Implanting chemical sensors directly into the body for long-term monitoring of glucose and other important molecules could prove extremely beneficial, especially to diabetics that need to keep a continuous and close eye on their sugar levels. A major problem that prevents the development of practical monitoring implants, called “biophouling”, is due to the body’s own immune system attacking foreign objects and plugging up any sensor components that are exposed. Researchers have spent considerable effort over the years attempting to design materials that would not trigger an immune response, but it turns out that the body has a mind of its own and is not easy to fool.
Researchers at Texas A&M University decided to take another approach and build a special membrane that would protect an implanted sensor while being able to shake off any accumulation on its surface. The membrane is made of a heat responsive hydrogel that contracts and expands due to temperature changes. By carefully applying heat to the membrane, it changes shape and any cells and proteins attached to its surface naturally let go.
Here’s a video report from Texas A&M:
Study abstract in Soft Matter: Thermoresponsive nanocomposite double network hydrogels