Tahtouh, M, Scott, SA, Kalman, JR & Reedy, BJ 2011, 'Four Novel Alkyl 2-Cyanoacylate Monomers And Their Use In Latent Fingermark Detection By Mid-Infrared Spectral Imaging', Forensic Science International, vol. 207, no. 1-3, pp. 223-238.View/Download from: Publisher's site
Four novel alkyl 2-cyanoacrylate monomers (alkyl = 1-cyanoethyl, 2-cyanoethyl, trideuteromethyl and pentadeuteroethyl) have been tested for their ability to develop latent fingermarks that can then be visualized usingmid-infrared spectral (chemical) imaging. Each of the fourmonomers was chosen for its potential to produce a strong, isolated infrared spectral band in its corresponding polymer (to provide spectral contrast against most backgrounds), as well as for its potential ability to be fumed onto fingermarks in the manner of conventional ethyl 2-cyanoacrylate (superglue). With the exception of the 2-cyanoethyl 2-cyanoacrylate, which had to be fumed under reduced pressure, all of themonomers were found to be sufficiently volatile to be fumed in a conventional fuming cabinet. All four monomers polymerized selectively on fingermark ridges on a variety of non-porous and semi-porous surfaces, leading to excellent development of the fingermarks. Unfortunately, although high quality mid-infrared spectral images of the fingermarks could be formed for all of the polymers at various frequencies, the new CBBN or CD stretching vibrations did not give rise to strong enough absorption intensities for good contrast on difficult backgrounds such as polymer banknotes. However, in the 1-cyanoethyl 2- cyanoacrylate polymer, the presence of the additional nitrile group had the unintended but desirable effect of shifting the strong C55O absorption to higher frequencies, moving it away from interfering banknote absorptions. This enabled fingermark contrast to be achieved even against the intaglio printing on the banknotes.