Image: ' Science

Scientists have developed a smart suture that can tie itself, a new study shows. Moreover, the thermoplastic threads, which change their shape in response to temperature, can slowly break down in the body, thus eliminating the need for removal later.

In a report released online today by the journal Science, Andreas Lendlein of the Institute for Technical and Macromolecular Chemistry in Germany and Robert Langer of the Massachusetts Institute of Technology describe stiches made of so-called shape-memory polymers. The polymer they developed consists of building-block segments linked together in chains. Within these chains, the researchers coupled two types of segments having different thermal properties. The combination resulted in a material that forms a transitory shape at one temperature, and a permanent one at a higher temperature. "We created a temporary shape in the form of an elongated fiber, which was then used to loosely tie a suture to close a wound on a rat," Langer explains. When the researchers increased the temperature, the suture material shrank, resulting in a knot with optimum force to close the cut.

The scientists have high hopes for their shape-shifting sutures. They have already formed a company, mnemoScience GmbH, to develop their discovery. Indeed, they conclude that their latest work "suggests that this type of material has the potential to influence how implants are designed and could enable new surgical devices in the future."