A new glue inspired by slug slime can mend a broken heart. The adhesive sticks to wet surfaces, including the surface of a beating heart. It isn’t toxic to cells, which gives it an advantage over many surgical glues.
The slug-inspired glue is very stretchy and very tough, said Jianyu Li, a postdoctoral researcher at Harvard University’s Wyss Institute for Biologically Inspired Engineering. Li and his team applied the adhesive to a blood-soaked, beating pig heart and found that it worked better than any other surgical glue on the market.
The glue came from Arion subfuscus, a large and slimy species of slug found in North America and western Europe. These slugs excrete a sticky, yellow-orange slime that adheres well to wet surfaces.
The team mimicked this structure using artificial polymers layered onto what they called a dissipative matrix. The polymers provide the sticking power while the dissipative-matrix layer acts like a shock absorber. It can stretch and deform without rupturing.
To test the glue, the researchers applied it to pig skin, cartilage, arteries, liver tissue and hearts that were inflated with water or air and covered in blood. The material proved extremely stretchable, expanding 14 times its original length without ever breaking loose from the liver tissue. When used to patch a hole in a pig heart, the adhesive maintained its seal even when it stretched to twice its original length, at pressures exceeding normal human blood pressure.
The researchers even applied the adhesive to the beating heart of a real pig and found that the adhesion to the dancing, bloody surface about eight times as strong as the adhesion of any commercially available surgical glue.
The glue also tested on a living rat. They found that the new adhesive as good at stopping the blood flow as the standard glue. The rats treated with the new glue experienced no additional hemorrhaging up to two weeks after the surgery. The Surgiflo-treated rats, sometimes suffered from tissue death and scar tissue. The rats treated with the slime-inspired glue did not experience these side effects.
Whether the new glue makes it to the operating room depends on much more extensive clinical testing. But, the adhesive could make its debut as a new method of dressing external wounds on a shorter timeline.
More information: [Science]