Preparation of a low-cost fingerprint powder that harnesses white light to emit long-lived phosphorescence

Scarlet L Hopkins; Kristen T Clarke; Matthew N Krosch; William J Gee

doi:10.1016/j.scijus.2023.04.013

Preparation of a low-cost fingerprint powder that harnesses white light to emit long-lived phosphorescence

Sci Justice. 2023 Jul;63(4):500-508. doi: 10.1016/j.scijus.2023.04.013. Epub 2023 May 6.

Authors

Scarlet L Hopkins¹, Kristen T Clarke¹, Matthew N Krosch², William J Gee³

Affiliations

¹ School of Environment and Science, Griffith University, 170 Kessels Road, Brisbane, QLD 4111, Australia.
² Quality Management Section, Forensic Services Group, Queensland Police Service, Brisbane, 4000 QLD, Australia.
³ School of Environment and Science, Griffith University, 170 Kessels Road, Brisbane, QLD 4111, Australia. Electronic address: W.Gee@griffith.edu.au.

PMID: 37453782
DOI: 10.1016/j.scijus.2023.04.013

Abstract

An inexpensive, commercially available doped strontium aluminate phosphor with long-lived afterglow has been prepared and assessed in the role of a luminescent fingerprint dusting powder. Blue, green, and aqua phosphorescence persisting for ca. 30 s was obtainable from treated fingermarks after charging the powders with the white light (400-700 nm) setting of a forensic light source. Imaging the phosphorescent afterglow enabled the elimination of background emissions encountered during latent fingermark examination. This was demonstrated by visualising fingermarks on substrates that possess inbuilt fluorescent security features and highly patterned substrate backgrounds, without any need for bespoke scientific equipment.

Keywords: Doped strontium aluminate; Fingerprint development; Fingerprint powder; Phosphorescence; White light.