Scientists have created a new glucose-powered implantable fuel cell that may be used to power highly efficient brain implants of the future, giving paralyzed patients the ability to move their arms and legs again.
Researchers led by Rahul Sarpeshkar, associate professor of electrical engineering and computer science at MIT, and Benjamin Rapoport, former graduate student in Sarpeshkar's lab, fabricated the fuel cell on a silicon chip, which enabled it to be combined with other circuits that would be needed for the brain implant.
Researchers said that the idea of the glucose fuel cell is not new; in fact scientists demonstrated that a glucose fuel cell could power a pacemaker, but the idea was abandoned for lithium-ion batteries, which provided significantly more power per unit area than glucose fuel cells.
Another reason why the idea was abandoned was because those glucose cells were impractical for long-term implantation because they eventually caused to function efficiently.
The new twist to the latest MIT sugar-powered cell, fabricated from silicon, using the same technology behind semiconductor electronic chips, is that it has no biological components. It is made out of a platinum catalyst that strips electrons from glucose, mimicking the activity of cellular enzymes that break down glucose to generate ATP or cellular energy.
"The glucose fuel cell, when combined with such ultra-low-power electronics, can enable brain implants or other implants to be completely self-powered," Sarpeshkar said in a statement.
Researchers said that the fuel cell is capable of generating up to hundreds of microwatts, which is enough to power an ultra-low-power and clinically useful neural implant.
"It will be a few more years into the future before you see people with spinal-cord injuries receive such implantable systems in the context of standard medical care, but those are the sorts of devices you could envision powering from a glucose-based fuel cell," Rapoport said in a statement.
Rapoport predicts that the sugar-powered fuel cell could get all the power it needs just from the cerebrospinal fluid (CSF) that bathes the brain and protects it from knocking into the skull. He also said that there are very few cells located in the protective fluid, so he believes that it would be highly unlikely for the power cell to provoke an immune response.
Furthermore, because the cell only requires a small amount of energy, Rapoport said that the device's impact on the brain will be small.
"It's a proof of concept that they can generate enough power to meet the requirements," Karim Oweiss, an associate professor of electrical engineering, computer science and neuroscience at Michigan State University, said in a statement. He added that the next step will be to show that the fuel cell can work in a living animal.