Navy synthetically recreates fish slime that could be used to stop sharks and fires

Posted at 10:00 AM, Apr 25, 2017

PANAMA CITY, Fl. - A team of Navy scientists and engineers have managed to recreate a material used by marine life for defense that could be used by the Navy in everything from fighting fires to defending against sharks.

The team at the Naval Surface Warfare Center, Panama City Division has produced a synthetic component of hagfish slime from the alpha and gamma proteins of the Pacific hagfish.

The Pacific hagfish, sometimes known as a slime eel, is a bottom-dwelling scavenger. They produce slime for protection. That slime obstructs the gills of predators that come into contact with the slime.

Materials engineer Dr. Ryan Kincer says that slime has two components.

"The coiled up thread behaves like a spring and quickly unravels upon contact with water due to stored energy," said Kincer. "The mucin binds to water and constrains the flow between the micro channels created by the thread dispersion. The interaction between the thread, mucin, and seawater creates a three-dimensional, viscoelastic network. Over time, the thread begins to collapse on itself, causing the slime to slowly dissipate. Studies have shown the hagfish secretion can expand up to 10,000 times its initial volume."

Biochemist Dr. Josh Kogot says the slime thread has similar mechanical properties to kevlar, used for reinforcing rubber products and for protective gear.

In the future, the Navy could use the synthetically produced slime for fleet defense.

"The synthetic hagfish slime may be used for ballistics protection, firefighting, anti-fouling, diver protection, or anti-shark spray," said Kogot. "The possibilities are endless. Our goal is to produce a substance that can act as non-lethal and non-kinetic defense to protect the warfighter."

"Researchers have called the hagfish slime one of the most unique biomaterials known," added Kincer. "For the U.S. Navy to have its hands on it or a material that acts similar would be beneficial. From a tactical standpoint, it would be interesting to have a material that can change the properties of the water at dilute concentrations in a matter of seconds."

The team is now looking at different applications and variations of the synthetic slime.