Hydrogels have huge potential in the field of biomedicine, but aren't without their shortcomings in their existing form. These tiny polypeptide chains are championed for their many possible applications. Indeed, in the last few years alone we've seen advances that suggest they could find use in generating new heart tissue, fighting off superbugs and the controlled release of anti-inflammatory drugs. But researchers have now developed a hydrogel that mimics the elasticity of human tissue and can be activated by exposure to light, claiming it could offer safer means of repairing wounded tissue.

In order to bestow them with enough strength and stability, some hydrogels are treated with chemical compounds, which can then over time see them degrade into harmful materials. Bioengineers at Brigham and Women's Hospital (BHW) in Boston say they have overcome this problem by creating a hydrogel that becomes stronger only once it is exposed to light.

They call their new material a photocrosslinkable elastin-like polypeptide-based (ELP) hydrogel. As the gel is exposed to light, its molecules bind together to create a mechanical stability, so much so that it can endure more stretching than that experienced by arterial tissue in the body. Perhaps even more promising was the fact that they could dictate both the level of swelling and strength of the material, suggesting it could prove to have a number of uses.

"Our hydrogel has many applications: it could be used as a scaffold to grow cells or it can be incorporated with cells in a dish and then injected to stimulate tissue growth," says Nasim Annabi, PHD at BHW's Biomedical Engineering Division. "In addition, the material can be used as a sealant, sticking to the tissue at the site of injury and creating a barrier over a wound."

The gel was found to be consumed by naturally-occurring enzymes over time and had no toxic effects on living cells in the lab. The team also discovered that mixing the gel with silica nanoparticles gave it the ability to more effectively prevent bleeding, something that could allow better protection of a wound and stop bleeding with a single treatment.

The scientists say that more pre-clinical studies are required to test the gel's properties and safety before human trials will be possible.

The research was published in the journal Advanced Functional Materials.

View gallery - 2 images