ISSN: 0022-1198
CODEN: JFSCA
Page Count: 14

A Methodology Based on NMR Spectroscopy for the Forensic Analysis of Condoms
Lee, GSH
University of St. Andrews, KY

Brinch, KM
Materials and Forensic Science, University of Technology, Sydney, NSW

Kannangara, K
Materials and Forensic Science, University of Technology, Sydney, NSW

Wilson, MA
Materials and Forensic Science, University of Technology, Sydney, NSW

Dawson, M
Materials and Forensic Science, University of Technology, Sydney, NSW

(Received 20 March 2000; accepted 1 August 2000)

Abstract

Both solution and solid state Nuclear Magnetic Resonance (NMR) spectroscopic techniques have been used to determine differences in commercially available condoms. Whilst solid state NMR is useful for determining the polymer backbone, it is not useful for forensic analysis due to the commonality of the latex condom. However solution NMR spectra obtained following a simple extraction procedure using hexane, provides a fingerprint of the additives in the lubricants. Following the development of a flow chart, basing decisions on the presence of particular peaks present in the solution spectra, 33 of 38 condoms could be individualized. Samples were also analyzed after having the lubricant manually removed and soaking the condom in water for 3 to 24 h. These experiments were performed to simulate a case of the sample having been used and disposed of by flushing down the toilet, as may be experienced in a case of a sexual assault. The results indicated that the only significant water soluble component was polyethylene glycol. The overall results suggest that the method developed may be a quick and useful technique in characterizing condoms. The information obtained can be used to provide associative evidence between suspect and crime, and so be useful in sexual assault cases.

Keywords:
forensic science, condom, polydimethylsiloxane, PDMS, polyethylene glycol, PEG, nonoxynol-9, nuclear magnetic resonance, NMR, identification systems

Paper ID: JFS15052J
DOI: 10.1520/JFS15052J
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