Direct analysis in real time mass spectrometry for analysis of sexual assault evidence

Department of Chemistry, University at Albany, State University of New York (SUNY), 1400 Washington Ave, Albany, NY 12222, USA.
Rapid Communications in Mass Spectrometry (Impact Factor: 2.25). 05/2012; 26(9):1039-46. DOI: 10.1002/rcm.6198
Source: PubMed


Sexual assault crimes are vastly underreported and suffer from alarmingly low prosecution and conviction rates. The key scientific method to aid in prosecution of such cases is forensic DNA analysis, where biological evidence such as semen collected using a rape test kit is used to determine a suspect's DNA profile. However, the growing awareness by criminals of the importance of DNA in the prosecution of sexual assaults has resulted in increased condom use by assailants as a means to avoid leaving behind their DNA. Thus, other types of trace evidence are important to help corroborate victims' accounts, exonerate the innocent, link suspects to the crime, or confirm penetration.
Direct Analysis in Real Time Mass Spectrometry (DART-MS) was employed for the comprehensive characterization of non-DNA trace evidence associated with sexual assault. The ambient ionization method associated with DART-MS is extremely rapid and samples are processed instantaneously, without the need for extraction, sample preparation, or other means that might compromise forensic evidence for future analyses.
In a single assay, we demonstrated the ability to identify lubricant formulations associated with sexual assault, such as the spermicide nonoxynol-9, compounds used in condom manufacture, and numerous other trace components as probative evidence. In addition, the method can also serve to identify compounds within trace biological residues, such as fatty acids commonly identified in latent fingerprints.
Characterization of lubricant residues as probative evidence serves to establish a connection between the victim and the perpetrator, and the availability of these details may lead to higher rates of prosecution and conviction, as well as more severe penalties. The methodology described here opens the way for the adoption of a comprehensive, rapid, and sensitive analysis for use in crime labs, while providing knowledge that can inform and guide criminal justice policy and practice.

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    • "pills, capsules, solutions, pure or mixed powders, impregnated herbal materials, impurities, by-products, etc.), as well as their various chemical forms. One of the most promising analytical techniques for thorough identification of various compounds is Direct Analysis in Real Time (DART) [7] [8] mass spectrometry ion source used for fast analysis of drug mixtures [7] [8] [9] [10] [11] [12], which was among the first ambient ionization techniques requiring no sample preparation. Thus, solid and liquid materials can be detected in their native states. "
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    ABSTRACT: Application of a flowing atmospheric-pressure afterglow ion source for mass spectrometry (FAPA-MS) for the analysis of designer drugs is described. In this paper, we present application of FAPA MS for identification of exemplary psychotropic drugs: JWH-122, 4BMC, Pentedrone, 3,4-DNNC and ETH-CAT. We have utilized two approaches for introducing samples into the plasma stream; first in the form of a methanolic aerosol from the nebulizer, and the second based on a release of vapors from the electrically heated crucible by thermal desorption. The analytes were ionized by FAPA and identified in the mass analyzer. The order of release of the compounds depends on their volatility. These methods offer fast and reliable structural information, without pre-separation, and can be an alternative to the Electron Impact, GC/MS, and ESI for fast analysis of designer-, and other psychoactive drugs.
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    • "[11] [12] DART-MS provides the ability to sample material directly, without the need for extractions, sample preparation, or chromatographic separations. These beneficial qualities have allowed DART-MS to be applied towards an extremely wide range of analytes, including controlled substances, [13] [14] [15] [16] [17] [18] [19] pesticides, [20] fragrances, [21] pepper spray, [22] and residues associated with sexual assault, [13] [23] among many others. [24] [25] DART-MS is a means to not only simplify but also revolutionize sample analysis for the detection of designer drugs. "
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