Diagnostic or therapeutic electronic devices implanted into patients could now be made fully bio-degradable, thus avoiding the need for repeated surgical interventions. The biodegradable approach may also be used to combat the problem of electronic waste.
A team of scientists at the University of Illinois, USA, has been working on the design of small electronic devices that can be implanted into the human body for a specific amount of time and programmed to dissolve safely into the body’s fluids when no longer needed. This type of ‘transient’ device is already in use in medical procedures, such as absorbable sutures. The thread used for this type of suture is broken down progressively by bodily processes. In order to develop these bio-degradable electronic devices, the scientists had to rethink each component of the implant. They combined bio-compatible materials such as silicon for the integrated circuit, magnesium for the conductor, and layers of magnesium oxide and silk, whose structure and thickness will determine the rate of dissolution in the body.
Conclusive lab tests
When the outer ‘encapsulating’ layer is exposed to water or bodily fluids, it dissolves. Thirty minutes later, the electronic connections start to dissolve in their turn and the device ceases to function. Such transient devices represent a major advance in medicine. They could help, for example, to ease a patient’s pain, or fight an infection, without the need for further surgery, which carries a risk. A multidisciplinary research team led by John A. Rogers, Engineering Professor at the University of Illinois, carried out a series of tests on laboratory rats. The tests were conclusive. The transient devices, which produce local heat, prevented the formation of bacteria while helping to increase bone mass and assisting production of scar tissue.
Dissolving cameras and mobile devices?
Professor Rogers hopes to extend his research to other fields. What should be done for instance with your mobile phone when it’s broken, or your digital camera when it doesn’t work anymore? It’s often less costly to buy a new item than have it repaired and our first thought may well be to throw it away. But what if obsolete objects could simply be made to disappear? It’s arguable that some companies might abuse biodegradable technology, forcing their customers to keep buying new equipment. But on the positive side, this new approach could provide a solution to the problem of massive amounts of electrical goods waste polluting the four corners of the globe, arousing fierce opposition from the ecologically-minded.