title: Combination of prostate-specific antigen detection and micro-Raman spectroscopy for confirmatory semen detection.
abstract: Detecting prostate specific antigen (PSA) in a questioned body fluid stain or other sexual assault casework items strongly indicates the presence of semen and is extremely useful when no sperm cells are observed. However, it has several false-positives which may prevent confirmative semen classification. Namely, the presence of PSA and nucleated cells in male urine could lead a forensic examiner to an incorrect body fluid conclusion. Micro Raman spectroscopy is a molecular spectroscopy based on the inelastic scattering of monochromatic light and its potential to detect a wide range of body fluids has been demonstrated in recent years. In the present study, we show how the combination of PSA tests and micro Raman spectroscopy offers a simple, non-destructive and quick method for confirmatory semen detection. After positive PSA tests, micro Raman spectroscopy can easily corroborate semen presence and exclude the possibility of urine false positive detection. The sensitivity of this practice was demonstrated by measuring micro Raman spectra of diluted urine and semen (up to 1:100), as well as their spectra after extraction from cloth and swabs. These results strongly show the advantages of combining micro Raman spectroscopy and PSA tests when examining sexual assault casework items.
authors.affiliation: DNA and Forensic Biology Laboratory, Division of Identification and Forensic Science, Israel Police, National HQ, Haim Bar-Lev Road, Jerusalem, Israel. Electronic address: ifeine@gmail.com.
authors.forename: Ilan
authors.initials: I
authors.lastname: Feine
authors.affiliation: DNA and Forensic Biology Laboratory, Division of Identification and Forensic Science, Israel Police, National HQ, Haim Bar-Lev Road, Jerusalem, Israel. Electronic address: rongafny@police.gov.il.
authors.forename: Ron
authors.initials: R
authors.lastname: Gafny
authors.affiliation: Department of Chemical Research Support, Weizmann Institute of Science, 234 Herzl Street, Rehovot 7610001, Israel,. Electronic address: iddo.pinkas@weizmann.ac.il.
authors.forename: Iddo
authors.initials: I
authors.lastname: Pinkas
mesh_terms: D005554:Forensic Medicine; D006801:Humans; D008297:Male; D017430:Prostate-Specific Antigen; D012661:Semen / Q000737:chemistry*; D012742:Sex Offenses; D013059:Spectrum Analysis, Raman; D014556:Urine / Q000737:chemistry
chemical_list: D017430:Prostate-Specific Antigen
keywords: Body fluids; Forensic science; Prostate specific antigen; Raman spectroscopy; Semen and urine detection