Chemists at LSU may have a solution to this sticky problem. Researchers in the LSU Department of Chemistry including postdoctoral researcher Fabrizio Donnarumma, former undergraduate researcher and current LSU alum Eden E. Camp, graduate student Fan Cao and Roy Paul Daniels Professor of Chemistry Kermit K. Murray have developed an infrared laser ablation and vacuum capture system for fingermark sampling that takes mystery out of the process of identifying the chemical compositions of fingermarks at a crime scene. They’ve described the approach and instrumentation in a new paper published in the Journal of The American Society of Mass Spectrometry.

The idea started when Eden, an undergraduate chemistry student who had interned at the Louisiana State Police Crime Lab during the summer of 2015, approached Murray and Fabrizio with the idea of using their laser lab’s equipment to detect substances from fingermarks.

“I've always had a great interest in forensic science and I wanted my undergraduate research to reflect that,” Eden said. During her internship at the LSP Crime Lab, Eden started brainstorming ways that forensic experts could detect chemical substances from fingermarks. “The most challenging part was trying to determine a method of collection that lost the least amount of sample and wouldn't destroy the surface it was on.”

Fortunately, the Murray lab has extensive experience using lasers to ablate or remove tiny layers from various tissues for bioanalysis.

“We realized that if our techniques work for biomolecules as fragile as DNA and RNA, it should work with almost anything,” Fabrizio said. “We can capture almost anything that is on a surface. In this case, it just happened to be fingerprints.”

Together, Eden, Fabrizio, Fan and Murray came up with the idea to use the lasers in their lab to ablate fingermark materials from a surface, suck them into a filter, and then analyze them using spectrometry techniques. The technique could be used to capture and analyze a variety of molecules contained in a fingermark, including lipids, proteins, genetic material, or even trace amounts of explosives.