Characterisation of 0.22 caliber rimfire gunshot residues by time-of-flight secondary ion mass spectrometry (TOF-SIMS): a preliminary study

The application of time-of-flight secondary ion mass spectrometry (TOF-SIMS ) for the characterisation of gunshot residue (GSR) from 0.22 caliber rimfi re ammunition is reported. Results obtained by TOF-SIMS were compared with conventional scanning electron microscopy (SEM) studies. As could be expect ed,TOF-SlMS exhibited greater elemental sensitivity than SEM equipped with energy dispersive X-ray detection (SEM-EDX), and was also capable of detect ing fragments characteristic of inorganic compounds. This preliminary study indicates that TOF-SIMS offers substantial potential fur forensic GSR exam inations as a complementary technique to SEM-EDX. In addition TOF-SIMS is a pplicable to the analysis of individual particles in the typical size range encountered in GSR casework. (C) 2001 Elsevier Science Ireland Ltd. All ri ghts reserved.