Researchers at MIT and Harvard University have developed tiny gold-studded scaffolds that can be used to build tissue in which cells have a synchronous beat, a possible repair tool for treating heart-attack victims.
In a study reported in Nature Nanotechnology, Daniel Kohane, a professor in the Harvard-MIT Division of Health Sciences and Technology (HST), and colleagues improved the electrical conductivity of scaffolds used to grow cardiac cells.
They devised a new scaffold material but based it on alginate, an organic substance that's already used in tissue scaffolds. They combined the alginate with a solution containing gold nanowires, which are good conductors.
After cardiac cells were seeded on the composite scaffold, the researchers compared the conductivity of the gold-enhanced cells with cells grown on regular alginate. They checked each for the presence of calcium, which helps electrical signals travel in the tissue.
In the vid below, calcium-labeled cells glow green. The gold-enhanced scaffold cells, pulsing together, showed a signal range enhanced by three orders of magnitude.
"Tissues grown on these composite matrices were thicker and better aligned than those grown on pristine alginate," the researchers wrote, "and when electrically stimulated, the cells in these tissues contracted synchronously."
Conduction was improved to a scale of many millimeters compared with a few hundred micrometers with regular alginate and several centimeters in normal heart tissue.
"It's really night and day. The performance that the scaffolds have with these nanomaterials is just much, much better," MIT quoted Kohane as saying.
The researchers plan to test the scaffolds in vivo next in the hopes of producing better heart patches, though the technology might also be used for muscle or nerve cells.