After undergoing orthopedic surgery, patients are typically expected to take part in physical rehabilitation as part of their recovery. Yet, with the untold impact of pressure and strain on the the new components, scientists have long been in search of a better method for measuring such impact. Researchers from Stanford University have developed an implantable sensor designed to both accurately measure strain and pressure and then dissolve once it has outlived its usefulness.
Overcoming both performance and biocompatibility issues, the research team has found a solution that would make a second surgery to remove an implantable sensor wholly unnecessary.
Created by stacking two sensors — one for measuring strain, the other for measuring pressure — the sensor structure consists of two kinds of biodegradable and biocompatible polymers featuring magnesium electrodes.
Once completed, the multi-layer sensor was implanted in the back of a rat where it was capable of measuring strains (as small as 0.4 percent) and pressures (as small as 12 Pa) without interference. Likewise, the sensor worked as intended even during the decomposition phase up until it was no longer of any use.
The team reported that, apart from a minor amount of inflammation at the start, the rat did not experience any negative impact from the implantable sensor.
The research is published in the journal Nature Electronics.