>>3633733 (pb Notable)
>The bureau report did not say how long ago the fingerprints were left on the documents or in what sequence, things beyond the scope of fingerprint technology.
Fingerprints provide clues to more than just identity August 7, 2008
WEST LAFAYETTE, Ind. - Fingerprints can reveal critical evidence, as well as an identity, with the use of a new technology developed at Purdue University that detects trace amounts of explosives, drugs or other materials left behind in the prints.
The new technology also can distinguish between overlapping fingerprints left by different individuals - a difficult task for current optical forensic methods.
A team led by R. Graham Cooks, Purdue's Henry Bohn Hass Distinguished Professor of Analytical Chemistry, has created a tool that reads and provides an image of a fingerprint's chemical signature. The technology can be used to determine what a person recently handled.
"The classic example of a fingerprint is an ink imprint showing the unique swirls and loops used for identification, but fingerprints also leave behind a unique distribution of molecular compounds," Cooks said. "Some of the residues left behind are from naturally occurring compounds in the skin and some are from other surfaces or materials a person has touched."
The team's research will be detailed in a paper published in Friday's (Aug. 8) issue of Science.
Demian R. Ifa, a Purdue postdoctoral researcher and the paper's lead author, said the technology also can easily uncover fingerprints buried beneath others.
"Because the distribution of compounds found in each fingerprint can be unique, we also can use this technology to pull one fingerprint out from beneath layers of other fingerprints," Ifa said. "By looking for compounds we know to be present in a certain fingerprint, we can separate it from the others and obtain a crystal clear image of that fingerprint. The image could then be used with fingerprint recognition software to identify an individual."
https://www.purdue.edu/uns/x/2008b/080807CooksFingerprints.html