BEIJING, July 23 (Xinhuanet) -- Crime scene forensic scientists are excited about a new method of collecting fingerprints using tape made from gelatin that could enable them to chemically analyze prints gathered at crime scenes, yielding more specific information about what a criminal eats and perhaps their gender and race.

    Standard methods for collecting fingerprints at crime scenes, which involve powders, liquids or vapors, can alter the prints and erase valuable forensic clues, including traces of chemicals that might be in the prints.

    The gel tape can pick up prints from a variety of surfaces, including door handles, mug handles, curved glass and computer screens, just as conventional fingerprint techniques can.

    The gelatin is then irradiated with infrared rays inside a highly sensitive instrument that rapidly takes a kind of "chemical photograph," identifying molecules within the print in 30 seconds or less, said physical chemist Sergei Kazarian at Imperial College London.

    "More volunteers need to be tested for statistical information on fingerprints with regard to race, sex and so on, but we believe this will be a powerful tool," he told LiveScience.

    Fingerprints contain just a few millionths of a gram of fluid, or roughly the same amount of material in a grain of sand. That might, however, be enough to determine valuable clues about a person beyond the print itself, such as their gender, race, diet and lifestyle, Kazarian and his colleagues find.

    For instance, preliminary results could identify males based on the greater amounts of urea in their fingerprints¡ªurea being the key ingredient of urine. The complex brew of organic chemicals within prints might also shed light on the age and race of people, and hold traces of items people came into contact with, such as gunpowder, smoke, drugs, explosives, or biological or chemical weapons.

    In addition, unlike conventional fingerprint techniques, the new method did not distort or destroy the original prints, instead keeping them intact and available for further analysis, the researchers said. Their findings are detailed in the Aug. 1 issue of the journal Analytical Chemistry.

    (Agencies)