'Injectable bandage' can heal internal injuries

Scientists, including one of Indian-origin, have developed an 'injectable bandage' - a therapeutic gel that can heal potentially fatal internal injuries.

A penetrating injury from shrapnel is a serious obstacle in overcoming battlefield wounds that can ultimately lead to death.

Given the high mortality rates due to hemorrhaging, there is an unmet need to quickly self-administer materials that prevent fatality due to excessive blood loss.

With a gelling agent commonly used in preparing pastries, researchers from the Texas A&M University in the US have successfully fabricated an injectable bandage to stop bleeding and promote wound healing.

Researchers used kappa-carrageenan and nanosilicates to form injectable hydrogels to promote hemostasis (the process to stop bleeding) and facilitate wound healing via a controlled release of therapeutics.

"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," said Akhilesh K Gaharwar, assistant professor at Texas A&M University.

"An ideal injectable bandage should solidify after injection in the wound area and promote a natural clotting cascade. In addition, the injectable bandage should initiate wound healing response after achieving hemostasis," said Gaharwar.

The study, published in the journal Acta Biomaterialia, uses a common thickening agent known as kappa-carrageenan, obtained from seaweed, to design injectable hydrogels.

Hydrogels are a 3D water swollen polymer network, similar to Jell-O, simulating the structure of human tissues.

When kappa-carrageenan is mixed with clay-based nanoparticles, injectable gelatin is obtained. The charged characteristics of clay-based nanoparticles provide hemostatic ability to the hydrogels.

Specifically, plasma protein and platelets form blood adsorption on the gel surface and trigger a blood clotting cascade.

"Interestingly, we also found that these injectable bandages can show a prolonged release of therapeutics that can be used to heal the wound" said Giriraj Lokhande, a graduate student in Gaharwar's lab.

"The negative surface charge of nanoparticles enabled electrostatic interactions with therapeutics thus resulting in the slow release of therapeutics," said Lokhande.