UMass Amherst researchers develop heart tissue energy mesh

Implantable medical devices such as pacemakers and deep brain-stimulating tools currently rely on bulky power sources like batteries to maintain function. However, these batteries degrade over time, and attempts to shrink their size or increase flexibility inevitably reduce their energy capacity, resulting in frequent surgical replacements for patients.

To overcome this limitation, researchers at the University of Massachusetts Amherst have engineered a thin, flexible electronic mesh that allows human heart muscle cells to grow and interweave within it. This approach aims to convert the natural contraction force of the tissue into electrical energy, potentially eliminating battery constraints in wearable and implantable medical devices.

Stock photo for illustration only, not from the actual event

Rather than attaching a single large power generation unit to an organ, the research team chose to distribute numerous tiny power-generating units throughout the tissue. They termed this concept a biohybrid mesh harvester, which successfully merges electronic materials with living cells. The prototype mesh measures 7 by 8 millimeters and contains a total of 64 power-generation units.

Each generation unit features a thin polymer ribbon approximately 20 micrometers wide, closely matching the dimensions of a heart muscle cell. Embedded within the ribbon are platinum wires and PZT ceramic strips, which possess the unique property of generating electricity when bent or compressed. Because of this microscopic size and flexibility, the mesh remains pliable instead of forming a rigid block next to the cells.

"This concept is different from a battery because it does not have a single power source, but rather allows multiple tissue points to generate electricity together, much like how the body does not rely on just one power plant."

Jun Yao, Associate Professor of Electrical and Computer Engineering, UMass Amherst

During initial experiments, the team cultured human heart cells derived from stem cells onto the mesh for 15 days until the cells developed into a tissue sheet and began contracting. Observations showed that whenever the tissue moved, the electronic mesh emitted electrical signals corresponding precisely to that rhythm.