Grant: Strategic Projects - Group

The detection of small amounts of explosive materials is an important issue from the viewpoint of nationalsecurity and forensic science. Various methods for explosives detection have been developed. Unfortunately,the most sensitive of them are relatively slow and require instrumentation which is too complex and expensivefor use in the field. One should also note that for the purpose of reducing the number of the false alarms, itwould be beneficial to introduce systems with several "orthogonal" (i.e. utilizing different physical, chemical orbiological principles) detection technologies. Thus, there is an apparent need to continue developing newmethods of explosives detection, with the final goal of making them faster, less expensive, more sensitive andmore reliable.We propose exploring two interrelated approaches for the development of explosives' sensors. In the firstapproach, natural photosynthetic reaction centers are employed; in the second approach we will utilize theartificial mimics of these reaction centers. Both approaches are based on explosives affecting the electrontransfer processes in the complexes incorporated into electrical circuits. While high-resolution optical /spectroscopic methods (including those at low temperatures) will be used to determine the details ofexplosives/sensor interactions and to optimize the design of the sensors, the final detection scheme that will beelectrochemical in nature, will operate at room temperature and will not rely on complex instrumentation.The implementation of such sensors by the supporting organizations and their partners promises botheconomical and safety-related benefits to Canada and its allies.The project is inspired by recent progress in the development of inexpensive and sensitive herbicide biosensorsbased on photosynthetic reaction centers, and by the fact that the chemical structure and properties of nitricexplosives are similar to those of herbicides detectable by such biosensors.