Sticky Sponge That Works Even When Blood Won’t Clot

Scientists have created a new type of sponge that sticks strongly to wet tissue and stops bleeding even when patients take blood‑thinning drugs. The trick is coating one side of a gelatin sponge with a special polymer called PANS, which contains NHS ester groups. These groups form strong bonds—both covalent and hydrogen—to blood proteins, the sponge itself, and surrounding tissue. Because PANS can pull the sponge tightly against wet surfaces, it achieves a lap‑shear strength of about 114 kPa. That means the sponge stays put during surgery and can absorb blood quickly thanks to its preserved pore structure.In laboratory tests on rats, the sponge cut a liver or damaged an artery and stopped bleeding faster than standard commercial sponges. The effect was seen whether the animals were on normal blood‑clotting or had been given heparin, a common anticoagulant. The material also shows low toxicity to cells and does not cause excessive blood cell destruction or inflammation when examined under a microscope. Overall, the design offers a way to control bleeding that does not rely on the body’s usual clotting process. It could help surgeons treat internal injuries in patients who cannot rely on normal blood coagulation, such as those on anticoagulants or injured in combat situations.