title: Anti-theft device staining on banknotes detected by mass spectrometry imaging.
abstract: We describe the identification and limits of detection of ink staining by mass spectrometry imaging (MSI), as used in anti-theft devices (ATDs). Such ink staining is applied to banknotes during automated teller machine (ATM) explosions. Desorption electrospray ionization (DESI) coupled with high-resolution and high-accuracy orbitrap mass spectrometry (MS) and a moving stage device were applied to obtain 2D molecular images of the major dyes used for staining, that is, 1-methylaminoanthraquinone (MAAQ), rhodamine B (RB) and rhodamine 6G (R6G). MAAQ could not be detected because of its inefficient desorption by DESI from the banknote cellulose surface. By contrast, ATD staining on banknotes is perceptible by the human naked eye only at concentrations higher than 0.2 μg cm(-2), whereas both RB and R6G at concentrations 200 times lower (as low as 0.001 μg cm(-2)) could be easily detected and imaged by DESI-MSI, with selective and specific identification of each analyte and their spatial distribution on samples from suspects. This technique is non-destructive, and no sample preparation is required, which ensures sample preservation for further forensic investigations.
authors.affiliation: ThomSon Mass Spectrometry Laboratory, Institute of Chemistry, University of Campinas - UNICAMP, 13083-970 Campinas, SP, Brazil; Technical-Scientific Police Superintendency, Criminalistic Institute Dr. Octávio Eduardo de Brito Alvarenga - IC-SPTC-SP, 05507-06 São Paulo, SP, Brazil.
authors.forename: Deleon Nascimento
authors.initials: DN
authors.lastname: Correa
authors.affiliation: Brazilian Federal Police, Scientific and Technical Department - PF, 70037-900 Brasília, DF, Brazil.
authors.forename: Jorge Jardim
authors.initials: JJ
authors.lastname: Zacca
authors.affiliation: National Institute of Metrology, Quality and Technology - INMETRO, 25250-020 Rio de Janeiro, RJ, Brazil.
authors.forename: Werickson Fortunato de Carvalho
authors.initials: WFC
authors.lastname: Rocha
authors.affiliation: National Institute of Metrology, Quality and Technology - INMETRO, 25250-020 Rio de Janeiro, RJ, Brazil.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Borges
authors.affiliation: National Institute of Metrology, Quality and Technology - INMETRO, 25250-020 Rio de Janeiro, RJ, Brazil.
authors.forename: Wanderley
authors.initials: W
authors.lastname: de Souza
authors.affiliation: Department of Chemistry, Federal University of Minas Gerais - UFMG, 31270-901 Belo Horizonte, MG, Brazil.
authors.forename: Rodinei
authors.initials: R
authors.lastname: Augusti
authors.affiliation: ThomSon Mass Spectrometry Laboratory, Institute of Chemistry, University of Campinas - UNICAMP, 13083-970 Campinas, SP, Brazil.
authors.forename: Marcos Nogueira
authors.initials: MN
authors.lastname: Eberlin
authors.affiliation: ThomSon Mass Spectrometry Laboratory, Institute of Chemistry, University of Campinas - UNICAMP, 13083-970 Campinas, SP, Brazil. Electronic address: pedro.vendramini@iqm.unicamp.br.
authors.forename: Pedro Henrique
authors.initials: PH
authors.lastname: Vendramini
keywords: DESI; Forensic science; MAAQ; MSI; Rhodamine