Hemorrhage—blood escaping profusely from a ruptured vessel—is a leading cause of potentially preventable death. Bandages often fail to stop the bleeding. But researchers say they have developed a better kind of dressing: one that repels blood and bacteria, promotes quick clotting and detaches without reopening the initial wound.

While developing blood-repelling coatings for medical devices, scientists at the National University of Singapore and the Swiss Federal Institute of Technology in Zurich found that one mixture of carbon nanofibers and silicone had an unexpected effect: it boosted blood clotting. So they sprayed the mixture onto conventional cotton gauze and applied heat to make it stick. In laboratory tests and experiments with rats, they observed that this new bandage promoted the production of fibrins, proteins that form a meshlike network at wound sites to aid clotting. The bandage also stayed dry, repelling blood, which made it easy to pull away from a wound—and an investigation using Escherichia coli showed that bacteria in a solution could not adhere to the material. The researchers described their findings last December in Nature Communications.

Study co-author Choon Hwai Yap, a biomedical engineer in Singapore, says more tests are needed to understand why the nanofibers encourage fibrin formation. But he notes that producing the material is inexpensive and could be replicated on a larger scale. “I think the new bandage can make a big difference in serious wounds, such as in a car accident or on the battlefield,” Yap says. “In these situations, you want to prevent bleeding very quickly by repelling it back into the wound, instead of soaking and draining blood from the body.”

Esko Kankuri, a pharmacologist at the University of Helsinki, who was not involved in the new study, cautions that human trials would be needed to prove the bandage's real capabilities. “This study presented the very first observation of the material's properties on blood and in very acute, uncomplicated wounds,” Kankuri says. “The results are very good and promising, but laboratory conditions are very far from actual clinical reality.”