One of the problems with implanted medical devices is that their batteries eventually run out and they have to be replaced in a surgical procedure. This may change in the near future. Researchers have, for the first time, successfully implanted sugar-fueled cells in living rats. Their results suggest that it may one day be possible to use the body’s own glucose and oxygen supplies to power medical implants.

 

The idea of powering implants with the body’s own energy stores is not new but previous attempts to develop glucose biofuel cells failed in vivo because the enzymes needed to catalyze oxidation were inhibited by charged particles in the fluid surrounding cells, or the need for low pH conditions.

 

Philippe Cinquin and his research team from Joseph Fourier University in Grenoble, France, found that they could overcome this obstacle by encasing the enzymes in graphite discs that were then place into dialysis bags. Glucose and oxygen flow into the device where the enzyme catalyzes the oxidation of the glucose to generate electrical energy. The enzyme stays separated from the cellular environment.

 

The researchers then implanted the device in the abdominal cavity of two rats and were able to generate up to 6.5 microwatts peak power and a peak specific power of 24.4 microwatts per milliliter, better than pacemakers’ requirements, and “paving the way for the development of a new generation of implantable artificial organs, covering a wide range of medical applications,” according to the authors of the paper published in PLoS One.

 

The French researchers said they expect to be able to improve output to well above the 10 microwatt threshold through the use of other enzymes and mediators, enough to power many medical devices, including artificial organs.