Logan • The United States Navy thinks spiders' webs may hold the secret to anchoring objects under wet conditions and has funded two years of research at Utah State University to seek the answer.
"There are a number of spiders that live near streams and in rainforests and in areas that get very wet," said Randy Lewis, who heads spider silk research at the university. "The adhesive webs seem to be relatively unaffected by water."
Navy officials want to know if the adhesive variety of spider silk, which arachnids use to anchor their webs, could be manufactured and used effectively as an underwater adhesive. The type of silk is known as piriform, tiny fibers of attachment cement spiders use to safely anchor their draglines and to glue joints of a web together.
"Piriform has chemical and physical properties that enable it to attach to virtually any surface, even when wet, yet it's less than a micron in diameter," Lewis said.
Little is known about piriform's mechanical properties, Lewis said.
"The Navy envisions a kind of super, one-sided Velcro-type fastener that would attach to surfaces underwater," he said. "Spiders successfully attach webs to rocks, trees and other surfaces right next to water in very humid environments. We're trying to see if we can produce this material synthetically, test its adhesive properties and duplicate its function."
Lewis' work involves reproducing silks using a variety of different systems that include bacteria, alfalfa and silkworms. He may be best known for his research with genetically modified "spider goats," which produce a substance in their milk that can be extracted to manufacture web fibers.
"Spider silk has properties unmatched by any man-made material," Lewis said. "We're trying to reproduce nature's ancient biomaterial."
Most of Lewis' other research focuses on a type of web spiders use when strength is the main goal. The USU lab hopes to improve the efficiency of synthetic spider silk production for such future biomedical applications as synthetic ligaments, tendons, skin, bone and as ultra-fine sutures for delicate surgeries, such as facial reconstruction.
The Office of Naval Research grant is about $173,000. A recent National Science Foundation Partnerships in Innovation Award was about $596,000 and allows Lewis to work with several commercial companies. A recent NSF grant for collaborative research with the University of Nebraska-Lincoln was about $381,000. In total, the new funding is $1.15 million.
With the newest funding, the Lewis Lab, part of USU's Synthetic Biomanufacturing Institute, will support more than 25 graduate and undergraduate students, as well as four postdoctoral scientists, in research endeavors.
"This project will involve almost exclusively graduate and undergraduate students," Lewis said. "It will be student-conducted and student-driven research."
Lewis said that, basically, tests will involve manufacturing piriform disks and tapes to press against other surfaces. The amount of force required to pull the objects apart will be measured and will reveal the piriform's strength and characteristics as a fastening agent.
"From our perspective, we're happy to see the Navy's support, especially with sequestration, with the rate of funding for new grants very low," Lewis said. "It's a vote of confidence for our ideas that the Navy thinks this may turn out to be something very useful."