While the common house spider may be creepy, it also has been inspiring researchers to find new and better ways to develop adhesives for human applications, such as wound healing and industrial-strength tape. Think about an adhesive suture strong enough to heal a fractured shoulder and that same adhesive designed with a light tackiness ideal for "ouch-free" bandages.
University of Akron polymer scientists and biologists have discovered that this house spider — in order to more efficiently capture different types of prey — performs an uncommon feat. It tailors one glue to demonstrate two adhesive strengths: firm and weak. Released today by Nature Communications, a study by the UA scientists shows that cobweb spiders use adhesive discs to anchor webs to ceilings, walls and various other surfaces. While they use the same glue on all surfaces, they create it using two different designs to give it a strong or weak grip, depending on whether its prey is flying or crawling on the ground.

The researchers who made the finding are already working toward developing a synthetic adhesive that mimics this intelligent design strategy employed by the house spider. The super sticky adhesive disc that anchors webs to ceilings and vertical surfaces keeps cobwebs mounted in place when struck by airborne insects flying at high velocities. On the contrary, the adhesive disc that attaches webs to the ground to capture walking insects does so with a weak grip. When a walking insect encounters the web, the weak adhesive disc snaps away from the ground and leaves prey suspended in the air by a silk thread.

The strong adhesive attachment that holds the strand of threads that the fast-moving Spiderman uses to spring to a building doesn’t lose its grip. Likewise, cobweb spiders use a "staple-pin" adhesive disc to keep their webs' dragline silk threads attached firmly to ceilings and walls. Conversely, the "dendritic" adhesive discs that mount gumfoot silk threads to the ground do so with a loose grip.

"What we have also discovered is a key design principle," the researcher says. "It's not a question of the inherent chemistry of the glue, but how the same glue can have different degrees of adhesion."

They say the design principles could result in the development of synthetic adhesives, particularly for biomedical applications.

This story is reprinted from material from The University of Akron, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.