An "injectable bandage" that uses nanoparticles and a gelling agent derived from seaweed could help stop internal bleeding and speed the healing of wounds.
Developed at Texas A&M University and detailed in the journal Acta Biomaterialia, the hydrogel compound represents another step forward in helping people recover from wounds that may be too deep for current medicine to treat, especially on the battlefield.
"Injectable hydrogels are promising materials for achieving hemostasis in case of internal injuries and bleeding, as these biomaterials can be introduced into a wound site using minimally invasive approaches," Akhilesh K. Gaharwar, assistant professor in the Department of Biomedical Engineering at Texas A&M, said in a university-issued statement.
When baking and medicine collide
The first ingredient in this bandage is kappa-carrageenan, a thickening agent derived from seaweed. You've almost certainly consumed carrageenan before, as it's commonly found in desserts, salad dressings and some sauces. Since it's made from seaweed, it's a vegan-friendly thickening agent, unlike gelatin, which comes from animal products. The second ingredient is 2-D clay-based nanoparticles called nanosilicates.
When the two ingredients are mixed together, the result is a hydrogel that has a 3-D polymer network similar to that of Jell-O, according to the university statement. (The researchers previously discovered that this unlikely duo worked well together in 2014.)
The injectable bandage is highly absorbent and generally stable. To understand why, imagine a cube of Jell-O. Inside that cube are flat circles, the nanoparticles or nanosilicates, which do much of the healing. The charged nature of these particles helps solve a number of medicinal needs. They increase protein absorption, increase platelet adhesion to the wounded area, thus reducing blood clotting time and enhancing cell adhesion. In addition, they basically function as a bandage to the wounded area, and the stable and slow-release nature of the hydrogel means that the nanosilicates deliver a "range of therapeutic biomacromolecules" that promote healing and tissue repair over a period of time.
"An ideal injectable bandage should solidify after injection in the wound area and promote a natural clotting cascade," Gaharwar said in the statement. "In addition, the injectable bandage should initiate wound healing response after achieving hemostasis."
Looks like they've gotten that bit taken care of. The researchers tested their hydrogel on samples of human and animal tissue in the lab and found that it initiated blood clotting in less than three minutes. Wound healing and tissue regeneration were also confirmed in the sample tests.
The hydrogel still needs to be tested on real human wounds, but researchers see the hydrogel as a way to quickly self-administer medical aid on the battlefield to prevent hemorrhaging and reduce fatalities due to excessive blood loss.