While most implanted drug delivery devices corrode when implanted in the body, a new type of “biobattery” takes advantage of the corrosion and uses the corrosion process as a time-release system.
When the magnesium polymer is exposed to bodily fluids, a very predictable and stable electric current is generated. This current reverses the electrostatic charges that bind the drug to the polymer aspect of the battery. With the charges reversed, the drugs are released into the body to do their thing.
This battery actually can be used with those implants in the body that already corrode, such as Titanium hips or knees.