KAIST's Spray-On Powder Stops Severe Bleeding in One Second

South Korean researchers have developed a spray-on powder that transforms into a hydrogel barrier on contact with blood, stopping life-threatening hemorrhaging in about one second — built for the battlefield, but poised to reshape emergency medicine everywhere.

A team at South Korea's KAIST has built a hemostatic powder that stops severe bleeding in roughly one second — the time it takes to spray it onto an open wound. The material, called AGCL powder, instantly transforms into a tough hydrogel barrier when it hits blood, sealing hemorrhaging wounds faster than any commercially available alternative.

The breakthrough comes from the labs of Professor Steve Park (Materials Science) and Professor Sangyong Jon (Biological Sciences), with a Korean Army Major — PhD candidate Kyusoon Park — directly embedded in the research team. His battlefield experience shaped the design constraints: the powder had to work instantly, survive two years of storage in humid heat, and conform to deep, irregular wounds that flat patch-style products cannot reach.

AGCL combines three naturally derived biocompatible ingredients — alginate, gellan gum, and chitosan. When sprayed into a bleeding wound, they react with calcium ions in the blood and gel in about one second. The powder absorbs 725% of its own weight in blood and achieves adhesive strength above 40kPa, enough to withstand firm hand pressure.

In animal trials, the powder outperformed commercial hemostatic agents: it reduced both blood loss and time-to-hemostasis in surgical liver injuries, with liver function returning to normal within two weeks. Lab tests showed a hemolysis rate below 3%, cell viability above 99%, and a 99.9% antibacterial effect. No systemic toxicity was observed.

Perhaps most striking for field deployment: the powder held its full performance for two years under room-temperature, high-humidity conditions — no refrigeration, no special handling. A single product works on deep, large, and uneven injuries alike.

Although built for combat medicine, the team sees civilian applications stretching from disaster response to surgery in medically underserved regions. The work earned both the 2025 KAIST Q-Day President's Award and the Minister of National Defense Award.

The study was published in Advanced Functional Materials.

Sources: KAIST via ScienceDaily, SciTechDaily