Are you a fan of CSI? Are you intrigued by the sophisticated and technologically advanced devices which help David Caruso and his team to nail the criminals? The latest fingerprint test has helped give medical examiners and law enforcement officers a boost. While fingerprints have long been used to identify criminals, scientists have now taken the technology a step further. The latest fingerprint test, desorption electospray ionization (Desi), discovered by R Graham Cooks, a professor of chemistry at Purdue University, and his colleagues, can detect what the fingers have handled such as drugs, explosives or poisons. With just a tiny bit of electrically charged liquid sprayed on the fingerprint, scientists can detect compounds from the fingerprint molecules with a mass spectrometer.

The technology is not only applicable for identifying the compounds found on fingerprints, it actually reveals the evidence of the compound – arsenic or cocaine – in the shape of a person’s fingerprint. The technology therefore provides damning evidence to incriminate criminals. Fingerprints were tested from different surfaces including plastic, wood, paper and glass. Even smudged fingerprints or many sets of overlapping prints were successfully isolated using this technique.

Prosolia Inc., a small company in Indianapolis, has licensed the Desi technology from Purdue and is already selling such analyzers as add-ons to large laboratory mass spectrometers, which cost several hundred thousand dollars each. The price is too expensive for many crime laboratories although smaller, cheaper and portable versions are expected to be commercially available soon. The Desi technology is being used in crime investigation scenes although its original purpose is to detect cancer cells in the medical field.