Likewise, most agree that these incredibly small materials can behave quite differently from conventional materials. Nonetheless, neighborhood stores feature products that promise benefits from these near-atomic level materials, from paints and cosmetics to toothpaste and sunscreens. But, could we be putting human health at risk by exposing consumers to potentially toxic materials?

To investigate the damage potential of sub-micron sized particles, S.K. Sundaram and Thomas J. Weber, scientists at the Department of Energy's Pacific Northwest National Laboratory in Richland, Wash., have harnessed living cells to monitor responses to a variety of biologically active test agents. They presented their findings Friday at the American Association for the Advancement of Science annual meeting.

"Our process requires that live cells be grown on an infrared transparent substrate giving us an opportunity to closely examine the biological effects in living cells," said Sundaram. Live cell Fourier transform infrared, FTIR, spectroscopy offers several attractive features for these investigations. These include the potential to detect biologically active nanoparticles without any prior knowledge of cell signaling pathways affected by them or need of a contrast agent to detect the biological response. Thus, live cell FTIR spectroscopy is expected to be a sentinel of exposure to help identify the physico-chemico properties of nanoparticles that mediate biological activity, without bias of what that biological activity represents.

The PNNL scientists are also developing infrared transparent chemistries that are expected to improve FTIR measurements in live cell experiments. "We believe this report outlines the first use of FTIR spectroscopy to exa
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Contact: Geoffrey Harvey
geoffrey.harvey@pnl.gov
509-372-6083
DOE/Pacific Northwest National Laboratory
17-Feb-2006