Natural polyester makes new sutures stronger, safer

With the help of a new type of suture based on MIT research, patients who get stitches may never need to have them removed.

A biopolymer suture cleared last month by the FDA is made of materials that the human body produces naturally, so they can be safely absorbed once the wound is healed. They are also 30 percent stronger than sutures now used and very flexible, making them easier for surgeons to work with.

The sutures were developed by Tepha, Inc., a Cambridge company that hopes to use the same material to produce an array of absorbable medical devices, including stents, surgical meshes and possibly a heart valve scaffold, says Simon Williams, CEO of Tepha and a former MIT postdoctoral associate.

Williams said he envisions that the new sutures will be used for abdominal closures, which are prone to re-opening, and to stitch tendons and ligaments.

Developed using a method created at MIT, the absorbable sutures are the first made from material produced by genetically modified bacteria.

About 20 years ago, researchers in the laboratory of MIT biology professor Anthony Sinskey started swapping genes between different bacteria, hoping to achieve industrial production of desirable natural compounds synthesized by those bacteria.

The researchers focused their "biopolymer engineering" efforts on a group of genes that code for enzymes in a pathway that produces polyesters. Those polyesters can be broken down into metabolites naturally produced by humans, so they cause no harm when absorbed.

Once the genes were identified, they could be transferred into a strain of industrial E. coli that can produce large quantities of the strong, flexible polymer.

The FDA cleared the biopolymer sutures on Feb. 8, and Williams said Tepha plans to start marketing them soon, in partnership with another company.

"Not only is it technically and in an engineering sense a tremendous victory, but it's also a victory for society because this leads to new medical devices that can help people in new and novel ways," said Sinskey, who is one of the founders of Tepha and sits on its board of directors.

The new suture is the first of what the researchers hope will be many medical devices made from the natural polyesters.

"What we've found is that this one material seems to be finding a lot of use in different applications," because of its wide range of desirable properties, Williams said.

Tepha is now working on developing other medical devices, such as surgical meshes, multifilament fibers and stents. Ultimately, the researchers hope to develop an artificial scaffold that could be used to grow heart valves after being implanted in a patient, which would spare children with heart valve defects from undergoing repeated surgeries.
Tests of the device in animals have shown promise.

"We've been able to show we can produce a valve scaffold that functions better and can grow with the animal," Williams said. "If the valve can grow with the patient, you don't need the repeated surgeries."

Tepha, founded six years ago, is a spinoff of Metabolix, a company the researchers founded in 1992 to market bioplastics and biopolymer packaging materials.

Other current and former MIT researchers who helped develop the recombinant DNA methods used to create the biopolymer are JoAnne Stubbe, Novartis Professor of Chemistry and professor of biology, former postdoctoral associate Oliver Peoples and the late Professor Emeritus Satoru Masamune.

Source: MIT

Related stories:

Scientists create gecko-inspired bandage
MIT researchers and colleagues have created a waterproof adhesive bandage inspired by gecko lizards that may soon join sutures and staples as a basic operating room tool for patching up surgical wounds or internal injuries.
Engineers probe spiders' polymer art
A team of MIT engineers has identified two key physical processes that lend spider silk its unrivaled strength and durability, bringing closer to reality the long-sought goal of spinning artificial spider silk.
Genetic 'fingerprint' shown to predict liver cancer's return
Scientists have reached a critical milestone in the study of liver cancer that lays the groundwork for predicting the illness's path, whether toward cure or recurrence. By analyzing the tissue in and around liver tumors, an international research team has identified a kind of genetic "fingerprint" that can help predict if patients' cancers will return. The findings appear in the October 15 advance online edition of the New England Journal of Medicine and were made possible by a large-scale method for revealing genes' activity, which the researchers show can be applied to tissues that have been chemically preserved instead of frozen. This technical triumph promises to unlock biological information within millions of clinical samples previously intractable to genomic study.
At 2.8 km down, a 1-of-a-kind microorganism lives all alone
The first ecosystem ever found having only a single biological species has been discovered 2.8 kilometers (1.74 miles) beneath the surface of the earth in the Mponeng gold mine near Johannesburg, South Africa. There the rod-shaped bacterium Desulforudis audaxviator exists in complete isolation, total darkness, a lack of oxygen, and 60-degree-Celsius heat (140 degrees Fahrenheit).
CarTel uses WiFi to personalize commutes
(PhysOrg.com) -- Dozens of cars in the Boston area are testing the latest generation of an MIT mobile-sensor network for traffic analysis that could help drivers cut their commuting time, alert them to potential engine problems and more.
Report debunks China energy myth
A detailed analysis of powerplants in China by MIT researchers debunks the widespread notion that outmoded energy technology or the utter absence of government regulation is to blame for that country's notorious air-pollution problems. The real issue, the study found, involves complicated interactions between new market forces, new commercial pressures and new types of governmental regulation.
First atomic–scale compositional images of fuel-cell nanoparticles
(PhysOrg.com) -- In a step toward developing better fuel cells for electric cars and more, engineers at MIT and two other institutions have taken the first images of individual atoms on and near the surface of nanoparticles key to the eco-friendly energy storage devices.
Nanoscale carbon materials research wins the 2008 Julius Springer Prize for Applied Physics
Dr. Phaedon Avouris of IBM and Professor Tony Heinz of Columbia University were presented with the 2008 Julius Springer Prize for Applied Physics on 27 September 2008 during a day-long forum at Harvard University, attended by luminaries of the field. The Julius Springer Prize for Applied Physics recognizes researchers who have made an outstanding and innovative contribution to the field of applied physics. The forum was sponsored by the scientific publisher Springer.

News discussion:

General Science news