Citation

Perez JJ, Watson DA, Levis RJ. Anal. Chem. 2016; 88(23): 11390-11398.

Copyright

(Copyright © 2016, American Chemical Society)

DOI

10.1021/acs.analchem.6b01438

PMID

27783497

Abstract

Nonresonant laser vaporization combined with high resolution time-of-flight mass spectrometry enables analysis of a casing after discharge of a firearm revealing organic signature molecules including methyl centralite (MC), diphenylamine (DPA), N-nitrosodiphenylamine (N-NO-DPA), 4-nitrodiphenylamine (4-NDPA), a DPA adduct and multiple unidentified features not observed in previous mass spectral measurements. Collision-induced dissociation measurements of unknown GSR signature ions reveals inorganic barium and derivatives BaOH, BaOHCH3, BaCH3COO remaining from the primer. Offline principal component analysis and discrimination of the LEMS mass spectral measurements resulted in perfect classification of the gun shot residue with respect to manufacturer. Principal component analysis of recycled and reloaded casings resulted in classification of the penultimate manufacturer with accuracy of 64%.

Language: en