A collaboration between the UTS Centre for Forensic Science, the University of Canberra, the Australian Federal Police and Northern Illinois University has resulted in what is being claimed to be a forensic science world first with the preliminary development of a novel immunogenic method to detect latent fingermarks. The research also brings closer what is described as the "Holy Grail" of forensic fingerprinting – the ability to recover fingerprints from human skin.
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 can't be captured using traditional fingerprinting methods.
"We've 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," Spindler said. "The potential is there to go back to old cases to see what might now be recovered."
Recently published in Chemical Communications, a journal of the Royal Society of Chemistry, 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," Spindler said.
"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 that 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."