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Deblina Sarkar is building microscopic machines to enter our brains

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Deblina Sarkar makes little machines, for which she has big dreams. The machines are so little, in fact, that they can humbly inhabit living cells. And her dreams are so big, they may one day save your mind.

Sarkar is a nanotechnologist and assistant professor at MIT. She develops ultratiny electronic devices, some smaller than a mote of dust, that she hopes will one day enter the brain. SheтАЩs also a fan of Kung Fu movies and likes to dance her own twist on bharata natya, a classical Indian dance form. Occasionally she goes hiking with her graduate students, once taking them as far as Yellowstone. Building camaraderie is vital, Sarkar says. But тАЬIтАЩm probably working day and night on my research,тАЭ she confesses. тАЬThere is an urgent problem at hand.тАЭ

That problem is AlzheimerтАЩs disease, ParkinsonтАЩs disease and other neurological afflictions that assault the minds of millions of people worldwide. SarkarтАЩs solution: Employ minute machines to detect and reverse these disorders.

тАЬShe was always interested in applying тАж electronics to biological systems,тАЭ says collaborator and bioengineering researcher Samir Mitragotri of Harvard University, who has known Sarkar for about a decade and was on her thesis committee. She envisions using her tools to тАЬtransform how people are conducting biology,тАЭ he says, тАЬbridging the worlds.тАЭ

A focus on nanoelectronics

Born in Kolkata, India, Sarkar credits both of her parents as early inspirations. Her boldness as a researcher comes from her mother, who as a young woman defied social norms in her village by working to fund her own education and speaking out against the dowry system. Meanwhile, SarkarтАЩs father sparked her fascination for engineering.

At the age of 15, he abandoned his dreams of becoming an engineer to find other jobs; he needed to support his parents and the rest of his family after his father, an Indian freedom fighter, was shot in the leg and could no longer work. Still, Sarkar recalls her father finding time for his passion, fashioning devices to make home life more convenient. These included an electricity-free washing machine and vehicles that could freight hefty loads down local byroads to their house.

тАЬThat got me very, very interested in science and technology,тАЭ Sarkar says. тАЬEngineering specifically.тАЭ

After earning a bachelorтАЩs degree in electrical engineering from the Indian Institute of Technology Dhanbad, Sarkar moved to California to study nanoelectronics at the University of California, Santa Barbara. There, she tested new ways to create nanodevices that could reduce the amount of power consumed by computers and other everyday electronics.

One standout device Sarkar developed during her graduate work was a transistor that reduced the amount of power lost as heat by 90 percent compared with some of todayтАЩs most common silicon transistors (SN: 3/18/22). For the breakthrough, UC Santa Barbara awarded SarkarтАЩs Ph.D. dissertation the Lancaster Award for its impact in advancing math, physical sciences and engineering.

When tech meets the body

Along the way, Sarkar became fascinated with the brain, which she calls тАЬthe lowest energy computer.тАЭ A project imaging amyloid-beta plaques as a postdoc at MIT opened the door to fusing her dual interests, and she stayed on as an assistant professor to found the Nano-Cybernetic Biotrek group. Her group develops nanodevices that can interface with living cells, and тАЬneuromorphicтАЭ computing devices, which have architectures inspired by the human brain and nervous system. ┬а

So far, the groupтАЩs most innovative device may be the Cell Rover, a flat antenna that could monitor processes inside cells. For a study reported in 2022, Sarkar and her colleagues used magnetic fields to finesse a Cell Rover, roughly the size of a tardigrade, into a mature frog egg cell. The team demonstrated that when stimulated by a magnetic field created by an alternating current, molecules in the nanodevice vibrated at frequencies safe for living cells. Using a wire coil receiver, the researchers were able to detect how those vibrations affected the deviceтАЩs own magnetic field, thus showing it could communicate with the outside world. Cell Rovers could be outfitted with films that latch onto and detect select proteins or other biomolecules.

Sarkar envisions using the device to spot misfolded proteins in the brain that may be early signs of AlzheimerтАЩs disease. Today, memory loss is the only way to know a living person has AlzheimerтАЩs, but by then, the damage is irreversible, Sarkar says. Cell Rovers could also be paired with nanodevices that harvest energy from and electrically stimulate cells, opening the door for new types of brain electrodes and subcellular pacemakers. Or fleets of remotely controlled devices could replace invasive surgeries тАФ detecting a small tumor growing in the brain, for example, and maybe even killing it.

Two illustrations of the Cell Rover. The top image has several small blue and red rectangles randomly scattered in a white box. The bottom image has those same small rectangles in an organized grid, six across and four down.
When left undisturbed, the magnetic molecules in the Cell Rover are randomly oriented (top). But when subjected to a magnetic field produced by an alternating current, they will repeatedly flip around and reorient themselves (bottom). Those movements strain the device and cause it to vibrate in ways the researchers can detect.B. Joy et al/Nature Communications 2022When left undisturbed, the magnetic molecules in the Cell Rover are randomly oriented (top). But when subjected to a magnetic field produced by an alternating current, they will repeatedly flip around and reorient themselves (bottom). Those movements strain the device and cause it to vibrate in ways the researchers can detect.B. Joy et al/Nature Communications 2022

SheтАЩs essentially establishing a new field of science, at the intersection of nanoelectronics and biology, Mitragotri says. тАЬThere are many opportunities for the future.тАЭ

One day, Sarkar hopes to insert nanodevices between human neurons to boost the computing speed of the fleshy processor already in our skulls. Our brains are remarkable, she says, but тАЬwe could be better than what we are.тАЭ

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