New Therapeutic Brain Implants to Eliminate Need for Surgery

Deadly and debilitating brain diseases often require invasive surgical implants to deliver electrical stimulation, a therapy known to slow tumor growth or ease conditions such as Alzheimer’s and multiple sclerosis. However, opening the skull carries major risks, high costs, and long recovery times, leaving many patients without access to neuromodulation. Clinicians also face challenges delivering implants to deep or delicate regions of the brain, especially when disease occurs across multiple microscopic sites. Now, researchers have developed a minimally invasive alternative using tiny wireless implants that move through the bloodstream and autonomously embed in target brain regions for treatment.

The technology, developed at the Massachusetts Institute of Technology (MIT, Cambridge, MA, USA; www.mit.edu), uses microscopic electronic devices fabricated through CMOS-compatible processes at MIT.nano facilities. Each device is roughly one-billionth the length of a grain of rice and is built from organic semiconducting layers between thin metallic films. Before injection, the free-floating electronics are chemically bonded to living immune cells, creating a hybrid able to travel through the body. The cells camouflage the electronics, allowing them to avoid immune attack and squeeze through the intact blood–brain barrier, a major challenge for therapeutics. In this study, the researchers integrated the devices with monocytes, which naturally migrate toward inflamed brain regions.

In mice, the tiny implants were successfully identified and self-implanted within a predefined brain region after a simple arm injection. Fluorescent labeling confirmed that the hybrids crossed the intact blood–brain barrier and accumulated in the correct tissue. Once in place, the devices were wirelessly powered using near-infrared electromagnetic waves, enabling localized neuromodulation within microns of the target. The results revealed that the implants could influence brain inflammation and operate deep within the brain while maintaining high energy-conversion efficiency.

The findings, published in Lab on a Chip, suggest broad potential for treating neurological diseases that are currently difficult or impossible to reach surgically. Because the cell-electronic hybrids maintain brain barrier integrity and integrate safely among neurons, they may allow clinicians to stimulate or modulate multiple microscopic tumor sites, including aggressive cancers such as diffuse intrinsic pontine glioma.

Their small size enables millions of self-implanting stimulation points shaped precisely to diseased regions without harming surrounding tissue. Researchers are also exploring different cell types to steer the devices to other targets, as well as integrating circuits for sensing, feedback, and synthetic neuron capabilities.

“Our tiny electronic devices seamlessly integrate with the neurons and co-live and co-exist with the brain cells, creating a unique brain-computer symbiosis,” said Deblina Sarkar, senior author. “We are working dedicatedly to employ this technology for treating neural diseases, where drugs or standard therapies fail, for alleviating human suffering, and envision a future where humans could transcend beyond diseases and biological limitations.”

Related Links:
MIT