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Kevin Kit Parker wants to build a human heart. His young daughter loves the New England Aquarium in Boston. In this Science report, father’s and daughter’s obsessions have combined in an unlikely creation: a nickel-sized artificial stingray whose swimming is guided by light and powered by rat heart muscle cells.
Incorporating advances in engineering, cell culture, genetics, and biomechanics, the “living” robot is “clearly a technical tour de force,” says Adam Summers, an integrative biologist at the University of Washington, Seattle. And some think that by melding cells and artificial materials into a pulsating structure, the device brings Parker’s dream of engineering a human heart a step closer. “One can imagine that one day we can use this technology to rebuild parts of the human body,” says Kedi Xu, a neural engineer at Zhejiang University in Hangzhou, China.