U.S. flag

An official website of the United States government, Department of Justice.

Bank Security Dye Packs: Synthesis, Isolation, and Characterization of Chlorinated Products of Bleached 1-(Methylamino) Anthraquinone

NCJ Number
Journal of Forensic Sciences Volume: 51 Issue: 6 Dated: November 2006 Pages: 1276-1283
James M. Egan Ph.D.; Michael Rickenbach Ph.D.; Kim E. Mooney Ph.D.; Chris S. Palenik Ph.D.; Rebecca Golombeck B.S.; Karl T. Mueller Ph.D.
Date Published
November 2006
8 pages
This study examined the chemical reaction that occurs when a suspect in a bank robbery uses chlorine bleach in an attempt to remove colored 1-(methylamino)anthraquinone (MAAQ)--a red dye stain activated on banknotes taken in a bank robbery--from stolen banknotes.
The study found a new, facile synthetic route for chlorinated MAAQ derivatives. The synthetic route involved Ultra Clorox bleach as the chlorine source, iron chloride as the catalyst, and MAAQ as the starting material. This resulted in a three-component product mixture. All compounds were produced in solution as a mixture and were separated and analyzed with complementary analytical techniques. Products were isolated and probed with nuclear magnetic resonance (NMR) for the purpose of assigning the chromatographic peaks to monochlorinated MAAQ isomers: 2-chloro-1-(methylamino)anthraquinone and 4-chloro-1-(methylamino)anthraquinone. A description of the methods used addresses the synthesis of materials used, the use of thin-layer chromatography (TLC), the use of gas chromatography/mass spectrometry (GC-MS), the use of liquid chromatography (LC), liquid-state NMR, and micro X-ray fluorescence and scanning electron microscopy. Although GC-MS was sufficiently sensitive to detect all of the chlorinated products, it was not definitive enough to identify the structural isomers. Liquid-state NMR spectroscopy was used to reveal structurally the ortho- and para-monochlorinated isomers once sufficient material was properly isolated. 8 figures and 16 references