NCJ Number
203121
Journal
Journal of Forensic Sciences Volume: 48 Issue: 5 Dated: September 2003 Pages: 1065-1074
Date Published
September 2003
Length
10 pages
Annotation
This preliminary investigation provides a basis for future studies to determine the feasibility of Raman spectroscopy and Raman chemical imaging for condom lubricant trace detection in case type samples.
Abstract
Although a male sex offender's use of a condom prevents the depositing of biological evidence in the commission of a sexual assault, important evidence can be obtained by identifying the condom's lubricant components. The presence or absence of these materials can help corroborate or undermine the statements of an alleged victim or an accused. Commercially available condoms of all types can contain fine powders, lubricants, and/or spermicides in various combinations. The recent accessibility of Raman instrumentation to the forensic scientist may provide an alternative method for characterizing condom lubricant traces through the use of Raman spectroscopy and Raman chemical imaging. Chemical imaging has the ability to identify condom lubricant components in the presence of one another, so long as they have unique Raman spectra. In Raman spectroscopy, energy levels of molecules and solids are probed by monitoring the frequency shifts present in scattered light. In the past several years, a number of key technologies have been introduced into wide use that have facilitated the utility and development of Raman spectroscopy. These technologies include high efficiency solid state lasers, holographic notch rejection filters, and silicon CCD detectors. Raman chemical imaging combines microscopy, digital imaging, and Raman spectroscopy to elicit molecular based information from materials. Raman chemical imaging expands on conventional Raman spectroscopy to characterize multiple condom lubricant components simultaneously in a manner that demonstrates heterogeneous sample mixtures both spectrally and spatially. In the current study, known reference materials, liquid and solid lubricant components of common condom brands, were successfully characterized by using Raman dispersive spectroscopy and Raman chemical imaging without extensive sample preparation inherent to other analytical methods, namely, Fourier transform-infrared analysis. The characterization of these materials shows the potential of this technique to become a routine screening method for condom lubricants. 9 figures and 29 references