Doctors who want to be able to monitor a patient’s vital signs or easily deliver treatments could soon have a new tool at their disposal: a new breed of electronic implants can be inserted under the skin, and they eventually melt away once they’ve served their purpose and treatment is complete. Biodegradable silicon chips have already been available since 2012, but unfortunately there’s been no easy way to power the devices. Some of them use induction coils to draw wireless power from external sources, but devices deep within tissue or under the bone haven’t been able to effectively use this technology. Now, thanks to a newly-designed, biodegradable battery, these more complex devices might soon be a reality.
The batteries, which were described in last week’s issue of Advanced Materials, are made of magnesium and iron, molybdenum, or tungsten. All of these metals are able to slowly dissolve in the body and will have no negative effect in low concentrations. The system is completed with a saline solution and biodegradable plastic packaging. These batteries could also be used in environmental cleanup to power chemical sensors which would simply dissolve when no longer needed.
While this is a huge step forward in battery technology for medical devices, more work needs to be done. So far, the batteries can only maintain steady output for a couple of days. Researchers are hoping that by increasing the surface area of the magnesium foil, they’ll be able to enhance the amount of power the batteries can generate. If the batteries could last long enough, they could expand treatment options for patients who suffer specific acute medical problems like epilepsy by dispensing drugs automatically as needed.