NCJ Number
153470
Journal
Journal of Forensic Identification Volume: 45 Issue: 1 Dated: (January/February 1995) Pages: 5-18
Date Published
1995
Length
14 pages
Annotation
The use of luminescent chemicals to enhance fingerprints developed with cyanoacrylate fuming is a well-established procedure in most fingerprint laboratories; the current study evaluated two luminescent stains commonly used in fingerprint work (Rhodamine 6G and Basic Yellow 40) and two other stains (Basic Red 28 and Styryl 7).
Abstract
Freon-free single dye and mixed dye solutions were developed and evaluated as cyanoacrylate stains. Spectral properties, including absorption and emission spectra, were recorded for fingerprints on white plastic developed with cyanoacrylate and treated with each dye solution. After drying, fingerprints were rinsed with distilled water to remove background staining. Luminescence was measured using excitation from a tunable light source, and emissions were observed using an appropriate interference filter. The two stains, Basic Red 28 and Styryl 7, proved to be of significant interest for fingerprint detection. Fingerprints treated with Basic Red 28 absorbed in the blue-green at 495 nm and gave a strong orange-red luminescence at 585 nm. On the other hand, Styryl 7 absorbed in the green at 555 nm and gave a strong, nearly infrared luminescence at 680 nm. The only disadvantage noted with dye solutions containing Styryl 7 was that this compound was not particularly stable. Treated fingerprints tended to change color and lose luminescence over time. The authors conclude that both Styryl 7 and Basic Red 28 offer advantages on highly luminescent surfaces that interfere with conventional stains such as Basic Yellow 40 and Rhodamine 6G. 2 references, 1 table, and 8 figures