Scientists are developing a ‘smart glue’ that can bond securely underwater and may be turned on and off with electricity.
This glue could bind underwater sensors and devices to the hulls of ships and submarines and help unmanned vehicles dock along rocky coastlines or in remote locations.
It is made from an amino acid in mussel protein,dihydroxyphenylalanine (DOPA). Mussels attach to rocks,docks and ship hulls – a natural occurrence calledbiofouling.They do this by secreting a combination of naturalliquid superglues and stretchy fibers, called byssal threads, that works equally well in saltwater and freshwater.It can stick to both hard and soft surfaces and is strong enough to withstand the roughest sea conditions.
DOPA enables mussel secretions to be both cohesive and adhesive meaning they can adhere to themselves and other surfaces. Researchers blended DOPA with polymers like polyester and rubber to create the synthetic glue that holds together when wet.
Laboratory tests demonstrated this material can attach to a variety of surfaces,including metal, plastic and even flesh and bone.
There are possible medical applications, as it could lead to new kinds of bandages that will stay attached when someone sweats or gets wet, and make it less painful to remove a dressing. The smart glue might be used to attach prosthetic limbs and biometric sensors or seal surgical wounds.
Researchers are now trying to figure out how to use electrical currents to create a chemical ‘on-off’ switch that temporarily changes DOPA molecules to make the synthetic adhesive sticky or non-sticky at will.