Researchers Make Fingerprints Glow With ElectrochemiluminescenceAug 17, 2012
That classic TV crime drama scene where the plucky forensic scientist dusts for fingerprints may become a thing of the past. Researchers from China’s Zhejiang Univ. in Hangzhou have created a technique that makes fingerprints -- both old and new -- glow in exquisite detail without destroying them.
The method enlists electrochemiluminescence, a phenomenon that causes a chemical solution to light up when hit with an electrical charge.
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.
Source: Christina Ortiz, Discovery News