Department of Chemistry faculty researchers have been awarded two different multi-million dollar grants from a U.S. Department of Defense agency for the exploration of new technologies that could be used to detect and destroy chemical warfare agents, toxic industrial chemicals and nerve gas.
Each award is a three-year, $1.5 million grant from the Defense Threat Reduction Agency's (DTRA) Joint Science and Technology Office. Each grant could be extended another two years and funded an additional $1 million.
Professor Eric Borguet is collaborating with a team of researchers from the University of Pittsburgh to develop more economical methods to sense and eliminate weapons of mass destruction. The researchers are investigating the use of what are called multifunctional, metal-organic frameworks (MOFs) with plasmonic cores comprised of metal nanoparticles.
When light is shined on such plasmonic materials, electrons are excited. These excited electrons can then be used to detect specific, targeted chemicals and create chemical reactions that render them harmless.
Currently, 99 percent of the plasmonic materials that have been studied for such purposes are comprised of either gold or silver. The Pitt-Temple team's goal is to develop new plasmonic materials from cheaper, more earth-abundant metals and metal combinations.
"We're interested in detecting and ultimately destroying both chemical warfare agents and chemicals with industrial applications that, because of their toxicity, could also be used as chemical warfare agents," says Borguet. "If we are successful in identifying more abundant metallic materials, it could impact not only chemical warfare agents but also other plasmonic applications."
For the Temple team, Borguet is directing the sensing and catalytic studies, deploying a suite of techniques to help optimize the response of the materials to specific target chemicals.
Borguet's collaborators at the University of Pittsburgh include the study's principal investigator, J. Karl Johnson, professor of chemical and petroleum engineering; Nathaniel Rosi, professor of chemistry; and Jill Millstone, associate professor of chemistry.
Meanwhile, a Temple-led team that includes two Department of Chemistry professors and researchers from UCLA and the Army Medical Research Institute of Chemical Defense (AMRICD) is exploring a new technology that has the potential to convert highly toxic organophosphate nerve agents into harmless phosphates.
Currently, it is possible for certain enzymes—when combined with water in the process known as hydrolysis—to accelerate the breakdown of organophosphorus nerve agents. But the research project's principal investigator, Professor Christian Schafmeister, notes that the effectiveness of such enzymes varies widely depending on such variables as shifting temperature or solvent conditions.
As an alternative, Schafmeister's team plans to synthesize complex, shape-programmable macromolecules that are called "spiroligomers" or "Molecule Lego." These macromolecules would have caves or crevices containing metals that, in combination with water, would be able to bind organophosphorus nerve agents and greatly speed up their breakdown into harmless compounds.
These spiroligomers are much more robust and stable than enzymes and—because they are metal-based—also would not generate immune responses in humans.
"For all these reasons," says Schafmeister, "they would have the potential to decontaminate large surface areas. They might also be used as therapeutic drugs and countermeasures to treat warfighters exposed in the field to nerve gas.
"In addition, they could be used as nerve gas sensors."
Schafmeister's research collaborators include Associate Professor Michael Zdilla; Kendall N. Houk, the Saul Winstein Chair in Organic Chemistry at the University of California, Los Angeles; and Shane Kasten, a research physical scientist with the AMRICD in Aberdeen, Maryland.