Sept 7 : Researchers at Harvard University have created thin sheets of elastic film studded with rat heart muscle and zapped them with electricity, allowing them to contract, bend and move.

The findings could point the way to sophisticated new “soft robots”, effective replacement organs, and better prosthetic devices, said biomedical engineer Kit Parker.

Parker said the electricity coaxes the muscle cells to contract, bend and flex the polymer sheets.

Parker said the researchers stamped their elastic films with a pattern of stripes made of a protein called fibronectin. The scientists were successful in making the heart muscle cells grow along these paths, he said.

“If you put down a pattern, you automatically get a tissue. The cells arrange themselves into working muscle fibres,” said Parker.

Parker said, while sometimes the movement continued spontaneously; at other times, it proceeded only in tandem with the electrical inputs.

By cutting out triangles, rectangular strips, and other shapes of this material, the scientists were able to make living origami that could swim, grab, and crawl.

Triangular sheets of the material behaved like zebrafish, which swim by swinging their tailfin to one side and then straightening their tail and coasting.

Parker said the team also created a crawling mini-machine with a rounded body and a “leg” at the back that flexed to push the device along.

Study co-author Adam Feinberg said the team made a spontaneously coiling strip as well as a clawlike gripper that could grab tightly enough to move individual cells.

Parker said their “greatest accomplishment was not that they made these walking devices”.

“Rather, the achievement has been that the team was able to get the muscle cells – and the molecular motors inside them – to line up properly. In order to have rhythmic contraction, you need to have proper alignment of the muscle cells. To date, that is what has vexed tissue engineers,” he said.

The research appears in this week’s issue of the journal Science. (ANI)