Barnacle-inspired medical glue halts bleeding

The paste was inspired by barnacles, which use their cement glands to adhere to rocks, ships and larger animals and remain stubbornly in place despite being affixed to often contaminated, wet conditions and variable surfaces. They are able to do this due to the production of a type of oil matrix which cleans the surface and repels moisture, which is followed by production of a protein which cross-links them with the molecules of the surface.

This two-step process was replicated in the quick-acting medical glue, which functions well in challenging sites covered with blood or other bodily fluids.

Surgeons historically use a type of material to speed up coagulation and form a clot to halt bleeding, which takes several minutes at best. However, this paste can halt bleeding in as little as 15 seconds, even before clotting has begun.

The paste is made of an injectable material, consisting of a water-repelling (and blood-repelling) oil matrix containing bio-adhesive microparticles. These microparticles covalently crosslink to each other and the surface of the tissue with gentle pressure after the oil has provided a clean place to connect. Over a period of weeks, the material is slowly resorbed.

The study – which used pig aortas and heart and liver tissues in rats and pigs – demonstrated that the glue can sustain large amounts of pressure; forms strong interfaces with bloody tissue, and outperforms conventional haemostatic materials. The paste may aid the treatment of severe bleeding even for patients with bleeding disorders, the researchers reported in Nature Biomedical Engineering.

“Our data show how the paste achieves rapid haemostasis in a coagulation-independent fashion. The resulting tissue seal can withstand even high arterial pressures," says Dr Christoph Nabzdyk, a lead author of the study and a cardiac anaesthesiologist and critical care clinician at the Mayo Clinic. “We think the paste may be useful in stemming severe bleeding, including in internal organs and in patients with clotting disorders or on blood thinners. This might become useful for the care of military and civilian trauma victims.”

In 2017, Harvard researchers reported the development of a new type of surgical adhesive for use in bloody conditions; their adhesive, which can stretch and adjust to moving parts, was inspired by slug slime.