaboration.
Fuel cells, devices that can produce electricity from hydrogen or other fuels without burning them, are considered a promising new way of powering everything from homes and cars to portable devices like cellphones and laptop computers. Their big advantage â?? the prospect of eliminating emissions of greenhouse gases and other pollutants â?? has been outweighed by their very high cost, and researchers have been trying to find ways to make the devices less expensive.
Now, an MIT team led by Associate Professor of Mechanical Engineering and Materials Science and Engineering Yang Shao-Horn has found a method that promises to dramatically increase the efficiency of the electrodes in one type of fuel cell, which uses methanol instead of hydrogen as its fuel and is considered promising as a replacement for batteries in portable electronic devices. Since these electrodes are made of platinum, increasing their efficiency means that much less of the expensive metal is needed to produce a given amount of power.
The key to the boost in efficiency, the team found, was to change the surface texture of the material. Instead of leaving it smooth, the researchers gave it tiny stairsteps. This approximately doubled the electrode's ability to catalyze oxidation of the fuel and thus produce electric current. The researchers believe that further development of these surface structures could end up producing far greater increases, yielding more electric current for a given amount of platinum.
Their results are reported Oct. 13 in the Journal of the American Chemical Society. The paper's eight authors include chemical engineering graduate student Seung Woo Lee and mechanical engineering postdoctoral researcher Shuo Chen, along with Shao-Horn and other researchers at MIT, the Japan Institute of Science and Technology, and Brookhaven National Laboratory.
"One of our research focuses is to develop active and stable catalysts," Shao-Horn says, and this new work is a significant step toward "figuring out how the surface atomic structure can enhance the activity of the catalyst" in direct methanol fuel cells.
Resolving a controversy
In their experiments, the team used platinum nanoparticles deposited on the surface of multi-wall carbon nanotubes. Lee says that many people have been experimenting with the use of platinum nanoparticles for fuel cells, but the results of the particle size effect on the activity so far have been contradictory and controversial. "Some people see the activity increase, some people see a decrease" in activity as the particle size decreases. "There has been a controversy about how size affects activity."
The new work shows that the key factor is not the size of the particles, but the details of their surface structure. "We show the details of surface steps presented on nanoparticles and relate the amount of surface steps to the activity," Chen says. By producing a surface with multiple steps on it, the team doubled the activity of the electrode, and the team members are now working on creating surfaces with even more steps to try to increase the activity further. Theoretically, they say, it should be possible to enhance the activity by orders of magnitude.
Shao-Horn suggests that the key factor is the addition of the edges of the steps, which seem to provide a site where it's easier for atoms to form new bonds. The addition of steps creates more of those active sites. In addition, the team has shown that the step structures are stable enough to be maintained over hundreds of cycles. That stability is key to being able to develop practical and effective direct methanol fuel cells.
Team members also hope to understand whether the steps enhance the other part of the process that takes place in a fuel cell. This study looked at the enhancement of oxidation, but the other side of a fuel cell undergoes oxygen reduction. Does the addition of steps to the surface also enhance the oxygen reduction? "We need to find why it does, or why it doesn't," Shao-Horn says. The researchers expect to have answers to that question in the next few months.
President Barack Obama today presented MIT biochemist JoAnne Stubbe with the National Medal of Science during a White House ceremony.
Stubbe received the nation's highest science honor for her work in understanding the mechanisms of enzymes that play an essential role in DNA replication and repair. The research has had significant impacts on fields ranging from cancer drug development to synthesis of biodegradable plastics.
Stubbe was among nine researchers selected to receive the award this year, and Obama thanked the group for their contributions to fields as diverse as medicine, energy, computing, genetics and neuroscience. "They have fostered innovation that has saved millions of lives and improved the lives of countless others," he said. "This nation owes all of them a debt of gratitude far greater than any medal can bestow."
After returning from Washington, Stubbe said that the East Room ceremony was an emotional experience. Before the ceremony, the medal recipients took a tour of the White House, and Stubbe noted that "the whole atmosphere in the White House, with all the young people he has working there, was so upbeat."
Stubbe's studies of ribonucleotide reductases (RNRs), which play a key role in DNA copy and repair, have led to the design of a drug, gemcitabine, which is now used to treat pancreatic and other cancers. She also discovered the structure and function of bleomycin, an antibiotic used as a cancer drug.
Before beginning his official remarks, Obama joked that he had an ulterior motive in inviting the distinguished group of scientists to the White House. "Sasha has a science fair coming up," he noted. "I was thinking you guys could give us a few tips. Michelle and I are a little rusty on our science."
Stubbe, who joined the MIT faculty in 1987, is the Novartis Professor of Chemistry and a professor of biology. She is a member of the National Academy of Sciences, the American Academy of Arts and Sciences and the American Philosophical Society.
In addition to Stubbe, this year's winners include MIT alumnus Rudolf Kalman of the Swiss Federal Institute of Technology in Zurich. Kalman earned his bachelor's and master's degrees in electrical engineering and computer science from MIT in 1953 and 1954, respectively.
MIT biochemist JoAnne Stubbe will receive a National Medal of
Science â?? the nation's top science honor â?? for her work in
understanding the mechanisms of enzymes that play an essential role in
DNA replication and repair, President Barack Obama announced Thursday.
Obama will present the award to Stubbe and eight other scientists during an Oct. 7 White House ceremony.
"Professor
JoAnne Stubbe is a scientist's scientist: fiercely intelligent,
doggedly curious and unbending in her pursuit of truth," said MIT
President Susan Hockfield. "We are extraordinarily proud that she has
received the National Medal of Science for her pioneering work in
advancing our understanding of the chemistry at the root of life."
Stubbe,
who learned about the award in a late Tuesday night phone call from
John Holdren '65, SM '66, Obama's science and technology adviser, said
she is excited to make the trip to the White House and meet the
president.
"It's a little overwhelming, and a great honor," said
Stubbe, the Novartis Professor of Chemistry and a professor of biology.
"For the first time, everybody in my family is excited about what I
do," she joked.
According to the award citation, Stubbe was
honored "for her groundbreaking experiments establishing the mechanisms
of ribonucleotide reductases, polyester synthases, and natural product
DNA cleavers â?? compelling demonstrations of the power of chemical
investigations to solve problems in biology."
"These scientists,
engineers and inventors are national icons, embodying the very best of
American ingenuity and inspiring a new generation of thinkers and
innovators," Obama said in the announcement. "Their extraordinary
achievements strengthen our nation every day-not just intellectually
and technologically but also economically, by helping create new
industries and opportunities that others before them could never have
imagined."
Stubbe's
work over the past four decades has had profound impacts on fields
ranging from cancer drug development to synthesis of biodegradable
plastics.
One of her major accomplishments is unraveling the mechanism of
ribonucleotide reductases (RNRs), which play a key role in converting
nucleotides to deoxynucleotides â?? thereby allowing DNA to be copied and
repaired. Her studies in this area have led to the design of a drug,
gemcitabine, which is now used to treat pancreatic and other cancers.
MIT chemistry professor Stephen Lippard, who won the National Medal of
Science in 2004, describes Stubbe as "one of the top few mechanistic
biochemists of her generation." Stubbe spent a sabbatical in Lippard's
lab in 1983 before joining the MIT faculty, and he has long admired her
dedication, critical thinking, and relentless pursuit of the truth.
"There are few people with her drive for understanding and insistence
on accuracy in experimental work," he says. "It is a pleasure to be her
colleague."
Stubbe also discovered the structure and function of bleomycin, an
antibiotic used as a cancer drug. Her research team, in collaboration
with the laboratory of John Kozarich at ActivX, revealed how bleomycin
damages DNA, killing the cancer cell. They also identified the
structure of the DNA damage.
Stubbe is now working with MIT Biology Professor Anthony Sinskey to use
bacterial enzymes to produce biodegradable thermoplastics, which could
be a potential alternative to traditional oil-based plastics. They were
the first to isolate one of the enzymes, known as PHA synthases, and to
define how the plastic polymers form.
The National
Medal of Science was created in 1959 and is administered for the White
House by the National Science Foundation. Awarded annually, the medal
recognizes individuals who have made outstanding contributions to
science and engineering. Nominees are selected by a committee of
presidential appointees based on their advanced knowledge in, and
contributions to, the biological, behavioral/social, and physical
sciences, as well as chemistry, engineering, computing, and mathematics.
Stubbe
is a member of the National Academy of Sciences, the American Academy
of Arts and Sciences and the American Philosophical Society. She has
won the National Academy of Sciences Award in Chemical Sciences (2008),
the Kaiser Award (2008), the Nakanishi Award (2009), the Alfred Bader
Award in Bioorganic and Bioinorganic Chemistry (1997), the Repligan
Award (2004), the Pfizer Award in Enzyme Chemistry (1986), the
ICI-Stuart Pharmaceutical Award for Excellence in Chemistry (1989), the
Cope Scholar Award (1993), the Richards Medal from the Northeastern
Section of the American Chemical Society (1996) and the Prelog Medal
(2009), among others.
She earned a bachelor's degree in
chemistry in 1968 from the University of Pennsylvania and a PhD in
organic chemistry in 1971 from the University of California at Berkeley.
Stubbe
joined the MIT faculty in 1987 from the University of Wisconsin at
Madison, where she had been a faculty member since 1983. She has also
taught at the Yale University School of Medicine (1977-80) and at
Williams College (1972-77) and was an NIH postdoctoral fellow at
Brandeis (1975-77) and a postdoctoral researcher at the University of
California (1971-72).
Other current MIT faculty who have won the
National Medal of Science include Ann Graybiel (2001), Robert Langer
(2006), Stephen Lippard (2004), Alexander Rich (1995), Phillip Sharp
(2004), Isadore Singer (1983) and Robert Weinberg (1997). Emeritus
faculty who have won the award are David Baltimore (1999), Mildred
Dresselhaus (1990), Gobind Khorana (1987), Daniel Kleppner (2006), Paul
Samuelson (1996), Robert Solow (1999) and Kenneth Stevens (1999).
In
addition to Stubbe, this year's winners of the National Medal of
Science include MIT alumnus Rudolf Kalman of the Swiss Federal
Institute of Technology in Zurich. Kalman earned his bachelor's and
master's degrees in electrical engineering and computer science from
MIT in 1953 and 1954, respectively.
MIT retained its fourth-place position among national universities while the Institute's undergraduate engineering program continued its decades-long reign in U.S. News & World Report's annual rankings of America's best colleges and universities, which were released today.
In the overall university rankings, MIT shares the number four slot with three other schools - Caltech, Stanford and the University of Pennsylvania. Harvard and Princeton share the top spot this year, while Yale ranks third.
For more than 20 years, MIT has held the top spot in the magazine's overall undergraduate engineering rankings. Specialized engineering disciplines at MIT that U.S. News also ranked as the nation's best this year include aeronautics and astronautics, chemical, electrical and computer science, materials and mechanical. In materials science and engineering, MIT's ranking jumped from a tie for fourth last year to a first-place ranking this year.
MIT's undergraduate business program tied with the University of California, Berkeley, as the nation's second best. MIT took top honors for its undergraduate business specialties in production and operations management, management information systems, quantitative analysis, and supply chain management.
The U.S. News ranking formula gives greatest weight to the opinions of those in a position to judge a school's undergraduate academic excellence. The peer assessment survey allows presidents, provosts and deans of admissions to account for intangibles such as faculty dedication to teaching.
Ranked by its peer universities in this category, MIT shared top and equal standing with Harvard, Stanford and Princeton.
Among other key criteria for judging schools is selectivity as gauged by acceptance rate (MIT tied for second) and financial resources (MIT was ranked third).
The magazine rated MIT among the top 10 most racially diverse universities in America. The Institute also tied with Dartmouth College for fourth in the ranking of the nation's most economically diverse universities as determined by the percentage of students receiving Pell grants.
Finally, the report judged an MIT education to be a great value. MIT ranked fifth among national universities in a measure of price relative to quality; last year, the Institute ranked fourth.
A team of MIT chemists has devised a new way to add fluorine to a variety of compounds used in many drugs and agricultural chemicals, an advance that could offer more flexibility and potential cost-savings in designing new drugs.
Drug developers commonly add fluorine atoms to drugs, such as the cholesterol-lowering rosuvastatin, to keep the body from breaking them down too quickly. Many of these drugs contain aromatic rings - a type of six-carbon ring - and attaching a fluorine atom to the rings can be a difficult, expensive process.
"It's hard to add fluorine at a late stage, once you have a complete molecule already put together, because traditional methods can be quite harsh with respect to temperature or other factors," says Stephen L. Buchwald, the Camille Dreyfus Professor of Chemistry at MIT.
In their new technique, Buchwald and his colleagues used a palladium catalyst to attach a fluorine atom to aromatic compounds. The technique could be used in the design and testing of new drugs, or to create new imaging agents for positron emission tomography (PET) scanning.
Donald Watson, a former postdoctoral associate in Buchwald's lab, now an assistant professor of chemistry at the University of Delaware, is lead author of a paper describing the new synthesis in the Aug. 13 early online edition of Science.
During the new process, the palladium catalyst removes a group of atoms called a triflate attached to the aromatic compound, then replaces it with a fluorine atom taken from a simple salt, such as cesium fluoride. This marks the first time chemists have replaced a triflate attached to an aromatic ring with a fluorine atom in one catalytic reaction.
"Many people believed it would not be possible to do this," says Buchwald.
"While the method is probably not currently efficient enough to be used in manufacturing, we are working to speed up the reaction, increase its efficiency and make it more environmentally and user-friendly," says Buchwald. "We ultimately hope to make it general enough to be useful for manufacturing."
Carbon nanotubes - tiny, rolled-up tubes of graphite - promise to add speed to electronic circuits and strength to materials like carbon composites, used in airplanes and racecars. A major problem, however, is that the metals used to grow nanotubes react unfavorably with materials found in circuits and composites. But now, researchers at MIT have for the first time shown that nanotubes can grow without a metal catalyst. The researchers demonstrate that zirconium oxide, the same compound found in cubic zirconia "fake diamonds," can also grow nanotubes, but without the unwanted side effects of metal.
The implications of ditching metals in the production of carbon nanotubes are great. Historically, nanotubes have been grown with elements such as iron, gold and cobalt. But these can be toxic and cause problems in clean room environments. Moreover, the use of metals in nanotube synthesis makes it difficult to view the formation process using infrared spectroscopy, a challenge that has kept researchers in the dark about some of the aspects of nanotube growth.
"I think this fundamentally changes the discussion about how we understand carbon nanotubes synthesis," says Brian Wardle, professor of aeronautics and astronautics who led the study, published Aug. 10 in the online version of the Journal of the American Chemical Society.
Wardle adds that some researchers might find the result controversial since no one has ever proven that anything other than a metal can grow a nanotube. "People report new metals [as catalysts] every so often," he says. "But now we have a whole new class of catalyst and new mechanism to understand and debate."
The conventional model for nanotube growth goes like this: A substrate is sprinkled with nanoparticle seeds made of a certain metal, of the same diameter of the desired nanotubes. The substrate and nanoparticles are heated to 600 to 900 degrees Celsius, and then a carbon-containing gas such as methane or alcohol is added. At the high temperatures, molecules break apart and reassemble. Some of these carbon-containing molecules find their way to the surface of a nanoparticle where they dissolve and then precipitate out, in nanotube form.
The researchers found that if they just used zirconium oxide nanoparticles on the substrate, they could coax carbon into nanotubes as well. Importantly, the mechanism for growth seems to be completely different from that of metal nanoparticle-grown tubes. Instead of dissolving into the nanoparticle and precipating out, zirconia-grown nanotubes appear to assemble directly on the surface.
In collaboration with Professor Stephan Hofmann at the University of Cambridge in England, the MIT researchers took images of the oxide-based nanotubes using X-ray photoelectron spectroscopy during growth. This allowed them to see that when nanotubes formed, zirconium oxide persisted, and didn't form into a metal, bolstering their conclusions.
One of the most exciting implications of the finding is that it means that carbon fiber and composites, used to make different types of crafts, could be strengthened by nanotubes. "Composites are durable, but fail under certain loading conditions, like when plywood flakes and splinters apart," says Stephen Steiner, an MIT graduate student and the study's first author. "But what if you could reinforce composites at the microlevel with nanotubes the way that rebar reinforces concrete in a building or a bridge? That's what we're trying to do to improve the mechanical properties and resistance to fracturing of carbon composites."
Steiner says the reason that planes like Airbus' A380 and Boeing's new 787 are made of only 40 percent composites and not 90 percent is because composites aren't strong enough for all parts of the craft. But if they were bolstered by nanotubes, then the planes could be made of more composites, which would make them lighter, and less expensive to fly because they wouldn't need as much fuel.
The findings are already impressing researchers in industry. "This innovation has far-reaching implications for commercial productions of carbon nanotubes," says David Lashmore, CTO of Nanocomp Technologies Inc., a company in Concord, N.H., that was not involved in the research. "It for the first time allows the use of a ceramic catalyst instead of a magnetic transition metal, some of which are carcinogenic."
Wardle suspects that more oxide-based catalysts will be found in the coming years. He and his team will focus on trying to understand the fundamental mechanisms of this type of nanotube growth and help to contribute more types of catalysts to the nanotube-growing arsenal. While the researchers don't have a timeline, they suspect that it would be easy to commercialize the process as it's simple, adaptable and, in many ways, more flexible than growth with metal catalysts.
This work was supported by Airbus S.A.S., Boeing, Embraer, Lockheed Martin, Saab AB, Spirit AeroSystems, Textron Inc., Composite Systems Technology, and TohoTenax through MIT's Nano-Engineered Composite aerospace Structures (NECST) Consortium.
A new computer model developed at MIT can help solve a problem that has plagued drug companies trying to develop promising new treatments made of antibodies: Such drugs have a relatively short shelf life because they tend to clump together, rendering them ineffective.
Antibodies are the most rapidly growing class of human drugs, with the potential to treat cancer, arthritis and other chronic inflammatory and infectious diseases. About 200 such drugs are now in clinical trials, and a few are already on the market.
Patients can administer these drugs to themselves, but this requires high doses - and the drugs must therefore be stored at high concentrations. However, under these conditions the drugs tend to clump, or aggregate. Even if they are stored at lower concentrations and administered by a doctor intravenously, they often have stability issues. Addressing such issues typically takes place later in the drug development process, and the cost - both in time and money - is often high.
Currently there is no straightforward way to address these storage issues early in the development process.
"Drugs are usually developed with the criteria of how effective they'll be, and how well they'll bind to whatever target they're supposed to bind," says Bernhardt Trout, professor of chemical engineering and leader of the MIT team. "The problem is there are all of these issues down the line that were never taken into account."
Trout and his colleagues, including Bernhard Helk of Novartis, have developed a computer model that can help designers identify which parts of an antibody are most likely to attract other molecules, allowing them to alter the antibodies to prevent such clumping. The model, which the researchers aim to incorporate in the drug discovery process, is described in a paper appearing in the online edition of the Proceedings of the National Academy of Sciences the week of June 29.
Preventing aggregation
Most of the aggregation seen in antibodies is due to interactions between exposed hydrophobic (water-fearing) regions of the proteins.
Trout's new model, known as SAP (spatial aggregation propensity), offers a dynamic, three-dimensional simulation of antibody molecules. Unlike static representations such as those provided by X-ray crystallography, the new model can reveal hydrophobic regions and also indicates how much those regions are exposed when the molecule is in solution. The other important aspect of the model is that it selects out regions responsible for aggregation, as opposed to just single sites.
Once the hydrophobic regions are known, researchers can mutate the amino acids in those regions to decrease hydrophobicity and make the molecule more stable. Using the model, the team produced mutated antibodies with greatly enhanced stability (up to 50 percent more than the original antibodies), and the mutations had no adverse affect on their function.
Lead authors of the PNAS paper are Naresh Chennamsetty and Vladimir Voynov, postdoctoral associates in MIT's Department of Chemical Engineering. Other authors are chemical engineering postdoctoral associate Veysel Kayser and Bernhard Helk of Novartis.
The research was funded by Novartis Pharma AG and computer time was provided in part by the National Center for Supercomputing Applications.
Scientists from disparate fields of medical research, physical sciences and engineering gathered June 12 at MIT to discuss how to harness computational immunology to develop treatments for some of today's deadliest infectious diseases, including HIV/AIDS.
The Symposium on Computational Immunology was hosted by the Ragon Institute, established in February to find new ways to prevent and cure human disease by capturing the power of the immune system.
The purpose of the first major symposium hosted by the Ragon Institute reflected that of the institute as a whole: to bring together diverse disciplines, people, ideas and approaches to confront and overcome basic and applied challenges hindering the development of a vaccine against, as Professor Arup Chakraborty puts it, "scourges on the planet."
"In recent years, theoretical and computational approaches rooted in the physical and engineering sciences have ... shed light on basic questions in molecular and cellular immunology and host-pathogen dynamics," said Chakraborty, the Robert T. Haslam Professor of Chemical Engineering, Chemistry, and Biological Engineering and Ragon Institute team leader.
"[Our intention] was to make such synergistic theoretical and experimental research activities more vigorous by bringing together physical scientists, engineers, virologists and immunologists to think about the basic science that must be understood and harnessed for designing vaccination strategies against HIV and other infectious agents."
The institute is taking steps toward vaccine development, including development of a humanized mouse model to predict vaccine-induced immune responses in humans, determination of the effector function of immune cells at the single cell level, and multidisciplinary studies of individuals who control HIV without medication, as well as those with acute HIV infection.
Dr. Bruce Walker, an MGH physician-investigator and director of the Ragon Institute, believes another important step for the institute is to involve more MIT researchers, and to create a cadre of scientists committed to solving the AIDS problem at the cellular level.
"To prevent viruses from getting into cells or prevent progeny viruses from being produced, you can think about the various arms of the immune response: the innate immune response, the adaptive immune response involving antigen presenting cells, B cells making neutralizing antibodies, cytotoxic T cells, T helper cells. Part of the problem in the field has been that, until recently, these have been studied in 'silos,'" Walker said during his presentation, "Challenges and Opportunities in HIV Research." "There's been very little integration across these different aspects of the immune response in terms of trying to understand what's really going on."
Speakers from MIT, Stanford University, Los Alamos National Laboratory and Harvard University participated in the day-long meeting, which was broken into three major areas: basic immunology, the evolution of pathogens and antibodies, and HIV dynamics and vaccine design.
Bose Award for Excellence in Teaching--Given to a faculty member whose contributions have been characterized by dedication, care and creativity - Vladimir Bulovic, associate professor of electrical engineering and computer science
Junior Bose Award--For an outstanding contributor to education from among the junior faculty of the School of Engineering - Krystyn J. Van Vliet, assistant professor of materials science and engineering
Ruth and Joel Spira Awards for Excellence in Teaching--Awarded to one faculty member each in electrical engineering and computer science, mechanical engineering, and nuclear science and engineering to acknowledge "the tradition of high quality engineering education at MIT." A fourth award will rotate among the school's five other academic departments, beginning with Aeronautics and Astronautics in 2009 - Elfar Adalsteinsson, associate professor of EECS & HST - Daniel Frey, associate professor of mechanical engineering and Engineering Systems Division - Dennis G. Whyte, associate professor of nuclear science and engineering - Zoltan S. Spakovszky, associate professor of aeronautics and astronautics
School of Engineering Graduate Student Award for Extraordinary Teaching and Mentoring--Established in 2006 to recognize an engineering graduate student who has demonstrated extraordinary teaching and mentoring as a teaching or research assistant - Gunaranjan Chaudhry G, mechanical engineering
Capers and Marion McDonald Award for Excellence in Mentoring and Advising--To a faculty member who has demonstrated a lasting commitment to personal and professional development - Leslie A. Kolodziejski, professor of electrical engineering and computer science
The Barry M. Goldwater Scholarship--Given to students who exhibit an outstanding potential and intend to pursue careers in mathematics, the natural sciences, or those engineering disciplines that contribute significantly to the technological advances of the United States - Alvin S. Chen '10, Irvine, Calif. - Vidya Ganapati '10, Portland, Ore.
The Henry Ford II Award--Presented to a senior engineering student who has maintained a cumulative average of 5.0 at the end of their seventh term and who has exceptional potential for leadership in the profession of engineering and in society - Alona Birjiniuk '09, Weston, Mass.
Alpha Chi Sigma--For distinguished scholastic achievement, originality and breadth of interest in chemistry - Annelise R. Beck '09, Minnetrista, Minn. - Stephen D. Fried '09, Leawood, Kan. - Veena Venkatachalam '09, Berkeley Heights, N.J.
Chemistry Research Award--For outstanding contributions in the area of research - Koyel Bhattacharyya '09, Rockville, Md. - Shanying Cui, San Diego, Calif. - Kyrstin L. Fornace '09, Bethesda, Md. - Christopher J. Love '09, Atlantis, Fla. - Thomas F. Martinez '09, Sunland, Calif. - Sarah J. Smith '09, Whitesboro, N.Y. - Yunji Wu '09, Iowa City, Iowa
Research & Teaching Award--For outstanding contributions in the areas of research and teaching to the department - Sarah Campbell Proehl '09, Pleasantville, N.Y.
Merck Index Awards--For outstanding scholarship - Tamara R. Litwin, Round Rock, Texas - Elise G. Liu '09, Auburn, Ala. - WenHui Tan '09, Henderson, Nev. - Alexandra P. Tcaciuc '09, Bucharest, Romania
Hypercube Scholar Award--In recognition of outstanding contributions in the advancement of computational chemistry - Jongjin B. Kim '09, Pittsburgh, Pa.
ACS Analytical Chemistry Award--For achievement by a junior in analytical chemistry - Sidney E. Creutz '10, Earlysville, Va.
Sophomore Achievement Award--For outstanding performance as a sophomore in academics, research and service to the department - Jonathon T. Gunn '11, - St. Charles, Mo.
CRC Press Freshman Chemistry Achievement Award--For outstanding academic achievement in chemistry - Daniel S. Levine '12, Succasunna, N.J.
Strem Award--In recognition of the best undergraduate research presentation - Annelise R. Beck '09, Minnetrista, Minn.
Association of MIT Alumnae Senior Academic Award Winner - Annelise R. Beck '09, Minnetrista, Minn.
Barry M. Goldwater Scholarship--Outstanding undergraduate college student pursuing a career in the fields of science, math or engineering - Sidney E. Creutz '10, Earlysville, Va.
Earll M. Murman Award--For excellence in Undergraduate Advising - Professor Robert W. Field
Frederick D. Greene Teaching Award - Paul D. Boudreau '09, Cambridge, Mass.
Merck Fellow - Michael Blaisse '09, Harrisburg, Pa.
Cunningham Scholar Fellow - Shenwen Huang '10, Mayfield Heights, Ohio
William L. Stewart Jr. Award--Recognizes outstanding contributions to extracurricular activities and events during the year - Johnathan Cromwell '09, Santa Clarita, Calif.
Genetech Scholar Award - Timothy Humpton '10, Jamison, Pa.
The Robert T. Haslam Cup--The Robert T. Haslam Cup is awarded each year to a student who shows outstanding professional promise in Chemical Engineering - Jacqueline Douglass '09, Memphis, Tenn.
The Roger De Friez Hunneman Prize--For recognition of outstanding scholarship in class and research -Jason Whittaker '09, Wayland, Mass.
The Chemical Engineering Department Special Service Awards - Kathryn Schumacher '09, Frederick, Md. - Adekunle Adeyemo G, Ogudu Ojota, Lagos, Nigeria - Joshua Allen G, White Bear Lake, Minn. - Emily Chang G, Edison, N.J. - Himanshu Dhamankar G, Mumbai, India - Jyoti Goda G, Rourkela, India - Patrick Heider G, Greenfield, Mass. - Jaisree Iyer G, Mumbai, Maharashtra, India - Becky Ladewski G, Lawrence, Mass. - Bradley Niesner G, Buda, Texas - Michael Petr G, Wichita, Kan. - Justin Quon G, Hockessin, Del. - Yuxi Zhang G, Nanjing, Jiangsu, China
Edward W. Merrill Outstanding Teaching Assistant Award - Jamila Saifee G, Tarzana, Calif.
A pair of major grants from the U.S. Department of Defense will support MIT research on building ultra-fast microchips for computation and communications, as well as research on new electronic surveillance systems.
The grants, given out under a program called the Multidisciplinary University Research Initiative, were among 41 awarded nationwide with a total value of $260 million.
Five MIT researchers, led by Principal Investigator Michael Strano, the Charles and Hilda Roddey Associate Professor of Chemical Engineering, along with colleagues at Harvard and Boston University, received a $5 million, five-year grant from the Office of Naval Research (ONR) for work on building a new generation of ultra-fast (terahertz) microchips from graphene, a form of carbon. Co-directors of the project are Assistant Professor of Physics Pablo Jarillo-Herrero, on the physics side, and Assistant Professor of Electrical Engineering Tomas Palacios on the engineering side. The project also includes Assistant Professor of Electrical Engineering Jing Kong, and Institute Professor Mildred Dresselhaus, as well as physicists Charles Marcus and Amir Yacoby of Harvard and physicist Antonio Castro Neto of BU. This grant, says Palacios, will make MIT and its collaborators "one of the strongest multidisciplinary teams working on graphene in the world."
The other MIT team to receive a grant, also from ONR, is headed by Daniela Rus, professor of computer science and engineering and associate director of the Computer Science and Artificial Intelligence Laboratory. Rus' team, which also includes researchers from Boston University, University of California, Berkeley, and University of Pennsylvania, will focus on a project called Smart Adaptive Reliable Teams for Persistent Surveillance (SMARTS).
In addition to the two major, MIT-led teams receiving grants, seven other DoD grants went to teams that also include MIT researchers.
In his office, MIT Professor of Chemical Engineering Gregory Rutledge keeps a small piece of fabric that at first glance resembles a Kleenex. This tissue-like material, softer than silk, is composed of fibers that are a thousand times thinner than a human hair and holds promise for a wide range of applications including protective clothing, drug delivery and tissue engineering.
Such materials are produced by electrospinning, a technique that has taken off in the past 10 years, though the original technology was patented more than a century ago. In Rutledge's lab, researchers are exploring new ways to create electrospun fibers, often incorporating materials that add novel features such as the ability to kill bacteria.
"We're still in the Wild West mode of discovery," says Rutledge. "People are hypothesizing almost anything and giving it a try. We're still trying to figure out which ones are the payoff applications."
Rutledge has been one of the pioneers of electrospinning nanofibers since the nanotechnology boom of the late 1990s. Though he describes the actual electrospinning process as almost "a mundane thing," he and his colleagues have demonstrated a number of ways to create electrospun membranes with new and useful traits.
Electrospinning, the most general way to make a continuous polymer nanofiber, uses an electrical charge to draw the fiber from a liquid polymer. As a jet of charged fluid polymer sprays out the bottom of a nozzle, an electric field forces the stream to whip back and forth, stretching the fiber lengthwise so its diameter shrinks from 100 microns to as little as 10 nanometers.
The fiber forms a thin membrane as it hits the surface below the nozzle. These electrospun membranes have a unique combination of stretchiness and strength, and are easy to handle, making them suitable for a wide range of applications. Because the membranes are very porous (they contain 85 percent open space), they are already used as HEPA (high efficiency particle accumulation) filters, found in vacuum cleaners and military tanks.
In the past few years, Rutledge's team has produced several textiles that incorporate functional materials into the electrospun membranes. One major focus is designing textiles that can protect against toxic agents, both biological and chemical, by adding protective compounds to the polymer.
One such material, described in the journal Polymer last year, incorporates chlorhexidine, which can kill most bacteria. Rutledge's team is also working with oximes, a class of organic compounds that can break down organophosphates, chemicals that are the basis of many pesticides, insecticides and nerve gases. Materials such as these, developed in collaboration with Alan Hatton, the Ralph Landau Professor of Chemical Engineering, could be used to coat medical devices or create protective clothing for soldiers.
Rutledge and Paula Hammond, the Bayer Professor of Chemical Engineering, recently reported in the journal Advanced Materials a material embedded with titanium oxide, which can break down a variety of industrial chemicals, including organic compounds like phenols and allyl alcohol.
The fibers hold promise for development of new breathable, waterproof materials. Four years ago, Rutledge and Randy Hill of Dow Corning created an electrospun sheet that is extremely water-repellent. Such a material, described in the journal Langmuir, has the potential to become a cheaper alternative to GoreTex, which is made of Teflon -- a more expensive starting material than the polymers used to make electrospun fibers. More recently, working with MIT professors Karen Gleason, Robert Cohen, Gareth McKinley and Michael Rubner, Rutledge's group has demonstrated a variety of ways to render breathable electrospun fabrics water- and oil-repellent.
Rutledge is now working on electrospun fibers made of block copolymers that self-assemble into a collection of concentric cylinders within the fiber. Such fibers, made possible by a co-axial version of electrospinning technology that the group reported in 2004, could be used to impart color to fabrics without dye, or to create "wearable power" by combining electrodes and electrolytes into individual fibers.
"There are a lot of ways one can imaginatively think to use some of this stuff," says Rutledge.
