Whether it’s a machine, building, or aircraft, it’s always helpful to know whether a component is subject to mechanical stress. A new material uses integrated light-emitting algae to quickly and easily inform inspectors. The experimental substance, developed by scientists at the University of California, San Diego, is made primarily from seaweed-based polymers called alginates combined with living, single-celled algae called dinoflagellates. It also contains a polymer called poly(ethylene glycol) diacrylate to help it withstand heavy loads.
In the ocean, dinoflagellates produce flashes of light to deter predators. In small structures 3D printed with the new material, they also glow when the material is squeezed, stretched or twisted - the greater the mechanical stress, the brighter the light.
Importantly, mechanical stress sensors made from this material do not require any power supply or electronics. Still, dinoflagellates do require regular light and dark cycles in order to photosynthesize -- the energy gained from light is used to produce bioluminescence in the dark. So far, the 3D printed structures require little maintenance and can work for about five months under "harsh conditions."
Once further developed, it is conceivable that this material could also have applications in areas such as soft robotics or medical implants, which use light signals to release drug payloads or deliver treatments.
"The current work demonstrates a simple way to combine living and non-living components to create new materials that are self-sustaining and sensitive to fundamental mechanical stimuli found in nature," said Chenghai Li, a doctoral student in the laboratory of Professor Shengqiang Cai, the study's senior author.
A paper on the research was recently published in the journal Science Advances. In the video below, we can see a structure made of this material glow.