Improvement in fingerprint detection using Tb(III)-dipicolinic acid complex doped nanobeads and time resolved imaging.

Hauser, Frank M.; Knupp, Gerd; Officer, Simon

Abstract

This paper deals with the synthesis and application of lanthanide complex doped nanobeads used as a luminescent fingerprint powder. Due to their special optical properties, namely a long emission lifetime, sharp emission profiles and large Stokes shifts, luminescent lanthanide complexes are useful for discriminating against signals from background emissions. This is a big advantage because latent fingerprints placed on multicoloured fluorescent surfaces are difficult to develop with conventional powders. The complex of 2,6-dipicolinic acid (DPA) and terbium ([Tb(DPA)3]3-) is used for this purpose. Using the Stöber process, this complex is incorporated into a silica matrix forming nanosized beads (230-630nm). It is shown that the [Tb(DPA)3]3- is successfully incorporated into the beads and that these beads exhibit the wanted optical properties of the complex. A phenyl functionalisation is applied to increase the lipophilicity of the beads and finally the beads are used to develop latent fingerprints. A device for time resolved imaging was built to improve the contrast between developed fingerprint and different background signals, whilst still detecting the long lasting luminescence of the complex. The developed fingerprint powder is therefore promising to develop fingerprints on multicoloured fluorescent surfaces.

Citation

HAUSER, F.M., KNUPP, G. and OFFICER, S. 2015. Improvement in fingerprint detection using Tb(III)-dipicolinic acid complex doped nanobeads and time resolved imaging. Forensic science international [online], 253, pages 55-63. Available from: https://doi.org/10.1016/j.forsciint.2015.05.010

• Journal Article Type: Article
• Acceptance Date: May 8, 2015
• Online Publication Date: May 16, 2015
• Publication Date: Aug 31, 2015
• Deposit Date: Mar 2, 2016
• Publicly Available Date: May 17, 2016
• Journal: Forensic Science International
• Print ISSN: 0379-0738
• Electronic ISSN: 1872-6283
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 253
• Pages: 55-63
• DOI: https://doi.org/10.1016/j.forsciint.2015.05.010
• Keywords: Terbium (III) dipicolinic acid complex; Silica-based nanobeads; Lanthanide luminescence; Fingerprint powder
• Public URL: http://hdl.handle.net/10059/1403