by Kenneth Ujevich
This study aimed to develop a liquid-chromatography mass spectrometry (LC-MS) method to compare the efficiency of various sampling materials for the collection and subsequent analysis of organic gunshot residues (OGSR). Seven sampling materials, two swab-type and five stub-type collection materials, were tested. The evaluation of sampling materials was carried out by first analyzing blank extracts of the materials to check for potential interferences and determining matrix effects. Based on these results, the best four materials, namely cotton buds, polyester swabs, a tape from 3 M, and PTFE were compared in terms of collection efficiency during shooting experiments using a set of 9 mm Luger ammunition. It was found that the tape was capable of recovering the highest amounts of OGSR, leading to the conclusion that tape collection may be the best method for both organic and inorganic GSR collection.
Anne-Laure Gassner, Céline Weyermann. “LC–MS method development and comparison of sampling materials for the analysis of organic gunshot residues.” Forensic Science International. Volume 264, July 2016, Pages 47-55, ISSN 0379-0738, http://dx.doi.org/10.1016/j.forsciint.2016.03.022.