A Novel Device for Surface-Enhanced Detection of Chemical and Biological Warfare Agents

Onsite detection of potentially harmful chemical and biological warfare agents (CBWAs) in a timely manner is critical to the defense and safety of personnel and material assets. However, currently available methods for biological agent detection rely on fragile biomolecules for target recognition, require sample preparation, and well equipped laboratory for further analysis. A variety of detection technologies currently available for detection of chemical agents, field-deployable systems such as the M21 passive IR standoff detector and the CAM/ICAM ion mobility detector are prone to false alarms due to the presence of interfering species. Spectroscopic techniques like surface enhanced Raman spectroscopy (SERS) can detect trace levels of analytes adsorbed on metal nanoparticles. However, such metal nanoparticles are neither optically stable nor selective. Hence, a combination SERS and selectivity offered by selected molecular monolayers to allow selective binding of target analytes presents an extremely versatile method to unequivocally identify a wide range of CBWA. The aim of this Phase I research project is to demonstrate feasibility of use of stable Raman signal enhancing surfaces modified with selected monolayers for rapid detection of CBWAs by SERS using surrogate agents, and to build a breadboard system equipped with an air sampler.