‘Squirtable’ elastic surgical glue seals wounds in 60 seconds

Scientists have developed a highly elastic and adhesive surgical glue that can be simply squirted on wounds to seal them within 60 seconds, doing away with the need for stitches. The glue, called MeTro, is ideal for sealing wounds in body tissues that continually expand and relax – such as lungs, hearts and arteries – that are otherwise at risk of re-opening.

The material, developed by researchers at University of Sydney in Australia and Harvard University in the US, also works on internal wounds that are often in hard-to-reach areas and have typically required staples or sutures due to surrounding body fluid hampering the effectiveness of other sealants.

MeTro sets in just 60 seconds once treated with UV light, and the technology has a built-in degrading enzyme which can be modified to determine how long the sealant lasts – from hours to months, in order to allow adequate time for the wound to heal. The liquid or gel-like material has quickly and successfully sealed incisions in the arteries and lungs of rodents and the lungs of pigs, without the need for sutures and staples.

MeTro combines the natural elastic protein technologies with light sensitive molecules. “The beauty of the MeTro formulation is that, as soon as it comes in contact with tissue surfaces, it solidifies into a gel-like phase without running away,” said Nasim Annabi, assistant professor at Northeastern University in the US. “We then further stabilise it by curing it on-site with a short light-mediated crosslinking treatment,” said Annabi, lead author of the study published in the journal Science Translational Medicine.

“This allows the sealant to be very accurately placed and to tightly bond and interlock with structures on the tissue surface,” he said. The process resembles that of silicone sealants used around bathroom and kitchen tiles. “When you watch MeTro, you can see it act like a liquid, filling the gaps and conforming to the shape of the wound,” said Anthony Weiss from University of Sydney.

“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,” Weiss said. “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.

“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,” said Ali Khademhosseini from Harvard Medical School. “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.