ORGN 401 |
| The current rise in international concern over criminal terrorist attacks using chemical warfare (CW) agents has brought about the need for reliable and affordable detection of toxic gases. For example, in March 1995 the Aum Shinrikyo sect killed 12 and injured nearly 6000 people when sarin gas was released in a Tokyo subway. Therefore, there has been a significant interest in the decontamination, and detection of CW agents. There have been several approaches to the detection of CW agents. One approach utilizes chromogenic detector reagents, which directly bind to, or react with, a target nerve agent, causing a modulation in the absorbance spectra (i.e., a colorimetric response), fluorescence and chemiluminescence sensors have also been developed. There are also sensors that contain electrochemical moieties, which produce an electrochemical signal. Quartz crystal microbalance (QCM) is another sensing tool that can be utilized for the detection of toxic chemicals. The change in frequency of the quartz crystal is attributed to the change in mass of the quartz crystal (QC). It is well known that sulfur containing functional groups can act as “anchors” to gold surfaces to form self-assembled-monoayers. The work presented here describes the synthesis of a family of dithiol monomers that contain a reactive functional group, which will bind directly to the stimulant. These monomers then form SAMs onto a gold surface, on a QC platform. The same family of monomers have also been tethered to gold to form nanospheres. The synthesis and characterization of both the monomers, SAMs and the gold nanoparticles, and our initial results using QCM as a sensor towards chemical nerve agent stimulants, will be presented. |
|
Heterocycles and Aromatics, Molecular Recognition and Self Assembly
8:00 PM-10:00 PM, Tuesday, April 8, 2008 Morial Convention Center -- Hall A, Poster
Division of Organic Chemistry |