Slug the inspiration for glue that could do away with stitches

The Dusky Arion species of slug oozes a special kind of slime.

Slimy slug mucus has inspired a new glue which can stick to slippery surfaces in the body and could end the need for stitches.

For decades, scientists have attempted to invent an adhesive which can repair tears in bodily tissues, which are often covered in blood. Super-glue has been used for decades to close wounds, but it has never been able to help with internal injuries because it is too toxic to cells and will not stick to tissue.

Now researchers at Imperial College London and scientists in the US have created a super-strong glue which is as tough as cartilage, but which can cling to internal organs.

The design is based on slug mucus from the Dusky Arion species, which oozes a special kind of slime which prevents predators prying it from a surface. The slug slime is so effective because it contains positively charged proteins, which are attracted to the ground, or wall.

To create a similar mucus, the scientists made a water-based gel with positively charged molecules protruding from the surface, which create a static attraction with the negatively charged cells in the body.

"Nature has frequently already found elegant solutions to common problems," said Donald Ingber, Professor of Vascular Biology at Harvard Medical School.

The team tested their glue on dry and wet pig skin, cartilage, arteries, and tissue from the heart and liver, and found it bound to all of them.

The adhesive also maintained its bonding when implanted into rats for two weeks, or when used to seal a hole in a pig heart that was mechanically inflated and deflated and then subjected to tens of thousands of cycles of stretching. It also caused no tissue damage when applied to a liver haemorrhage in mice, which would usually be closed by stitches.

The team of researchers also included the Wyss Institute for Biologically Inspired Engineering and the John A. Paulson School of Engineering and Applied Sciences (SEAS).

It was was published in the journal Science.