Scientists have once again turned to nature for inspiration; this time to create a synthetic version of hagfish slime as a way of stopping shark attacks as well as missiles. Currently being developed for the US Navy, this amazing substance is incredibly tough and expandable, just like its natural counterpart. Speaking about the project, Ryan Kincer, materials engineer at the Naval Surface Warfare Center, said:
Researchers have called the hagfish slime one of the most unique biomaterials known. For the US Navy to have its hands on it or a material that acts similar would be beneficial.
According to the team, this fascinating creature is a bottom-dwelling fish that is known primarily for the thick slime it ejects when faced with danger. Once deployed, the viscous substance blocks the gills and appendages of the underwater predator. In addition to being extremely tough, it is capable of expanding up to 10,000 times its normal size, as a result of contact with water.
As part of a new research, a team of scientists is trying to recreate an artificial version of this naturally-occurring slime, complete with all its wonderful properties. If developed, it could be used to keep sharks away from places frequented by humans, obstruct ballistics and fires from enemies, and finally protect divers. The hagfish slime, the group states, contains two protein-based components: a set of tightly-coiled threads and a membrane covering known as mucin.
At the time of danger, the organism excretes the slime, causing the threads to uncoil instantly. The mucin molecules combine with the water, as a result of which the connecting proteins between the individual threads are unraveled. This in turn allows the mucus to expand rapidly, engulfing the predator in an unshakeable trap. In case you are wondering, the slime’s strength is comparable to that of spider silk, and is nearly five times tougher than steel of the same weight.
The researchers genetically modified E. coli bacteria to produce the specific proteins needed to create the synthetic hagfish slime. The protein-based molecules were then brought together in a special solution. Using scanning electron microscope, the team was able to check the chemical similarity between the real and the lab-grown substances.
At present, the scientists are looking for ways to enhance the slime’s stability and expandability. Before it can be used by the US Navy, however, they have to figure out a way to deliver the material properly, such as with the help of a slime-shooting gun. Josh Kogot, a member of the team, added:
Our goal is to produce a substance that can act as non-lethal and non-kinetic defense to protect the warfighter. 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 synthetic hagfish slime may be used for ballistics protection, firefighting, anti-fouling, diver protection, or anti-shark spray. The possibilities are endless.
Source: The United States Navy