Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fingerprints provide clues to more than just identity

11.08.2008
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."

Researchers examined fingerprints in situ or lifted them from different surfaces such as glass, metal and plastic using common clear plastic tape. They then analyzed them with a mass spectrometry technique developed in Cooks' lab.

Mass spectrometry works by first turning molecules into ions, or electrically charged versions of themselves, so their masses can be analyzed. Conventional mass spectrometry requires chemical separations, manipulations of samples and containment in a vacuum chamber for ionization and analysis. Cooks' technology performs the ionization step in the air or directly on surfaces outside of the mass spectrometer's vacuum chamber, making the process much faster and more portable, Ifa said.

The Purdue procedure performs the ionization step by spraying a stream of water in the presence of an electric field to create positively charged water droplets. Water molecules in the droplets contain an extra proton and are called ions. When the charged water droplets hit the surface of the sample being tested, they transfer their extra proton to molecules in the sample, turning them into ions. The ionized molecules are then vacuumed into the mass spectrometer to be measured and analyzed.

Researchers placed a section of tape containing a lifted fingerprint on a moving stage in front of the spectrometer. The spectrometer then sprayed small sections of the sample with the charged water droplets, obtaining data for each section and combining the data sets to create an analysis of the sample as a whole, Ifa said. Software was used to map the information and create an image of the fingerprint from the distribution and intensity of selected ions.

Additional co-authors of the paper are Nicholas E. Manicke and Allison L. Dill, graduate students in Purdue's chemistry department.

The research was performed within Purdue's Center for Analytical Instrumentation Development located at the Bindley Biosciences Center in Purdue's Discovery Park.

Cooks' device, called desorption electrospray ionization or DESI, has been commercialized by Indianapolis-based Prosolia Inc., and the research was funded by Office of Naval Research and Prosolia Inc.

Writer: Elizabeth K. Gardner, (765) 494-2081, ekgardner@purdue.edu
Sources: R. Graham Cooks, (765) 494-5263, cooks@purdue.edu
Demian Ifa, (765) 494-5262, difa@purdue.edu
Purdue News Service: (765) 494-2096; purduenews@purdue.edu

Elizabeth K. Gardner | EurekAlert!
Further information:
http://www.purdue.edu

More articles from Information Technology:

nachricht Magnetic Quantum Objects in a "Nano Egg-Box"
25.07.2017 | Universität Wien

nachricht 3-D scanning with water
24.07.2017 | Association for Computing Machinery

All articles from Information Technology >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

 
Latest News

CCNY physicists master unexplored electron property

26.07.2017 | Physics and Astronomy

Molecular microscopy illuminates molecular motor motion

26.07.2017 | Life Sciences

Large-Mouthed Fish Was Top Predator After Mass Extinction

26.07.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>