A team of researchers have discovered a straightforward concept for identifying whether a culprit is male or female. It’s based on amino acid levels in fingerprints.
ALBANY, US: University at Albany research group, led by assistant chemistry prof Jan Halamek, is taking crime scene fingerprint identification to a new level.
Halamek and his team of researchers have discovered a straightforward concept for identifying whether a culprit is male or female. It’s based on the content in fingerprints specifically amino acids.
According to known literature, amino acid levels in the sweat of females are about twice as high as in males. There’s also a slightly different distribution, due mostly to hormonal differences. The same is true for amino acids left behind in fingerprints. Halamek’s research team has devised a simple method to back up these claims.
The team extracts amino acids from a fingerprint by transferring it onto a piece of plastic wrap. A hydrochloric acid solution is then placed onto the fingerprint, followed by heating. This process allows for the water-soluble amino acids to migrate into the acidic solution. From there, the team can easily view amino acid levels, distinguishing sex.
Halamek and his colleagues’ first tested this method on “mimicked fingerprint samples,” which they found to have a 99 percent accuracy of correct sex classification. From there, they set up a real crime scene scenario. Three female volunteers placed their fingerprints on five different surfaces, including a doorknob and a computer screen. Regardless of the surface type, Halamek’s team found it was possible to tell the fingerprint belonged to a woman.
“One of the main goals for this project was to move toward looking at the chemical content within the fingerprint, as opposed to relying on simply the fingerprint image,” said Halamek. “We do not intend to compete with DNA analysis or the databases used for identification. Instead we are aiming at differentiating between demographic groups, and more importantly, we are aiming at making use of fingerprints that are smudged or that don’t have an existing match.”
Halamek’s full study is published in the journal Analytical Chemistry.
© University at Albany News