This article reports a modified ambient mass spectrometry (MS) method, filter cone spray ionization (FCSI), specifically designed for simple, yet robust, processing of bulk forensic evidence and environmental samples using a fieldable MS system.
The complexity of field-borne sample matrices and the instrumental constraints of portable mass spectrometers (MS) often require that preparative steps be added prior to ambient MS methods when operated on-site, but the corresponding decrease in throughput and experimental simplicity can make field operation impractical. The paper-crafted source demonstrated in this project uses low-cost laboratory consumables to produce a conical structure that serves as a disposable, spray-based ionization source. Integrated extraction and filtration capabilities mitigate sample heterogeneity and carryover concerns and expedite sample processing, as characterized through the analysis of a variety of authentic forensic evidence types (e.g., abused pharma tablets, counterfeit/adulterated tablets, crystal-based drugs, synthetic marijuana, toxicological specimens) and contaminated soil samples. The data presented suggest that the FCSI-MS design could prove robust to the rigors of field-borne, bulk sample screening, overcoming the inefficiencies of other ambient MS methods for these sample classes. Novel applications of FCSI-MS are also examined, such as the coupling to trace evidence vacuum filtration media. (publisher abstract modified)