By Jack Mason
Small Times Correspondent
STONY BROOK, N.Y., May 1, 2002 — STAR Inc., a startup at the State University of New York, Stony Brook, is adapting a 19th century technology to create surgical material for the 21st.
STAR’s nanofiber membrane is a mesh of polymers designed to prevent body tissues from sticking together as they heal. It also breaks down in the body over time like biodegradable sutures.
Founded by Benjamin Chu, a distinguished professor of chemistry at Stony Brook with eight patents to his credit, STAR’s anti-adhesion material is made by “electrospinning.” The process, first patented in 1897, has been used in the textile industry since the 1930s.
STAR, an acronym for Stonybrook Technology and Applied Research, believes it can produce e-spun nanomaterial in commercial quantities on a bank of dispensing jets — a method it expects to patent.
Chu, along with co-founders Benjamin Hsiao, a chemistry professor, and Dufei Fang, a physicist, are experts in creating polymer fibers — such as those used in bulletproof vests.
About two years ago, Chu, now 70, started looking for an entrepreneurial challenge to cap his career in basic research. Commercializing the group’s process for electrospun nanofibers was a logical place to start, and STAR was born.
The university agreed to give their company exclusive license to the relevant patents, and they received a Phase 1 Small Business Innovation Research (SBIR) grant of more than $300,000 from the National Institutes of Health. The work has also been supported by the Army Research Office.
In its initial study, the group learned that surgical adhesions — scar tissue that formed in the abdomen or pelvis as the body heals after an operation — were a significant medical problem that can cause infertility or bowel obstructions.
Anti-adhesion materials made of cellulose or hyaluronan were already available from companies such as Johnson & Johnson and Genzyme Corp. Chu says doctors are unsatisfied with these existing materials because they tend to stick to a surgeon’s wet glove and don’t always work well inside a patient.
The nanomesh that the STAR team wants to commercialize is flexible and easier to hold. It may also be able to deliver antibiotics, painkillers or other medicines directly, and in smaller quantities, to internal tissues.
For example, as many as 40 percent of open-heart surgery patients experience abnormal cardiac rhythms after their operations. A nanostructured membrane like STAR’s, infused with an anti-inflammation agent such as ibuprofen and applied directly to heart tissue, has reduced the problem in animal studies.
The electrospinning process itself begins with a solution of polymers, long chains of molecules, pumped into an electrified metal nozzle. High voltage creates a cone of fluid outside the nozzle, and a tiny jet of material erupts, electrically attracted to a target surface a few inches below the nozzle.
In a few milliseconds, the electric field aligns the polymer molecules in the jetstream into fibrous strands, pulling and stretching the jet 1,000 times thinner than the micron-sized nozzle opening, to about a 150 nanometer diameter.
Oddly, the nanoscale fibers don’t follow a straight path down from the jetstream to the target surface. In fact, they spiral downward at about 300 miles per hour, traveling more than a mile in the space of inches to form an unwoven mesh like a thin pile of well-distributed spaghetti.
As the polymers make this strange, circuitous journey, the liquid solvent they were suspended in evaporates. The resulting material has an unusual, ephemeral feel, a tactile blend of paper, plastic and rubber. It isn’t sticky, and is fairly strong and difficult to tear.
The STAR team says it can produce its nanofiber material in bulk with its array of multiple jets. Now the group is working on expanding the flexibility of their process by altering the shapes of the jets, electrical fields and the composition of polymer solutions.
“Perhaps we can refine the material for specific effectiveness in different parts of the body,” said Chu. Different products could be tailored to stop adhesions on the liver or kidney. “We’re looking to learn from different doctors and surgeons how we can adapt or extend the use of the e-spun process for whatever they need.”
Other companies, such as eSpin Technologies, founded in Chattanooga, Tenn., in 1999, are also commercializing nanofibers made of organic and biological polymers for use in biomedical devices and filtration systems.
Donaldson Co. Inc., a Minneapolis-based maker of filtration systems, has patented its EON Nanofibers made with an electrospun process. Tim Grafe, director of new business, says the company produces about 10,000 square meters of nanofiber material a day. Donaldson’s nanofibers, which measure about 250 nanometers in diameter, are at work in factory dust collecting systems and filter air in the U.S. Army’s M1-A Abrams tanks.
He notes that Donaldson has been making electrospun fibers commercially since the 1970s. “We didn’t even call them nanofibers until a few years ago,” he said. Grafe says the company is forming technical and commercial relationships to develop applications including medical uses and drug delivery.
The STAR group is concentrating on its anti-adhesion business and getting SBIR funding for Phase II of the project. They say the material has proven effective at reducing tissue adhesions and adhesion strength in 200 rats. The next step would be Phase III clinical trials in humans. That expensive process is probably where STAR would seek a commercial partner and a professional management team.
“They’re going after a big enough problem, but the real question is how well will their nanofiber material work,” said Jason Friedman, a nanotechnology associate with JP Morgan Partners in New York. Friedman notes that other companies have been unsuccessful in solving the problem of surgical adhesions, and that the market would likely be skeptical until human trials showed significant success. “They also seem to have a single product more than a company strategy,” Friedman says.
Chu believes that STAR’s e-spun process will enable a range of products and is confident the anti-adhesion material will work. Who will help him bring it to market is less certain. “What we don’t want is to make a deal with a company that would just acquire our process to put it on a shelf to protect their own product,” says Chu. “We want to see this material put to use in helping people.”
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