Biological fuel cells powered by patients’ own bodies could provide an ‘inexhaustible source’ of power for pacemakers and other implants.
The work is being carried out by a research team at the Department of Microsystems Engineering (IMTEK), which is part of Freiburg University in Germany.
Currently, there is no ideal method for supplying implantable medical microsystems with electrical energy. The batteries of a pacemaker, for instance, need to be replaced after roughly eight years — meaning a strenuous and expensive surgical intervention for the patient.
An alternative approach is to use rechargeable batteries; however, the necessity to recharge the batteries greatly reduces the patient’s quality of life.
Now, a team led by Dr Sven Kerzenmacher of IMTEK is researching the possibility of using of implantable glucose fuel cells on the basis of noble metal catalysts such as platinum.
Such catalysts are particularly suitable for use in implant systems thanks to their long-term stability and the fact that they can be sterilised.
In the future, systems equipped with these fuel cells could be supplied with power by way of a continuous electrochemical reaction between glucose and oxygen from the tissue fluid.
Kerzenmacher and his team aim to apply a thin coat of the fuel cells they have developed to the surface of the implant. The advantages of this technique over existing technologies stem from the fact that the fuel cells are only half as thick while delivering a 30 per cent increase in performance. Moreover, platinum electrodes are not sensitive to unwanted chemical reactions such as hydrolysis and oxidation.
Kerzenmacher’s research group consists of biologists, chemists and engineers, all of whom are currently developing new materials and techniques to improve the performance of the fuel cells.