The prototype fuel cell — wrapped in fleece — is slightly larger than a thumbnail. [Image courtesy of Fussenegger Lab/ETH Zurich]
By combining the fuel cell with artificial beta 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 thinks they may have found a new way to produce that energy.
Martin Fussenegger, a professor of biotechnology and bioengineering, leads the team at ETH Zurich in Switzerland. 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. The electrode splits glucose into gluconic acid and a proton, generating electricity and 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.”
This could be a real game changer for diabetic folks, by virtue of automating at least part of the required therapy. This could thus also be a high=in=demand product with a very long product lifetime.
Two real barriers exist, first being FDA approval, and the larger barrier being the development of a process for production that would have an acceptable production yield at an acceptable cost.
Just because something can be produced in a laboratory does not mean it can be produced en-mass. I have seen the announcements of many great discoveries that never made it to market.