Forensic Microscopy
Electron microscopy (EM) has a wide variety of applications in forensic investigation. Numerous crime-scene micro-traces, including glass and paint fragments, tool marks, drugs, explosives and gunshot residue (GSR) can be visually and chemically analyzed with scanning electron microscopy (SEM). The conclusions based on this analysis are critical as they can establish the nature of the crime, as well as who was involved.
Gunshot residue analysis
Criminal investigators are often faced with the daunting task of analyzing crime scenes where firearms were used. Gunshot residue (GSR) analysis is a standard technique for determining whether a given individual or firearm was involved in the incident in question. Established GSR analysis begins with SEM surveying of suspected GSR particles, which are typically 0.5 to 10 micrometers in size. If a matching particle is found, energy dispersive X-ray spectroscopy (EDS) is used within the SEM to identify the chemical composition of that particle. The most common search criteria are the presence of lead (Pb), barium (Ba), and antimony (Sb). Once a sample is confirmed to be the result of a gunshot, its characteristics can be used as supporting evidence in the investigation.
Traditionally this type of analysis was performed manually, and the forensic scientist would dedicate significant time to the characterization and comparison of evidence. The Thermo Scientific Phenom Perception GSR Desktop SEM is a dedicated tool specifically designed for gunshot residue analysis. The system features unique automation that enables you to speed up the analysis process, making it faster, easier, and more reliable. Ideally suited for any forensics laboratory that wants to save time and floor space, the Phenom Desktop SEM can also be applied to many other forensic applications, including ballistics, paint analysis, and fiber characterization.