New coating process reveals hard-to-develop fingerprints

Washington, May 12 (ANI): A new coating process may be able to reveal hard-to-retrieve fingerprints on nonporous surfaces without altering the chemistry of the print, say researchers.

Penn State professors have developed this conformal coating process.

"As prints dry or age, the common techniques used to develop latent fingerprints, such as dusting or cyanoacrylate --

SuperGlue-fuming often fail," said Robert Shaler, professor of biochemistry and molecular biology and director of Penn State's forensic sciences program.

This happens because most processes depend on the chemistry of the fingerprints, which are made of secretions of the body and react with chemicals to produce fluorescence.

The coating process, however, looks at the geometry of the fingerprints. The conformal coating applications suggested by Shaler and Akhlesh Lakhtakia, Charles Godfrey Binder Professor in engineering science and mechanics, use the physical properties of the fingerprint, not the chemistry of the substances left behind.

The researchers used a form of physical vapor deposition -- a method that uses a vacuum and allows vaporized materials to condense on a surface creating a thin film. With fingerprints, the point is to have the surface material's ridges and valleys-topography -- show up on the new surface so analysts can read them using an optical device without the necessity of chemical development or microscopy.

Forensic experts can, after the coating process, still examine the fingerprints.

"The body chemistry of the person who left the fingerprint can tell us some things," said Shaler. "If the suspect is older or younger or a lactating mother, for example."

So, using the coating process not only allows physical examination but also the chemical analysis of the fingerprints.

The researches tested this process using different materials such as, magnesium fluoride, chalcogenide glass and even tape.

A drawback of the process is that it can only be used on non-porous surfaces, surfaces that do not de-gas.

The researchers would also like to design a portable device that could be brought to a crime scene and produce readable fingerprints on site.

"We are in the process of redesigning the chamber and looking not just at fingerprints, but at other objects," said Lakhtakia.

"These would include bullets, cartridges, footprints, bite marks and lip impressions." Shaler and Lakhtakia have filed a provisional patent application on this application. (ANI)