Forensic Science Improves the Use of Fingerprint Technology
Fingerprints have long provided a method used for law enforcement to learn who was guilty of crimes. Now, fingerprinting technology has been improved. Adding a fluorescent product to directly highlight fingerprints makes it faster, easier and less expensive to gather fingerprint evidence.
The discovery made by the French Police and Gendarmerie, in combination with the FBI and Scotland Yard, was published in the Forensic Science International Journal. Fingerprints remain one of the most valuable tools in criminal investigations. The difficulty of using them when they are not printed in great enough detail, or are smudged, makes it difficult to enter them as evidence in a case.
This new technology is based on the combination of water, fats, salts, amino acids and, hopefully, DNA that is left behind whenever someone touches something. For a long time, Super Glue has been used to fume latent prints and bring them to the surface. The difficulties associated with this process prevent it from being an effective method in some cases. A second process uses a colorant that makes the fingerprint fluoresce. There are also problems with this method of printing, including the toxicity of the colorant and the high cost. It also takes as long as 48 hours to complete and has the potential to degrade the fingerprints, making them unusable.
When researchers from the Laboratoire de Photophysique et Photochimie Supramoleculaire et Macromeleculaire joined forces with the firm Crime Scene Technology in an attempt to overcome the problems in these two processes, they succeeded with the combination of cyanoacrylate and a molecule of the tetrazine family, making the smallest fluorescent colorants currently known. These molecules and the cyanoacrylate are fumed in the fingerprint support, causing them to adhere to it. Once a UV light is placed on the print, it is visible and clear enough for photographing. The discovery provides an effective method of retrieving latent prints that is faster and more affordable, without the risk of destroying DNA.