Forget stitches or staples. A new type of surgical glue can do what those cannot -- create a truly complete seal. This innovative tool comes from a collaboration between researchers from the United States and Australia who ultimately want to use the glue in emergency situations. 

The glue is called MeTro and it's tailored to be used on wounds that risk reopening due to constantly expanding and contraction. The researchers noted that it would even work on internal tissues including heart and lung. 

"A good surgical sealant needs to have a combination of characteristics: it needs to be elastic, adhesive, non-toxic and biocompatible," said lead author Nasim Annabi, Ph.D. "Most sealants on the market possess one or two of these characteristics, but not all of them. We set out to engineer a material that could have all of these properties."

In order to create MeTro, the team engineered a unique form of sealant using natural elastic proteins. These proteins were inspired by tropoelastin -- the protein that allows human body tissue to resume shape after contracting or stretching. After applying the sealant to a wound, the team used a stream of UV light to set the material. The process only took 60 seconds to set. 

MeTro also has a built-in degrading enzyme that can be tailored to the injury's severity. The researchers drew similarities to it and sealants around bathroom tiling. It's this enzyme that helps separate the glue from other 'wound hacks' like using superglue on cuts. Also, this glue is made for wounds significantly larger (and internal) than what the Mayo Clinic says superglue can fix. 

"When you watch MeTro, you can see it act like a liquid, filling the gaps and conforming to the shape of the wound," said study co-author Anthony Weiss in a statement. "It responds well biologically, and interfaces closely with human tissue to promote healing. The gel is easily stored and can be squirted directly onto a wound or cavity."

The researchers tested MeTro to seal cuts in the arteries and lungs of rodents. They also used the glue in the lungs of pigs. The glue worked without the need for additional closures in all cases.

Professor Ali Khademhosseini with Harvard Medical School said the sealant goes above and beyond traditional expectations for similar medical glues. 

"MeTro seems to remain stable over the period that wounds need to heal in demanding mechanical conditions and later it degrades without any signs of toxicity; it checks off all the boxes of a highly versatile and efficient surgical sealant with potential also beyond pulmonary and vascular suture and staple-less applications," he said.

Weiss noted that this success could have a number of life-saving applications.

"The potential applications are powerful -- from treating serious internal wounds at emergency sites such as following car accidents and in war zones, as well as improving hospital surgeries," he said. 

The next step for the researchers includes taking MeTro to clinical testing. The full study can be found in the journal Science Translational Medicine. 

Source - https://interestingengineering.com/new-fast-sealing-surgical-glue-closes-wounds-in-a-minute