Analyzing Brazilian Vehicle Documents for Authenticity by Easy Ambient Sonic-Spray Ionization Mass Spectrometry

: Using desorption/ionization techniques such as easy ambient sonic‐spray ionization mass spectrometry (EASI‐MS), it is possible to analyze documents of Brazilian vehicles for authenticity, providing a chemical profile directly from the surface of each document. A method for the detection of counterfeit documents is described, and the falsification procedure is elucidated. Forty authentic and counterfeit documents were analyzed by both positive and negative ion modes, EASI(±)‐MS. EASI(+)‐MS results identified the presence of (bis(2‐ethylhexyl)phthalate plasticizer and of dihexadecyldimethylammonium biocide in both types of documents. For EASI(−)‐MS results, the 4‐octyloxybenzoic acid additive ([M + H]+: m/z 249) is present only in counterfeit documents. It was also found that counterfeit vehicle documents are produced via Laserjet printers. Desorption/ionization techniques, such as EASI‐MS, offer therefore, an intelligent way to characterize the counterfeiting method.