Health Desk—July 31, 2017: A defensive mucus secreted by slugs has inspired a new kind of adhesive that could transform medicine, say scientists.
The "bio-glue" is incredibly strong, moves with the body and crucially, sticks to wet surfaces.
The team at Harvard University have even used it to seal a hole in a pig's heart.
Experts have described the glue as "really cool" and said there would be "absolutely huge demand" for it.
Getting something to stick to a damp surface has been a huge challenge - think what happens when you get a plaster on your finger wet.
The university's Wyss Institute for Biologically Inspired Engineering turned to the "Dusky Arion" slug, which creates sticky mucus as a defence against predators.
"We engineered our material to take on the key features of slug mucus and the result is really positive," researcher Dr Jianyu Li said.
The bio-glue they produced has two components - the actual adhesive and a biochemical "shock absorber".
The incredible stickiness comes from the trinity of the attraction between the positively charged glue and negatively charged cells in the body; covalent bonds between atoms in the cell surface and the glue, and the way the glue physically penetrates tissue surfaces.
But it is the shock-absorbing component that is crucial - it takes the physical stress and strain, so the adhesive component stays stuck.
Experiments, published in the journal Science, show the glue is not toxic to living tissue and is three times stronger than any other medical adhesive.
Dr Li said, "I'm really amazed by this system. We have solved a big challenge and opened up big opportunities in the medical setting. The applications are pretty broad - the material is very tough, stretchy and compliant, which is very useful when you want to interface with a dynamic tissue like the heart or lungs."
It could be used as a patch on the skin or as a liquid injected into wounds deeper in the body.