Researchers create implantable fibers that may detect disease

MIT researchers have developed a stretchy optical fiber in which they have injected multiple organic dyes (yellow, blue, and green regions). In addition to lighting up, the dyes act as a strain sensor, enabling researchers to quantify where and by how much a fiber has been stretched. (Courtesy of the researchers)

Imagine if the earliest signs of disease visibly presented in patients, thereby helping doctors actively monitor the progression of their symptoms. This ability may not be far off: Researchers at the Massachusetts Institute of Technology and Harvard Medical School have developed a stretchy, biocompatible optical fiber that aims to do just that.

The fiber is made of hydrogel, an elastic, rubbery material composed mostly of water, and could bend and twist in a patient’s body without breaking down, according to an MIT news release.

Researchers hope the fibers can be implanted in the body to deliver therapeutic pulses of light when the fiber senses when and where it’s being stretched. The fibers could be embedded or fitted along the length of a patient’s limb to monitor for signs of improving mobility.

“When you stretch a certain portion of the fiber, the dimensions of that part of the fiber changes, along with the amount of light that region absorbs and scatters, so in this way, the fiber can serve as a sensor of strain,” MIT graduate student Xinyue Liu said in the news release.

MIT graduate student Hyunwoo Yuk described the technology as “a multistrain sensor through a single fiber” that can act as “an implantable or wearable strain gauge.”

Another potential use for the fibers is as a sensor for disease.

“We may be able to use optical fibers for long-term diagnostics, to optically monitor tumors or inflammation,” Xuanhe Zhao, the Robert N. Noyce Career Development Associate Professor in MIT’s Department of Mechanical Engineering, said in the news release. “The applications can be impactful.”

The research was published Oct. 7 in Advanced Materials.