Power from the body itself
Implants run on batteries that eventually die. Engineers at the University of Massachusetts Amherst grew living human heart tissue around a mesh of tiny generators, and each heartbeat bent the generators enough to produce an electrical pulse, Earth.com reported on October 23. The team’s calculation puts the output at more than ten times the energy for the device’s size compared with earlier implanted harvesters. None of it has been tried in a body.
Design
The mesh is about 7 by 8 millimeters and roughly 78% open space. It carries 64 strips of lead zirconate titanate, a ceramic that generates voltage when bent; groups of four form one harvester, sealed from wet tissue by thin plastic. Human stem cells were turned into heart muscle cells and seeded onto it, forming a sheet that wrapped around the ribbons and beat every two to three seconds. Senior author Jun Yao describes a shift from a centralized to a distributed, biology-inspired approach.
Numbers
The first version produced about 9 millivolts per beat per harvester. After the team thickened the coating only around the strips, output rose to an estimated 450 to 750 millivolts. Energy per beat was about 7 trillionths of a joule per harvester, each about the size of one cell. New Atlas reports the work appeared in a peer-reviewed journal and that the mesh could eventually power implants such as pacemakers.
What remains
Everything occurred in a thin sheet of lab-grown tissue. It has not been shown inside a living body or proven to replace a pacemaker battery. Still, the concept points toward battery-free sensors.
Practical takeaways
- This is an in-vitro proof of concept.
- Distributed harvesting reduces bulk compared with single large harvesters.
- Look for animal studies as the next milestone.
Bottom line
Embedding generators into tissue is a clever way to avoid battery bulk. The leap from a dish to a body is the hard part.