A team of researchers developed an implantable fuel cell that uses excess glucose from tissue to generate electrical energy.
By combining the fuel cell with artificial data cells, the team produced insulin with the touch of a button. This effectively lowered blood glucose levels like the natural process in the pancreas. Given that current treatments for diabetes often include insulin pumps that require a reliable energy supply, the team feels it may have found a new way to produce that energy.
Martin Fussenegger leads the team at ETH Zurich in Switzerland. There, he serves as a professor of biotechnology and bioengineering, according to a post on the university website. Their research has been underway for years, with early test results published in Science in 2016.
“Many people, especially in the Western industrialized nations, consume more carbohydrates than they need in everyday life,” Fussenegger said. “This gave us the idea of using this excess metabolic energy to produce electricity to power biomedical devices.”
Developing the fuel cell that turns glucose into electricity
Fussenegger’s team created an anode at the heart of the fuel cell. This electrode is made of copper-based nanoparticles, specifically created for this application. It features copper-based nanoparticles and splits glucose into gluconic acid and a proton. This generates electricity, setting an electric circuit in motion.
The researchers wrapped the anode in nonwoven fabric, coated with alginate, an algae product approved for medical use. Fussenegger and the team say it resembles a small tea bag they can implant under the skin. The alginate soaks up body fluid and allows glucose to pass from the tissue into the fuel cell.
In the next step, the team coupled their fuel cell with a capsule containing artificial beta cells. Through stimulation, these can produce and secrete insulin using electric current or blue LED light. This system combines sustained power generation and controlled insulin delivery. As soon as the fuel cell registers excess glucose, it begins generating power. It then uses electrical energy to stimulate cells, produce and release insulin into the blood.
Once blood sugar falls below a threshold to a normal level, the system stops producing electricity and insulin.
The electrical energy the fuel cell produces can even communicate with external devices like smartphones. This could allow users to adjust their system through a corresponding app. A doctor could also access it remotely and make adjustments.
“The new system autonomously regulates insulin and blood glucose levels and could be used to treat diabetes in the future,” Fussenegger noted.
With the research resulting in a prototype, the team can’t quite yet develop it into a marketable product.
“Bringing such a device to market is far beyond our financial and human resources,” Fussenegger explained. This would call for an industry partner with the appropriate resources and know-how.”