Using stitches to bind skin together seems so primitive. Why not use a special slug glue that sticks to skin? Biologists working on that medical technology now think they could make surgical sutures and staples relics from the past.
A number of scientists are currently studying the different kinds of natural adhesives produced by mussels, snails, worms, insects and other living things. Ithaca College biology professor Andrew Smith and his students are carefully collecting slug secretions in an effort to create an effective adhesive derived from it.
Slugs secrete special gels that help them move across a surface. “Gel like this would make an ideal medical adhesive,” Smith told the college. “It would stick to wet surfaces and no matter how much the tissue flexed and bent, the gel would flex and bend with it. There would be no leakage or scarring.”
Surgical staples and sutures are the norm because they can keep bodily fluids put, but these measures can also fail by popping or coming undone. Gluing skin together sounds like it would work better, but the right adhesive needs to stick to wet surfaces and also hold fluids back effectively.
Plucking unsuspecting slugs from their natural environment before they can secrete all their goo in defense, Smith and his students have been able to gather tiny gel samples from slugs in the lab. Studying the substance, he found it to be a dilute, tangled network of polymers held together with zinc, calcium, iron and copper ions.
The hunt for nature-inspired adhesives stretches much farther than slug trails. In Germany researchers are taking a closer look at the asparagus beetle, which attaches its eggs to the vegetable using one of the world’s strongest natural glues. Over at the University of Utah, bioengineering professor Russell Stewart is studying biomimetic underwater adhesives and natural bio-adhesives produced by caddisflies that can spin silk underwater.
Back at Ithaca College, Smith and his colleagues haven’t made a slug-based adhesive to test yet but they’re working on it. After the scientists collected the secretion samples, they froze the substance for future analysis and returned the slugs to the outdoor trails where they originally found them. Hopefully we’ll advance faster with this substance than they do.
Credit: Nigel Cattlin/Visuals Unlimited/Corbis