Standard brain implants use electrodes that penetrate the gray matter to stimulate and record the activity of neurons. These usually need to be installed through a surgical procedure. To meet that need, a team of researchers led by Deblina Sarkar, an electrical engineer and MIT assistant professor, developed microscopic electronic devices hybridized with living cells. Those cells can be injected into the circulatory system with a standard syringe and will travel in the bloodstream before implanting themselves in target brain areas.
“In the first two years of working on this technology at MIT, we had 35 grant proposals rejected in a row,” says Sarkar. “We got comments from reviewers that our idea was very impressive, but it was impossible.” She admits that the proposal sounded like something you might find in science fiction novels. But after more than six years of research, he and his colleagues achieved it.
nanobot problems
In 2022, after Sarkar and his colleagues collected preliminary data and achieved some promising results with their cell-electronics hybrid, the team proposed the project for the National Institutes of Health Director’s New Innovator Award. The first time, after 35 rejections, it made it through peer review. “We got the highest impact score ever,” says Sarkar.
The reason for that score was that his technique solved three extremely difficult problems. The first, obviously, was to create functional electronic devices smaller than cells that could circulate in our blood.
“Previous explorations, which did not have much success, relied on inserting magnetic particles inside the bloodstream and then guiding them with a magnetic field,” explains Sarkar. “But there is a difference between electronics and particles.” Electronics made using CMOS technology (which we use to make computer processors) can generate electrical power from incoming light in a similar way to photovoltaics, as well as perform the calculations needed for more intelligent applications such as sensing. On the other hand, particles can only be used to stimulate cells to a limited extent.