Application of a Modified 3D-PCSI-MS Ion Source to On-Site, Trace Evidence Processing via Integrated Vacuum Collection

• NCJ Number: 308880
• Journal: Journal of the American Society for Mass Spectrometry Volume: 35 Issue: 1 Dated: Jan 2024 Pages: 82-89
• Author(s): Ebenezer H. Bondzie; Adewale Adehinmoye; Brian T. Molnar; Patrick W. Fedick; Christopher C. Mulligan
• Date Published: January 2024
• Length: 8 pages
• Grant Number(s): 2017-R2-CX-0022
• Agencies: NIJ-Sponsored
• Publication Type: Research (Applied/Empirical)

Annotation

This article presents a project to develop a modified 3D-printed cone spray ionization source with integrated vacuum collection, for on-site forensic evidence screening, which allows for sample collection, onboard extraction, and more; it describes data collection methodology, product reliability testing, and outcomes.

Abstract

Trace evidence, including hair, fibers, soil/dust, and gunshot residue (GSR), can be recovered from a crime scene to help identify or associate a suspect with illegal activities via physical, chemical, and biological testing. Vacuum collection is one technique that is employed in recovering such trace evidence but is often done so in a targeted manner, leaving other complementary, chemical-specific information unexamined. Here, the authors describe a modified 3D-printed cone spray ionization (3D-PCSI) source with integrated vacuum collection for on-site, forensic evidence screening, allowing the processing of targeted physical traces and nontargeted chemical species alike. The reported form factor allows sample collection, onboard extraction, filtration, and spray-based ionization in a singular vessel with minimal handling of evidence by the operator. Utilizing authentic forensic evidence types and portable MS instrumentation, this new method was characterized through systematic studies that replicate CSI applications. Reliability in the form of false positive/negative response rates was determined from a modest, user-blinded data set, and other attributes, such as collection efficacy and detection limit, were examined. (Published Abstract Provided)