This biodegradable piezoelectric pressure sensor could be used to monitor medical conditions before dissolving safely in a patient’s body. (Credit: Thanh Duc Nguyen)

A biodegradable pressure sensor could help doctors monitor chronic lung disease, swelling of the brain, and other medical conditions before dissolving harmlessly in a patient’s body.

The small, flexible sensor is made of medically safe materials already approved by FDA for use in surgical sutures, bone grafts, and medical implants. It is designed to replace existing implantable pressure sensors that have potentially toxic components.

A prototype sensor made by the lab consisted of a thin polymer film 5 mm long, 5 mm wide, and 200 µm thick. The sensor is made of two layers of piezoelectric PLLA film sandwiched between tiny molybdenum electrodes and then encapsulated with layers of polylactic acid or PLA, a biodegradable product commonly used for bone screws and tissue scaffolds.

The piezoelectric PLLA film emits a small electrical charge when even the most minute pressure is applied against it. Those small electrical signals can be captured and transmitted to another device for review by a doctor.