Glowing fingerprints leave old forensic techniques in the dust
After a brush with burglars, an Australian scientist has developed a new technique to 'dust' for fingerprints, creating a solution that makes fingerprints glow under blacklight.
A home burglary has led to a scientific breakthrough that has the potential to overhaul more than a century of established forensic practice, changing the way police dust for fingerprints at a crime scene.
When Australian scientist Dr Kang Liang's home was robbed, police dusted his house for prints but failed to turn up any significant clues. But the process led Liang to question whether there was a more effective way to survey a crime scene, and his materials science background soon produced an answer: fingerprints that glow.
Working with a team of scientists at Australia's CSIRO research facility, Liang developed a liquid that can be applied to nonporous surfaces, revealing glowing green fingerprints that appear under a blacklight in less than 30 seconds.
The liquid contains metal organic framework (MOF) crystals that bind to the residue left behind in a fingerprint, including fatty acids, proteins, peptides and salts. According to CSIRO, these MOF crystals create "an ultrathin coating that's an exact replica of the pattern" of the fingerprint, which can then be easily and clearly photographed for analysis. The colours of the glow can also be changed by altering the chemical make-up of the solution.
After watching the traditional print dusting process play out in his own home, Liang says his new method is much quicker and can be used where conventional dusting is not appropriate.
"Knowing that dusting has been around for a long time, I was inspired to see how new innovative materials could be applied to create even better results," he said.
"While police and forensics experts use a range of different techniques, sometimes in complex cases evidence needs to be sent off to a lab where heat and vacuum treatment is applied. Our method reduces these steps, and because it's done on the spot, a digital device could be used at the scene to capture images of the glowing prints to run through the database in real time."
While the resulting glow prints might look like something out of a UV rave club (or an episode of late '80s TV series "Night Court"), the MOF crystals are cheap and react quickly to emit a bright light. They also don't create dust or fumes that police run the risk of inhaling.
According to Liang, it's also the first time the crystals have been researched for forensics. The team is hoping to take their idea to law enforcement agencies to develop the technique for use in the field.