Rapid Screening and Confirmation of Organic GSR using Electrospray Mass Spectrometry.

摘要

The primary goal of this project was to develop a rapid separation and detection method for identifying common smokeless powder additives and their decomposition products using ultra performance liquid chromatography/ mass spectrometry. Smokeless powders can be used as the explosive component in pipe bombs as well as the propellant in modern ammunition. When used in ammunition, the powder is ignited by the primer and burns rapidly to produce a large volume of gas at high pressures and temperatures. It is this buildup of pressure that forces the projectile out of the firearm. In addition to the bullet, there is a release of primer chemicals and unburned/partially burned powder that may get deposited onto the shooters skin, hair, clothing, and in the nearby environment. These particulates are generally described as gunshot residue (GSR). To date, the major focus of GSR detection techniques has been on the recovery of primer residue, primarily barium, antimony, and lead. However, the removal of heavy metals from firearm ammunition, due to health and safety concerns, makes traditional techniques less effective for detecting GSR. An alternative approach focuses on the detection of the organic compounds present in the residue from the propellant. Because each manufacturer changes the composition of the propellant powder so that it performs in a specific manner, it is also possible to use variances in composition to differentiate between brands and potentially lots of the same powder.