Enzymes prompt shape memory polymer to take form in medical applications

SMPs change shape in response to external stimuli like temperature changes or exposure to light. Biomedical applications include the use of SMPs as cardiovascular stents because they can be one shape for surgical insertion and another once positioned in a blood vessel. The warmth of the patient's body triggers the shape change.

Along with collaborators at Bucknell University in Pennsylvania, Syracuse University researchers have designed an SMP that can change its shape in response to exposure to enzymes and is said to be compatible with living cells. It requires no additional trigger, such as a change in temperature. Given these properties, it can respond to cellular activity like healing.

"The enzymatic sensitivity of the material allows it to respond directly to cell behaviour," said biomedical engineering Ph.D. candidate Shelby L. Buffington. "For instance, you could place it over a wound, and as the tissue remodelled and degraded it, the SMP would slowly pull the wound closed. It could be adapted to play a role in treating infections and cancer by adjusting the material's chemistry."