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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.09.005 Byline: Kelly Virkler, Igor K. Lednev Keywords: Raman spectroscopy; Semen; Principal components; Statistical analysis; Forensic science; Body fluid identification Abstract: A great potential of Raman spectroscopy for non-destructive, confirmatory identification of body fluids at the crime scene has been reported recently (Virkler and Lednev, Forensic Sci. Int. 2008). However, that analysis was carried out on only one sample of each body fluid and did not take into account any variations that might occur between different donors of the same fluid. This paper reports on the role of heterogeneity within a sample as well as among multiple donors for human semen. Near-infrared (NIR) Raman spectroscopy was used to measure spectra of pure dried human semen samples from multiple donors in a controlled laboratory environment. The major chemical components that contributed to the Raman spectrum of semen were determined and used to tentatively identify the principal spectral components. The issue of potential spectral variations that could arise between different donors of semen was also addressed. Advanced statistical analysis of spectra obtained from multiple spots on dry samples showed that dry semen is heterogeneous and its Raman spectra could be presented as a linear combination of a fluorescent background and three spectral components. The relative contribution of each of the three components varies with donor, so no single spectrum could effectively represent an experimental Raman spectrum of dry semen in a quantitative way. The combination of the three spectral components could be considered to be a spectroscopic signature for semen. This proof-of-concept approach shows the potential for Raman spectroscopy to identify an unknown substance to be semen during forensic analysis. Author Affiliation: Department of Chemistry, University at Albany, SUNY, 1400 Washington Avenue, Albany, NY 12222, United States Article History: Received 25 June 2009; Revised 9 September 2009; Accepted 10 September 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.05.015 Byline: Antonia Gronewold, Andrea Dettling, Hans T. Haffner, Gisela Skopp Keywords: Doxepin; Nordoxepin; Combined concentration; Concentration ratio; LC-MS/MS; Postmortem Abstract: Body fluids and tissues in eight doxepin (Dox)-related deaths were investigated in order to prove whether the individual concentration of Dox, the concentration sum of parent drug and its active metabolite N-desmethyldoxepin (NDox) or the concentration ratio Dox/Ndox valuably contribute to making a cause of death determination. Individual case histories were shortly described. Dox and NDox concentrations were determined by LC-MS/MS. Dox concentration measured from two cases was well within a concentration range considered therapeutic, whereas subtherapeutic dosing may have occurred in another two cases. There were two cases of fatal Dox ingestion, as well as a case of high dosage and advanced putrefaction, respectively. The liver concentration sum may be more useful if a fatal ingestion cannot be clearly separated from a person's medication usage. High concentrations could be observed in lung tissue, and combined concentrations of Dox and NDox may also be helpful in making a cause of death determination. There was a trend to a higher concentration sum in the brain with increasing combined levels in blood. Overall, the sum of the absolute figures allows a more accurate interpretation in Dox-related deaths as compared to the molar concentration ratio which may be helpful in acute ingestion. Determination of the N-desmethyl metabolite along with its parent is recommended and analysis should include more than a single specimen. Author Affiliation: Institute of Legal and Traffic Medicine, University Hospital, Voss-Str. 2, 69115 Heidelberg, Germany Article History: Received 13 February 2009; Revised 17 May 2009; Accepted 20 May 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.02.013 Byline: Kelly Virkler, Igor K. Lednev Keywords: Body fluid identification; Forensic biology; Non-destructive analysis; Raman spectroscopy; Biospectroscopy; Portable spectrometer Abstract: Body fluid traces recovered at crime scenes are among the most important types of evidence to forensic investigators. They contain valuable DNA evidence which can identify a suspect or victim as well as exonerate an innocent individual. The first step of identifying a particular body fluid is highly important since the nature of the fluid is itself very informative to the investigation, and the destructive nature of a screening test must be considered when only a small amount of material is available. The ability to characterize an unknown stain at the scene of the crime without having to wait for results from a laboratory is another very critical step in the development of forensic body fluid analysis. Driven by the importance for forensic applications, body fluid identification methods have been extensively developed in recent years. The systematic analysis of these new developments is vital for forensic investigators to be continuously educated on possible superior techniques. Significant advances in laser technology and the development of novel light detectors have dramatically improved spectroscopic methods for molecular characterization over the last decade. The application of this novel biospectroscopy for forensic purposes opens new and exciting opportunities for the development of on-field, non-destructive, confirmatory methods for body fluid identification at a crime scene. In addition, the biospectroscopy methods are universally applicable to all body fluids unlike the majority of current techniques which are valid for individual fluids only. This article analyzes the current methods being used to identify body fluid stains including blood, semen, saliva, vaginal fluid, urine, and sweat, and also focuses on new techniques that have been developed in the last 5-6 years. In addition, the potential of new biospectroscopic techniques based on Raman and fluorescence spectroscopy is evaluated for rapid, confirmatory, non-destructive identification of a body fluid at a crime scene. Author Affiliation: Department of Chemistry, University at Albany, SUNY, 1400 Washington Avenue, Albany, NY 12222, United States Article History: Received 16 December 2008; Revised 2 February 2009; Accepted 8 February 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2008.08.004 Byline: Kelly Virkler, Igor K. Lednev Keywords: Raman spectroscopy; Semen; Vaginal fluid; Saliva; Sweat; Blood Abstract: Raman spectroscopy was used to compare body fluids commonly found at crime scenes in a nondestructive manner. The dry traces of semen, vaginal fluid, sweat, saliva, and blood were analyzed using confocal Raman microscopy with a 785-nm excitation. The results show that the five fluids can be differentiated from one another by visual comparison of their Raman spectra, and that the laser radiation does not damage the sample. The Raman signature of each body fluid is specific and correlates with the known composition of the fluid. Dry traces of human and canine semen exhibited distinctly different Raman signatures. Overall, this preliminary study demonstrates the great potential of Raman spectroscopy for nondestructive, confirmatory identification of body fluids for forensic purposes. Author Affiliation: Department of Chemistry, University at Albany, SUNY, 1400 Washington Avenue, Albany, NY 12222, United States Article History: Received 23 June 2008; Revised 13 August 2008; Accepted 14 August 2008