Researchers at ETH Zurich have developed an experimental electronic implant that uses electricity to convert excess blood sugar into gluconate, a substance the body can eliminate through urine. The device addresses a limitation of insulin therapy, which reduces blood sugar but does not prevent excess glucose from being stored as fat.
The implant contains a catalyst made from graphite felt covered with gold and platinum nanoparticles. This inorganic material requires no living cells or enzymes to function. An electronic controller housed in 3D-printed casing receives power wirelessly at 13.56 MHz, a frequency designated for medical applications.
A glucose sensor worn on the body continuously measures blood sugar levels. When glucose rises too high, the sensor activates the implant through a smartphone or smartwatch via Bluetooth. The electrical current triggers the catalyst to convert glucose into gluconate. Once blood sugar returns to the target range, the implant shuts down automatically. Martin Fussenegger, a professor in the Department of Biosystems Science and Engineering at ETH Zurich in Basel, led the research team.
In laboratory tests using a 5-liter glucose solution approximately equivalent to adult human blood volume, the catalyst successfully converted glucose at that scale. The researchers then implanted the system in diabetic mice. Over six weeks, the device regulated blood sugar levels precisely and the mice lost weight. The implant functioned reliably and showed no signs of tissue damage.
"The system operates at a very low voltage, and our experiments showed no evidence of tissue damage from either electrical or thermal effects," Fussenegger said.
The implant has not been tested in humans. Fussenegger stated that the team's next objective is to develop the experimental implant into a medical device suitable for further development and eventual clinical testing.