August 20, 2012 -
Researchers, headed by Dr. Bin Su, from Zhejiang University in Hangzhou, China have created a technique using electrogenerated chemiluminescence to make fingerprints glow when exposed to an electric charge. This dramatizes the appearance of the fingerprints, giving details on grooves and ridges.
Discovery News described how the method works, based on Su’s research paper:
“A fingerprint is pressed onto an electrode that’s either in the form of indium tin oxide glass or a stainless steel sheet. The electrode is dipped into a specialized chemical solution. Oils, dirt and other particles in the fingerprint inhibit the electrochemiluminescence reaction, but the reaction could occur in the spaces in between. When a suitable voltage is applied to the electrode, the bare electrode surface, including the fingerprint’s grooves, light up and can be imaged using a CCD camera sensor. A different chemical solution that sticks to the amino acids of the fingerprint does the opposite, causing the fingerprint’s ridges to light up and not the areas in between.”
Su said it is possible to light up either the substrate, which produces a negative image or the fingerprint glow, which produces a positive image. For both cases, the scanned fingerprint can project fine details of the fingerprint like ridge patterns, branches, ends of lines, and even pore size.
The process is simple and handy. Although it has only been tested in the laboratory, Su told Discovery News that it could be applied in real life: “Fingerprints on real life substrate can be transferred by lifting them from the substrates to electrodes using a special tape.” The research team experimented on varying substrates including coin, desk, computer screen and a disk.
Do you think illuminated fingerprints may replace fingerprint dusting in forensics?