The jellyfish made out of rat hearts and silicone!

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In what could be the oddest experiment I've stumbled across this year, reports are in of a remarkable creation at the California Institute of Technology, says Nathan Hill.


Not a jellyfish in the classic definition, researchers have created a medusa out of the inert chemical silicone, inlaid with the individual cells of rat hearts. The result, when placed into a solution and exposed to electrical charge, is a replicant, emulating the muscular action you’d see from any self-respecting jellyfish (scroll down for video).

The first question many people will have about a man made pseudo-jelly will be 'why bother?' Doctoral student Janna Nawroth explains that "A big goal of our study was to advance tissue engineering." She goes on to say that the idea "was that we would make jellyfish functions – swimming and creating feeding currents — as our target and then build a structure based on that information."

The real ramifications of the research are the potential inroads to human medicine, and given that the pulsing, rhythmic pumping of jellyfish is close to the action of the human heart, there are long-term implications for human care on the back of discoveries.

To make the cyber jelly, a silicone polymer was shaped into a thin membrane, until it resembled a young jellyfish with eight arms (jellyfish fans will know this as the ephyrae stage). The second stage involved printing a protein pattern on to this silicone frame, the idea being that the proteins act as a guiding scaffold for the growth of individual heart muscle cells from rats.

Once complete, the construct was placed into a container of electrically conducting fluid, and then subject to oscillating voltages. The result was the contraction of muscles that emulated the movements of real jellyfish. As a bonus, it transpires that the muscles even started to twitch before the current was applied.

The next stage of research hopes to create a self contained version that is able to sense and activate itself, using its own cues, making it more akin to a human heart model. The team also express an interest in creating a version of the medusa that is able to gather its own food source. Admittedly, that would be a pretty impressive piece of bio-inspired engineering.

You can watch a video showing how it compares to the real thing below: