Fate, who retired in 2010, views the debilitating effect of rising health care costs on the nation's economy as a national security issue.
"To me it seems like such a logical match, the best engineering lab in the country working with the best medical research institution in the country to solve some of these big problems that are nearly driving this country bankrupt," he said.
After Sandia researchers came up with interface materials, MD Anderson surgeons sutured the scaffolds into legs of rats between a transected peroneal nerve. After three to four weeks, the interfaces were evaluated.
Samples fabricated from PBF turned out to be too thick and not porous enough for good nerve penetration through the scaffold, Dirk said. PDMS was more promising, with histology showing the nerve cells beginning to penetrate the scaffold. The thickness of the electrospun mats, about 100 microns, were appropriate, Dirk said, but weren't porous enough and the pore pattern wasn't controlled.
The team's search for a different technique to create the porous substrates led to projection microstereolithography, developed at the University of Illinois Urbana-Champaign as an inexpensive classroom outreach tool. It couples a computer with a PowerPoint image to a projector whose lens is focused on a mirror that reflects into a beaker containing a solution.
Using a laptop and a projector, Dirk said the researchers initially tried using a mirror and a 3X magnifying glass, but abandoned that because it produced too much distortion. They now use the magnifying glass to focus UV light onto the PDMS-coated silicon wafer to form thin porous membranes.
While the lithography technique is not new, "we developed new materials that can be used as biocompatible photo crosslinkable polyme
|Contact: Sue Holmes|
DOE/Sandia National Laboratories