ISSN: 0022-1198
CODEN: JFSCA
Page Count: 14

Improved Enhancement of Ninhydrin Developed Fingerprints by Cadmium Complexation Using Low Temperature Photoluminescence Techniques
Kobus, HJ
Chief forensic scientist, South Australian Forensic Science Centre,

Stoilovic, M
Research associate, research fellow and professor, The Faculties, Australian National University, ACT

Margot, PAJ-L
Research associate, research fellow and professor, The Faculties, Australian National University, ACT

Warrener, RN
Research associate, research fellow and professor, The Faculties, Australian National University, ACT

(Received 6 June 1985; accepted 1 July 1985)

Abstract

Fingerprints developed with ninhydrin form stable, colored complexes when treated with various metal salts. Many of these colored complexes can be used to increase the sensitivity of detection of latent prints because of photoluminescent properties. The intensity of this photoluminescence is increased at low temperature (77K), and this is a common characteristic of each of the complexes formed with salts of the IIb group of the Periodic Table. Spectral characteristics of these Group IIb metal complexes and the influence of environmental factors on their formation are reported. These data have helped determine optimal conditions for the enhancement of ninhydrin developed fingerprints. Taking into account spectral characteristics, solubility, versatility, stability, and reproducibility, the use of the cadmium nitrate tetrahydrate complex is advocated for general use for fingerprint enhancement. The use of zinc nitrate is favored if toxicological considerations are paramount, but ninhydrin development has to be carefully controlled if optimal results are to be obtained. Limited applications for mercuric complexes are found when a red shift is desired to remove background effects.

Keywords:
forensic science, fingerprints, ninhydrin, luminescence, fingerprint enhancement, photoluminescence, IIb metal complexes, papers

Paper ID: JFS12273J
DOI: 10.1520/JFS12273J
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