Researchers at KAIST have created a spray-on powder that stops severe bleeding in about one second. The material forms a strong gel barrier on wounds and was designed with battlefield conditions in mind.
The powder, called AGCL, combines alginate, gellan gum and chitosan. When it contacts blood, it reacts with calcium ions to create a hydrogel in roughly one second. It can absorb more than seven times its weight in blood and achieves adhesive strength above 40 kPa.
Laboratory tests showed a hemolysis rate below 3 percent, cell viability above 99 percent and 99.9 percent antibacterial effect. Animal studies on liver injuries found reduced blood loss and normal liver function within two weeks, with no signs of toxicity.
The powder remained effective after two years of storage at room temperature and high humidity. PhD candidate Kyusoon Park, an Army Major, said the work began with a mission to save soldiers and expressed hope the technology will serve both defense and civilian medical needs.
The study, led by Park and Youngju Son under Professors Steve Park and Sangyong Jon, appeared online on October 28, 2025, in Advanced Functional Materials. It received the 2025 KAIST Q-Day President's Award and the Minister of National Defense Award in 2024.