Sandcastle Worm[/center]
An undersea worm has provided researchers with the recipe for a glue that surgeons could use to piece together shattered bones.
The sandcastle worm makes its tubular home by sticking bits of sand together. This is a remarkable feat considering the worm's glue works underwater and somehow "dries" after the worm applies it.
"Biology gave us a big new idea," said Russell Stewart, of the University of Utah in Salt Lake City, who led the research. "That worm had to solve a whole bunch of very complicated adhesion problems in order to glue things together underwater."
"If you wanted to glue bones together in open surgery, the problems are very similar to the problems that these marine organisms face in order to glue sand grains together," Stewart said, since both environments are wet.
Most bone repair is done with pins, plates and screws. However, when bone fragments are too small, these instruments can be cumbersome.
"There is a real medical need for good adhesives that work well but promote regeneration," said biomedical engineer Jennifer Elisseeff of Johns Hopkins University in Baltimore, who was not involved in the research. "I have doctors asking for it all the time."
"Going to nature is a nice approach," she continued. "Nature has taken a lot of time to evolve and develop these mechanisms."
The secret to the worm's success is combining two highly-charged proteins with charged ions. These components bind so tightly to one another that they make a separate fluid within the water, rather than dissolving and floating away.
The worm has also figured out how to get the glue to solidify at the right time underwater. After the proteins are released from the animal's adhesive ducts into the water, some shift in conditions -- likely a change in pH -- causes the glue to solidify within about 30 seconds.
The researchers have studied how the worm's cement works to design a synthetic version of the protein glue. The current version of the researchers' adhesive is approximately twice as strong as the sandcastle worm's glue. "We are working to increase the bond strength," Stewart said.
-http://dsc.discovery.com/news/2009/08/1 ... -glue.html
