A nanoscale biological coating that can halt bleeding nearly instantaneously

MIT engineers have developed a nanoscale biological coating that can halt bleeding nearly instantaneously, an advance that could dramatically improve survival rates for soldiers injured in battle.
 

The researchers, led by Paula Hammond and funded by MIT’s Institute of Soldier Nanotechnologies and a Denmark-based company, Ferrosan Medical Devices A/S, created a spray coating that includes thrombin, a clotting agent found in blood. Sponges coated with this material can be stored stably and easily carried by soldiers or medical personnel. The sponges could also prove valuable in civilian hospitals, says Hammond, the David H. Koch Professor in Engineering.
 
Spray layer-by-layer assembly is used to create hemostatic films containing thrombin and tannic acid. The spray assembly technique enables coating of porous and absorbent commercial gelatin sponges with these films. Coated sponges are able to promote instantaneous hemostasis in a porcine spleen bleeding model.
 
Uncontrolled bleeding is the leading cause of trauma death on the battlefield. Traditional methods to halt bleeding, such as tourniquets, are not suitable for the neck and many other parts of the body. In recent years, researchers have tried alternative approaches, all of which have some disadvantages. Fibrin dressings and glues have a short shelf life and can cause an adverse immune response, and zeolite powders are difficult to apply under windy conditions and can cause severe burns. Another option is bandages made of chitosan, a derivative of the primary structural material of shellfish exoskeletons. Those bandages have had some success but can be difficult to mold to fit complex wounds