Karen Brewer, professor of chemistry, will give an invited talk, and her students will present a number of posters at the American Chemical Society (ACS) 230th annual meeting in Washington, D.C., Aug. 28 through Sept. 1 to explain their discoveries and applications.
Many scientists are racing to create ways to deliver cancer-killing drugs to tumors without harming surrounding tissue. At ACS meetings in August 2004 and March 2005, Brewer and her team announced the creation of molecular assemblies that solved two challenges facing photodynamic therapy, or activating drug delivery devices with light. The Brewer group's systems could be activated by visible light in the therapeutic range - a wavelength not blocked or reflected by tissue. The systems also were able to operate without oxygen.
The group now has more kinds of supramolecular assemblies that absorb therapeutic light and they are adding units to the structure. For instance, they added platinum, a metal with anticancer activity because it binds to DNA inhibiting cell replication. "Using platinum assures that we are activating complexes that are already attached to the target," Brewer said. "The previous systems had an association with DNA but could release, which might result in an impact on other parts of the cell."
Because the therapeutic complexes only activate with visible light, the researchers are now able to add a luminescent tag that glows in the presence of ultra violet (UV) light. "The UV light does not activat