Sensing explosives with suspended core fibers: Identification and quantification using Raman spectroscopy

Abstract

This works demonstrates the use of suspended core optical fibers as a platform for explosives detection in solution using Raman spectroscopy. This architecture combines small sampling volumes with long light-analyte interaction lengths, resulting in identification of minute quantities of explosives in solutions. In addition, the Raman signature of the solvent is used as an internal calibration standard to allow quantification of the detected molecule. Our results show detection of sub-microgram amounts of hydrogen peroxide (H2O2) in aqueous solution, a molecule difficult to detect as it lacks the nitroaromatic units, characteristic of trinitrotoluene (TNT) based explosives, which are usually targeted by traditional optical methods such as fluorescence. The same platform without any modifications can also be used to identify and quantify comparable amounts of 1,4-dinitrobenzene (DNB), a substitute molecule for TNT. These results highlight the capability of suspended-core fibers as small, cost-efficient and low-volume explosives sensors. © 2013 SPIE.