UMass Amherst Engineers Design Mesh for Battery-Free Implantable Electronics
- Humans have long dreamed of a future where certain electronics can augment our abilities, says Jun Yao, associate professor in UMass Amherst's Riccio College of Engineering and the...
- Engineers at the University of Massachusetts Amherst have designed an ultrathin, flexible mesh that integrates electronics with human cells to supply a continuous electrical current without batteries.
- Pacemakers, implantable defibrillators, deep brain stimulators, cochlear implants, and health monitors rely entirely on external or centralized power supplies.
Humans have long dreamed of a future where certain electronics can augment our abilities,
says Jun Yao, associate professor in UMass Amherst’s Riccio College of Engineering and the paper’s senior author.
Engineers at the University of Massachusetts Amherst have designed an ultrathin, flexible mesh that integrates electronics with human cells to supply a continuous electrical current without batteries. Published in Science Advances, the study addresses the core limitation of implantable medical devices: the bulky, finite nature of standard power sources.
Building a cellular power plant
Pacemakers, implantable defibrillators, deep brain stimulators, cochlear implants, and health monitors rely entirely on external or centralized power supplies. Batteries eventually run out of energy, and shrinking them to fit flexible form factors severely reduces their charge capacity. To bypass this bottleneck, the research team looked to biological systems where energy generation is decentralized.
Our bodies are 24/7 power plants. Every single cell produces its own power,
says lead author Siqi Wang, a Ph.D. student in the Riccio College of Engineering. Human cells generate electrical impulses through nerves and mechanical energy through muscle contractions, creating a distributed power network across the entire system.
Integrating PZT ribbons with cardiac cells
To capture this biological energy, the researchers built an array using thin ribbons of lead zirconate titanate, known as PZT, which converts mechanical energy into electricity. They placed these ribbons onto an ultrathin, ultraflexible polymer platform. The team then seeded the platform with human cardiac cells, which grew and meshed naturally into and around the PZT material.
The resulting biomaterial moves and mimics human tissue while functioning as a permanent power generator. According to the study, the device generated ten times more power density than conventional centralized power systems of a comparable volume. Because the films are ultrathin, multiple layers can be stacked to increase total power output while keeping the implant entirely noninvasive.
Cellular devices improve biocompatibility in laboratory settings
The beauty of this system is how noninvasive and powerful it is,
Yao says. Our bodies want to reject systems that come with bulk batteries, but when the device exists at the cellular level, you get vastly improved biocompatibility.
Yao emphasizes that the research currently exists only in the laboratory setting. The development builds upon previous work from Yao, which demonstrated a mesh capable of growing with and monitoring heart tissue, an artificial neuron that communicates directly with human cells, and methods for harvesting clean energy from the air.
We wanted to shift this traditional, centralized paradigm to something more distributed and modeled on biology.
Jun Yao