New nanofibers spun from a common blood protein to close wounds with minimal scarring

Nov 12 2008

Researchers at the Technion-Israel Institute of Technology have developed a strong, flexible, bio-material that may be used someday to close wounds with minimal scarring and rejection by the immune system.

Spun from a common blood protein, the material could be used to make the thin threads needed for wound sutures, larger dressings for wounds, and other anti-adhesion membranes used in abdominal surgery, according to Technion researchers Eyal Zussman, Arie Admon and their colleagues.

Since it is made entirely from biological material, with no synthetic additives, the material is more likely to integrate with the body's natural tissues and leave less of a scar, which could make it ideal for wound closure after Caesarean surgery or cosmetic procedures, Zussman said.

Dr. Miriam Rafailovich, a materials science and engineering research at the State University of New York at Stony Brook, said the new material is not overly adhesive, which might make it useful in treating burns. "I see all kinds of applications for it where you don't want a dressing to stick to a wound," she noted.

In the journal Biomacromolecules, Zussman and colleagues discuss how they turned the globular protein bovine serum albumin into thick mats using electrospinning, a technique that uses an electrical charge to pull and stretch liquid droplets into nano-sized fibers.

Many researchers have used the technique to spin fibers from organic materials, hoping to mimic the strength and elasticity of natural substances such as spider silk, for example. However, it has been a challenge to spin organic materials into stable threads, making it necessary to spin a blend of artificial and natural molecules.

But these artificial elements are exactly the kind of thing that the body's immune system might reject in wound repair, so the Technion researchers looked for organic molecules that could be spun without additives.

Serum albumin "was selected under the assumption that, being one of the most abundant proteins in the body, nanofibers made from serum albumin would be regarded as being less foreign to the body and therefore less likely to be rejected," Zussman explained.

During electrospinning, certain chemical bonds are broken and re-linked in a new pattern in the globular protein, which gives it stability and flexibility in a linear shape, the researchers discovered.

Most proteins adopt a coiled shape, which scientists attempt to "straighten out" by adding artificial molecules to the protein during electrospinning. "What the Zussman group figured out-the ingenuity of what they did-was to find a way to break the protein's bonds and turn it into a linear polymer" without using additional molecules to force it into a fibrous shape, Rafailovich explained.

The Technion researchers are planning to test their electrospinning technique on other proteins, Zussman said.

The Technion-Israel Institute of Technology is Israel's leading science and technology university. Home to the country's winners of the Nobel Prize in science, it commands a worldwide reputation for its pioneering work in nanotechnology, computer science, biotechnology, water-resource management, materials engineering, aerospace and medicine. The majority of the founders and managers of Israel's high-tech companies are alumni. Based in New York City, the American Technion Society (ATS) is the leading American organization supporting higher education in Israel, with 22 offices around the country.