There has been an increase in the use of condoms by sexual offenders, likely due to both to the risk of sexually transmitted diseases and to prevent the transfer of DNA evidence. The method developed by researchers at the University's Biomedical Research Centre (BMRC) can detect condom lubricant on fingermarks left by a suspect at a crime scene.
Condom lubricant can now be detected on fingermarks
Credit: Sheffield Hallam University
This can link a suspect, identified by their fingermark, to the crime in one analysis and can aid police in proving that an offence has taken place. And it is hoped the technique might be used to match lubricant found on a fingermark with residues from vaginal swabs collected from the victim.
Researchers successfully detected lubricant from two widely available condom brands on fingermarks for the first time, and the technique was proven to be successful even on fingermarks left several weeks before analysis.
And the academics hope the technique can eventually be used to identify distinctive lubricants that could indicate a specific condom manufacturer and possibly even a particular brand. This would allow the forensic case to be profiled in an even stronger way.
For the study, researchers used MALDI-MSI (matrix-assisted laser desorption/ionisation mass spectrometry imaging), a powerful technology that can be used to map fingermark ridge patterns.
Dr Simona Francese, from the University's BMRC, said: "Offenders are increasingly aware of forensic issues and it is common now for condoms to be used and removed from the scene of a sexual assault. However, they are less likely to consider the possibility of lubricant transferring onto their fingertips and then into fingermarks left at the scene.
"If condom lubricant can be detected in fingermarks it would improve the evidence for the prosecution by establishing the assailant's presence at the scene and, crucially, having had contact with a condom. This would enable forensic scientists to provide further support to the evidence in alleged cases of sexual assault."
Source: Sheffield Hallam University
Full bibliographic information
A novel matrix-assisted laser desorption/ionisation mass spectrometry imaging based methodology for the identification
of sexual assault suspects, Robert Bradshaw1, Rosalind Wolstenholme1, Robert D. Blackledge2, Malcolm R. Clench1, Leesa S. Ferguson1 and Simona Francese1*
1 - Sheffield Hallam University, Biomedical Research Centre, Howard Street, Sheffield S1 1WB, UK
2 - Formerly of the U.S. Naval Criminal Investigative Service Regional Forensic Laboratory, San Diego, CA, USA
Rapid Commun. Mass Spectrom. 2011, 25, 415–422
(wileyonlinelibrary.com) DOI: 10.1002/rcm.4858