A method based on profiling of dye components by electrospray ionization mass spectrometry (ESI/MS) is described for the characterization of ballpoint pen inks. The method involves benzyl alcohol (30 _L) extraction of ink from paper. The extracts of ink lines 1 and 5 mm in length are used for direct ESI/MS analysis in positive and negative modes, respectively. The instrumental analysis takes 3 min. Basic and acid dyes in the inks are detected in the positive and negative modes, respectively, with each dye yielding one or two characteristic ion peaks. The mass spectrum, which is mainly a compositional signature of the dyes in the ink, was not affected by the type of paper from which the ink was extracted, or by natural ageing of the ink on document in the absence of light. However, exposure to fluorescent illumination caused dealkylation of polyalkylated basic dyes and resulted in changes in the homologous distribution of the dyes. In this study, a total of 44 blue inks, 23 black inks, and 10 red inks have been analyzed, and the mass spectra were used to establish a searchable library. ESI/MS analysis provides a simple and fast way to compare ink specimens and in combination with on-line library search permits rapid screening of inks for forensic document investigations.
A reliable method for the characterisation of vodkas has been developed by application of solid‐phase microextraction (SPME) and gas chromatography/mass spectrometry (GCMS). Sixty‐four samples of commercial Canadian and American vodkas, and one sample each of Japanese and German vodkas, were investigated in this study. The procedure yielded reproducible chromatographic profiles. The detected components were ethyl esters of C8 to C18 fatty acids at μg litre−1 levels, various additives and contaminants. Distinctive profiles were observed for various brands. Markers for differentiating between Canadian and American vodkas were identified. The results of this study indicate that vodkas are differentiated by the combined effects of the original raw materials, any added substances, and differences in processing.
In support of the efforts to combat smuggling, as well as illegal sale and distribution of cigarettes, an analytical approach for the characterization of tobacco has been proposed and evaluated. It involves aqueous extraction of the filler tobaccos followed by direct analysis of the extracts by electrospray ionization-ion trap mass spectrometry (ESI-ITMS) in the negative mode. Typically, the deprotonated ions, [M - H](-), of organic acids (malic, citric, caffeic, quinic acid) and polyphenols (chlorogenic acid, rutin, scopoletin) were detected. MS/MS spectra of the ion at m/z 191, which is the [M - H](-) of quinic acid, citric acid, and scopoletin, and a fragment ion of chlorogenic acid were acquired. Significant differences in the MS and MS/MS spectra were observed between counterfeit samples and the corresponding authentic brand name cigarettes. Analysis of 25 commercial cigarettes showed that straight Virginia blends were readily distinguished from the blended products containing different tobacco types (Virginia, burley, and Oriental). The former exhibited consistently higher relative abundances of m/z 353 (chlorogenic acid) to m/z 133 (malic acid) in the MS spectra (0.9-1.2 vs 0.4-0.6) and higher intensity ratios of m/z 176 (scopoletin) to m/z 173 (0.4-0.8 vs 0.1-0.3) and of m/z 127 (quinic acid) to m/z 173 (0.7-1.0 vs 0.3-0.5) in the MS/MS spectra. Evidence is presented to demonstrate that the spectral differences were related not only to the tobacco type (Virginia, burley and Oriental) but also to the tobacco part (stem, lamina) used in the manufacture of the cigarettes.
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