MIT researchers have developed a coating of thrombin and tannic acid. After being sprayed onto a surface, the material can halt bleeding within seconds.

Researchers from the Massachusetts Institute of Technology in the U.S. have created a nanoscale biological coating that can halt bleeding within a few seconds.

The spray contains thrombin, a clotting agent found in blood and tannic acid, a small molecule found in natural tea. The spray was tested on a sponge and could be stored for several months before use.

This is very useful for soldiers as it can be easily carried, stored and used in the battle arena as it has a very long shelf life.

Uncontrolled bleeding is the main cause of death in the battlefield. Earlier, the army personnel used tourniquets, a cuff-like material used to stop bleeding, but that was not very effective. Though fibrin dressings and glues are much effective, they have a very short shelf life.

According to the researchers, this spray is not only useful for soldiers but also for the general public, as it can be easily carried anywhere.

"The ability to easily package the blood-clotting agent in this sponge system is very appealing because you can pack them, store them and then pull them out rapidly," says Paula Hammond, who led the research team.

"A key advantage of the spray method is that it allows a large amount of thrombin to be packed into the sponges, coating even the interior fibers," says David King, instructor in surgery at Massachusetts General Hospital.

"All of the existing hemostatic materials suffer from the same limitation, which is being able to deliver a dense enough package of hemostatic material to the bleeding site. That's why this new material is exciting," he said.