High-performance orthogonal sensing system and data analysis algorithm for trace explosives detection

A hybrid sensor system is developed for trace explosives detection. The system incorporates orthogonal operational principles of its subcomponents: Surface Enhanced Raman Spectroscopy (SERS) provides high sensitivity as well as high selectivity, i.e., ultra-low detection limits simultaneously with very low false alarm rates while an ionization-based method, such as Ion Mobility Spectrometry (IMS), is used as a pre-filter to SERS, for this approach. This solution offers a significantly improved detection technology when both modes are evaluated concurrently, especially making a significant enhancement of the capability of SERS for open environment applications. This concept of operation provides a clean and controlled environment, and it enhances the operational reliability of SERS which forms the critical unit for this new detection system. The combined system outperforms the individual IMS or SERS components taken individually. This hybrid, orthogonal sensing method can be applied to other types of threat detection as well, namely, chemical and biological threats.