MIT Develops Injectable, Cell‑Coated Brain Chips That Navigate to Targets in Mice

MIT researchers build microscopic, injectable brain chips that home to targets in mice

Imagine placing a brain implant without opening the skull — instead delivering a tiny device through a simple injection. Researchers at the Massachusetts Institute of Technology have developed microscopic, wireless electronic chips coated with living cells that can travel through the bloodstream and autonomously lodge in specific brain regions in mice.

In laboratory experiments the team reported that these devices — each roughly a billionth the size of a grain of rice — can locate and migrate to designated brain areas without direct human guidance. Once in place, the chips can provide targeted electrical stimulation similar to deep brain stimulation (DBS), a therapy currently used for conditions such as Parkinson's disease, multiple sclerosis, epilepsy and depression.

Cell coating and immune camouflage. Before injection, researchers integrate the tiny electronics with living cells. That cell coating appears to shield the devices from immune attack, allowing them to circulate in the blood and cross an intact blood‑brain barrier to reach brain tissue. According to senior author Deblina Sarkar, the cell‑electronics hybrid combines the flexibility of electronics with the transport and sensing capabilities of living cells.

Precision targeting and activation. The technology could offer much finer spatial precision than conventional implants because of the devices' tiny size. Different cell types might be used to direct chips to particular brain regions, depending on the disorder being treated. After the devices reach their target, a clinician would use externally applied electromagnetic waves to power and activate them, enabling electrical stimulation of nearby neurons.

"Our tiny electronic devices seamlessly integrate with the neurons and co-exist with the brain cells," said Deblina Sarkar, associate professor at the MIT Media Lab and Center for Neurobiological Engineering. "We are working to apply this approach to neural diseases where drugs or standard therapies fail."

Early results and caveats. In the mouse study the injectable chips also reduced brain inflammation when used for deep brain electrical stimulation. The work was published in Nature Biotechnology. However, authors and outside experts caution that these results are preclinical: much more research is required to confirm safety, control migration, assess long‑term effects, and demonstrate efficacy in larger animals and humans. Regulatory review, manufacturing scale‑up and ethical considerations will also shape any path to clinical use.

Potential implications. If the approach proves safe and effective in further testing, it could reduce the need for invasive brain surgery for some therapies and lower costs and risks associated with traditional implants. Researchers also suggest the platform might eventually be adapted for other organs or to deliver sensing and therapeutic functions beyond neuromodulation.

Note: Findings to date are limited to laboratory mice. Clinical translation will require extensive additional studies.