A nanoscale biological coating could prevent battlefield deaths by halting bleeding nearly instantaneously. Developed by engineers at MIT with the assistance of Ferrosan Medical Devices A/S (Soeborg, Denmark), the coating includes thrombin, a protein involved in blood clotting that has been used clinically for decades for topical hemostasis and wound management. The coating also contains tannic acid, a molecule found in tea.
In a recent study, the researchers developed a biological coating consisting of two alternating layers sprayed onto a material, such as a sponge. The coating forms a film containing a high level of functional thrombin. According to the researchers, sponges coated with the material can be stored stably and carried by soldiers or medical personnel to treat the wounded. Similar sponges could also prove useful in civilian hospitals.
From the announcement:
Once sprayed, the sponges can be stored for months before use. The sponges can also be molded to fit the shape of any wound. “Now we have an alternative that could be used without applying a large amount of pressure and can conform to a variety of wounds, because the sponges are so malleable,” [researcher Anita] Shukla, PhD, says.
In tests with animals at Ferrosan, the coated sponges were applied to wounds, with light pressure (from a human thumb), for 60 seconds — and stopped the bleeding within that time. Sponges lacking thrombin required at least 150 seconds to stop the bleeding. A simple gauze patch, applied for 12 minutes (the length of the experiment), did not stop the bleeding.
The researchers are now working to develop a sponge that could be used for both blood-clotting and antibiotic applications.
MIT announcement: New way to stop the bleeding
Abstract in Advanced Materials: Hemostatic Multilayer Coatings
Image: The coating is comprised of thrombin (shown above) and tannic acid. Courtesy of Wikimedia/Nevit Dilmen.