Transforming crime scene forensics
An Australian forensic science researcher has achieved a world first with the preliminary development of a novel immunogenic method that could recover usable fingerprints from old evidence and difficult surfaces.
An Australian forensic science researcher has achieved a world first with the preliminary development of a novel immunogenic method that could recover usable fingerprints from old evidence and difficult surfaces.
Despite fingerprinting being essentially the foundation technique of modern forensic science, only a fraction of all the fingermarks at a crime scene are actually detected.
Now the work of forensic science researcher Dr Xanthe Spindler at the University of Technology Sydney (UTS) in Australia has made an important step towards recovering usable fingerprints from old evidence and surfaces long considered too difficult by crime scene investigators.
The collaboration between the UTS Centre for Forensic Science, the University of Canberra, the Australian Federal Police and Northern Illinois University has resulted in a forensic science world first with the preliminary development of a novel immunogenic method to detect latent fingermarks.
The new method, developed by Dr Spindler as part of her PhD work, uses antibodies designed to target amino acids and can detect aged, dry and weak fingerprints that cant be captured using traditional fingerprinting methods.
Weve been able to successfully target amino acids on non-porous surfaces for the first time, with promising results in enhancing aged and degraded fingermarks that typically give poor results with traditional powdering and cyanoacrylate fuming, Dr Spindler said. The potential is there to go back to old cases to see what might now be recovered.
The work is also a step in pursuit of the Holy Grail as Dr Spindler calls it, a reliable method for recovering fingerprints from human skin.
Current techniques of powdering and fuming have never worked well on skin, with the ability to only enhance fingermarks less than three hours old, said Dr Spindler.
The use of immunogenic reagents targeted at specific markers in body fluids will improve the ability to enhance fingermarks on problematical surfaces such as human skin.
On other surfaces, existing methods are most effective recovering fresh fingermarks that contain a reasonable level of moisture. That has meant people with dry skin are weak donors and evidence is rapidly degraded in dry conditions or after long storage.
The targeting of amino acids in fingerprint detection has been around since the mid-50s, but its use has been limited largely to porous surfaces like paper because of the fragility of amino acid secretions on non-porous surfaces.
Our work has been a proof-of-concept for a reagent that links amino acid-binding antibodies to gold nanoparticles, with the nanoparticles giving sharper detail in developed fingerprints.
With the support of the Australian Federal Police it is hoped to build on the results to develop a reliable and cost-effective technique with the potential to deliver transformational outcomes for law enforcement.
