Tuesday Feb 27
Analysis and Classification of Pre- and Post-burn Smokeless Powders by Thermal Desorption DART-TOFMS: A validation Study
Oral Presentation - 205B - 850-9 - 11:05am - 11:25am
Lennert, Emily - University of Central Florida/National Center for Forensic Science
Co-authors: Bridge, Candice - University of Central Florida/National Center for Forensic Science
Thermal desorption direct analysis in real time- time of flight mass spectrometry (TD-DART-TOFMS) is a novel technique in forensic analysis in which an independent thermal desorption unit is coupled to a DART-TOFMS. The sample is thermally desorbed in an enclosed chamber by the thermal desorption unit, allowing for more sensitive analysis compared to traditional DART-TOFMS.
In this study, pre- and post-burn smokeless powder extracts were analyzed by traditional DART-TOFMS and TD-DART-TOFMS. Unburned or partially burned smokeless powder particles and burned smokeless powder residues may be recovered following an explosive event, such as discharge of a firearm or an improvised explosive device (IED). Therefore, unburned and burned samples were analyzed to simulate possible real world evidence.
Smokeless powders were analyzed for the presence of several organic compounds of interest, including: nitroglycerin, diphenylamine, ethyl centralite, dinitrotoluene, phthalates, and others. Extracts of unburned, i.e. pre-burn, smokeless powders and post-burn smokeless powder residues were prepared following a simple extraction procedure using dichloromethane. While extraction is not necessary for DART-MS analysis, extracts were utilized to minimize sample variability, allowing for simple, direct comparison between the methods. DART-TOFMS and TD-DART-TOFMS results were compared using multivariate statistical approaches. Classification schemes were developed for pre- and post-burn smokeless powder extracts. Thermally desorbed samples were used as an external test set to test classification within the traditional DART-TOFMS models as part of the validation of the thermal desorption technique for smokeless powder analysis.
Rapid Monitoring of Engine Oil Deterioration by Positive and Negative-Ion DART - TOF Mass Spectrometry
Exposition Floor, Aisles 2000-2700 - 1070-3 - 1:00pm - 3:00pm
Harvath, Paul - General Motors LLC
Co-authors: Cody, Robert B - Jeol USA
Automobile engine oil is composed of base lubricating oil plus an additive package of carefully selected chemical components to protect this base oil. The combustion events of an internal combustion engine combined with heat, friction, and contamination from water and fuel eventually wear out the additive package leaving the base oil susceptible to degradation. Oxidation is the primary method for this oil degradation and is routinely measured by infrared spectrometry or titration techniques. DART - TOFMS, direct analysis in real time-time of flight mass spectrometry, offers a rapid precise monitoring of individual chemical components of the additive package and the oil.
Analysis of oil samples taken at 20-hour intervals of a 100-hour engine dynamometer test with direct analysis in real time (DART) time-of-flight mass spectrometry has been used to identify and monitor several key components of the engine oil. By varying the ionization modes of the DART, changes to the antioxidants, anti-wear additive components and the base oil were successfully monitored.
Thursday Mar 1
Analysis of Commercially Available Natural Vaping Products using Headspace Gas Chromatography and Direct Analysis Real Time Time of Flight Mass Spectrometry (DART-MS)
Exposition Floor, Aisles 2000-2700 - 1870-3 - 10:00am - 12:00pm
Smith, Mika E - Virginia Commonwealth University
Co-authors: Edinboro, Les - Quest Diagnostics , Peace, Michelle R - Virginia Commonwealth University , Poklis, Justin L - Virginia Commonwealth University , Turner, Joseph - Virginia Commonwealth University
Electronic cigarettes (e-cigs) began as an alternative to smoking a traditional cigarette but have rapidly become a way of consuming drugs other than nicotine (DOTNs). The addition of alkaloid-containing, plant-based products are emerging and advertised as 'all natural' that produce a range of effects that are stimulating, euphoric, and even 'a substitute for opium'. The objective of this research is to analyze e-liquids and their respective resins and powders for the pharmacologically active alkaloids that can be attributed to producing the marketed effects by Jeol JMS T100LC AccuTOF DART-MS. E-liquids were also submitted to volatile organic compounds analysis by headspace gas chromatography with a flame ionization detector (HS-GC-FID).
Eight e-liquids, five resins, and four powders purchased from Lotus Extracts and an e-liquid purchased from Bizarro were analyzed and as a 1:10 dilution by DART-MS. The data was analyzed using T.S.S Pro version 3.0 and other potential compounds were detected using a NIST 11.0 library. Volatiles were analyzed by HS-GC-FID using a Restek BAC-2 column.
The e-liquid products' ingredient labels only identified the plant product, propylene glycol, and vegetable glycerin. After presumptive analysis of the various samples, the compounds that were consistently detected included arecoline, arecaidine, apomorphine, nuciferine, mitragynine, 7-hydroxymitragynine, coumarin, PG, and VG. Volatile analysis by HS-GC-FID resulted in identification and quantitation of isopropanol and ethanol in five products. This study demonstrates the evolving industry for products containing psychoactive substances to be used in e-cigs. Public misconception that all 'natural' products are healthy/safe contribute to risk of public health, especially given the general lack of information on ingredient labels on these products. This research demonstrates the presence of psychoactive and potentially harmful substances are present in e-liquids intended to be vaped.
Preliminary Characterization of Sexual Assault Lubricants: Comparison Between DART-TOFMS, GC-MS, and FT-IR
Exposition Floor, Aisles 2000-2700 - 2190-44 - 1:00pm - 3:00pm
Baumgarten, Brooke R - University of Central Florida/National Center for Forensic Science
Co-authors: Bridge, Candice - University of Central Florida/National Center for Forensic Science, Maric, Mark - University of Central Florida/National Center for Forensic Science, Vadell-Orsini, Caterina R - University of Central Florida/National Center for Forensic Science
Unfortunately, sexual assaults are a reality in today's society. Increasing use of condoms reduces potential of recovering DNA evidence, and a novel approach for the analysis of other trace evidence is required. The characterization and classification of lubricants is a relatively new approach for analyzing unknown trace evidence that could be collected from the crime scene or the victim.
In this study, 20 samples from different sexual lubricant manufacturing types were tested: water-based, silicone-based, oil-based, and organic/edible lubricants, and personal hygiene products which could also be used in sexual assaults. Instrumental methods were developed for direct analysis in real time-time of flight mass spectrometry (DART-TOFMS), gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FTIR). Analytical protocols were designed to increase the identification of unique components in these lubricants to develop a classification scheme for unknown samples.
Neat lubricants, as well as solvent extracts, were analyzed in both positive and negative ionization modes using DART-TOFMS in replicates of five. Neat lubricants and extracts were also analyzed via FTIR in triplicate, and extracts were analyzed by GC-MS in triplicate. Multivariate statistical techniques were used to identify unique markers that describe each class within the larger dataset. Classification schemes were developed for each instrument individually.
The outcomes of the classification schemes are expected to separate the different manufacturing types into groups, and sub-classes within each manufacturing type. The classification schemes developed from this preliminary study will affect the forensic trace evidence community by aiding in future exploitation of evidence found at a crime scene based on the data, thus providing investigative leads and innovative techniques in the analysis of trace evidence.
The Evaluation of Sexual Assault Evidence Using Direct Analysis in Real Time Time-of-Flight-Mass-Spectrometry (DART-TOFMS) and Gas Chromatography (GC-MS)
Exposition Floor, Aisles 2000-2700 - 2190-42 - 1:00pm - 3:00pm
Moustafa, Yasmine - University of Central Florida/National Center for Forensic Science
Co-authors: Bridge, Candice - University of Central Florida/National Center for Forensic Science
Suspects in sexual assault cases are commonly identified by analyzing seminal fluid that remains at the crime scene for the DNA profile. However, the use of condoms in such crimes has been on the rise, prevention the deposition of biological fluid. As a result, sexual assault evidence should also include the analysis of condom lubricants to support the current analysis that is being conducted. However, to ensure that this type of analysis is beneficial for sexual assault investigations, an important consideration is the risk of false positives from the inherent residues of personal hygiene products (PHPs) found on the skin of the victim or at the crime scene. Therefore, the aim of this study is to present a classification scheme to mitigate the predicament of misidentifying unknown samples.
In this study, 32 samples including 12 personal lubricants, 10 condoms, and 10 PHPs, were analyzed using DART-TOFMS and GC-MS. The results were statistically treated using hierarchical cluster analysis, principal component analysis, and linear discriminant analysis. The statistical classifications from both DART-TOFMS and GC-MS were compared to evaluate the advantages and disadvantages of each analytical method to differentiation sexual lubricants from PHPs in sexual assault evidence.
The presentation will disclose a classification scheme to differentiate sexual lubricants from PHPs using two instrumental methods. Additionally, the use of statistics in providing accurate classification and discrimination will be discussed. The attendees will learn how unknown samples can be classified into sample groups and how instrumental methods for sexual assault evidence can be evaluated and compared.
A Validated and Rapid Method for the Quantification of Psychoactive Materials in Complex Plant Matrices Using Direct Analysis in Real Time-High Resolution Mass Spectrometry
Exposition Floor, Aisles 2000-2700 - 2190-31 - 1:00pm - 3:00pm
Fowble, Kristen Leigh - University at Albany, SUNY
Co-authors: Lesiak, Ashton D - University at Albany, SUNY, Musah, Rabi Ann - University at Albany, SUNY
The quantification of natural products in complex matrices is a common practice in a number of fields, including medicine and forensics, among others. When the analyte of interest is contained within a complex plant matrix, the steps towards its quantification are far from straightforward. Our objective was to establish a procedure for the quantification of psychoactive materials found in plants being abused as 'legal highs', using an ambient ionization mass spectrometry technique that would greatly reduce the sample preparation typically required using traditional methods. Specifically, we describe an FDA validated method for the quantification of psychoactive atropine in Datura spp. seeds using direct analysis in real time-mass spectrometry. Calibration curves for atropine in a 1:1 v/v ethanol/water solvent using atropine-D3 as an internal standard were obtained over a linear range of 0.49 to 500 ppm. The limits of detection and quantification were determined to be 0.49 ppm and 0.98 ppm, respectively. D. stramonium, D. ferox and D. inoxia seeds were extracted and analyzed. Average concentrations of 15.32 +/- 0.15 ppm of atropine in the D. stramonium extract and 1.07 mg/g per seed were determined. The results compared well with reported levels determined using traditional approaches. Atropine in seed extracts of D. inoxia and D. ferox fell below the lower limit of quantification, but the extrapolated concentrations of atropine in their extracts were 0.83 +/- 0.14 ppm and 0.76 +/- 0.05 ppm, respectively. The results indicate that DART-MS can be used as a rapid means to quantify atropine in plant samples while avoiding significant sample preparation steps. Furthermore, the method can be applied to the quantification of other biomarkers in plant materials, despite the complexity of the plant matrix.
This work was supported by the National Institute of Justice (grant 2015-DN-BX-K057).
Detection and Identification of Plant-Based Legal Highs Based on Headspace Chemical Signatures Determined by SPME-Facilitated Direct Analysis in Real Time Mass Spectrometric Analysis
Exposition Floor, Aisles 2000-2700 - 2190-30 - 1:00pm - 3:00pm
Fogerty, Meghan G - University at Albany, SUNY
Co-authors: Musah, Rabi Ann - University at Albany, SUNY
The United Nations Office on Drugs and Crime has identified 20 plant species that are increasingly being used as 'legal highs' (i.e. psychoactive products that remain unscheduled). Their legal status shields users and traffickers of these products from prosecution. Although the bulk of these materials are not cultivated in Europe or the United States, they are imported from various regions of the world including Asia, Africa and South America, and are thus readily available. A major challenge to the legislation of the use and sale of these substances is that it is extremely difficult to distinguish them from innocuous plant-based products such as herbs, spices, and foods. The ability to do so would be especially useful for Border Protection Agents, so that commercial cargo can be screened for their presence. We sought to address this issue by developing a method that would enable detection of diagnostic small-molecule chemical signatures indicative of the presence of plant-based legal highs. In this approach, the headspace volatiles of 'legal high' plant materials are concentrated on polydimethylsiloxane (PDMS) SPME fibers, which are subsequently analyzed by direct analysis in real time-high resolution mass spectrometry (DART-HRMS). The observed chemical signatures are then subjected to multivariate statistical analysis approaches to enable classification and identification of the plant material. Kernel discriminant analysis (KDA) of the DART-MS data showed that the headspace signature could be used to accurately identify the bulk material. External validation was also performed to assess the reliability of the technique and was 100% accurate in all tests. These results demonstrate proof-of-concept for the creation of a database against which cargo-container derived headspace can be screened for the detection and identification of plant-based legal highs.
This work was supported in part by the United States National Institute of Justice (grant 2015-DN-BX-K057).
Establishing Exposure to Plant-Based Psychoactive Materials by Mapping Diagnostic Biomarkers in Fingerprints—A MALDI Mass Spectrometry Imaging Study
Exposition Floor, Aisles 2000-2700 - 2190-34 - 1:00pm - 3:00pm
Longo, Cameron M - University at Albany, SUNY
Co-authors: Musah, Rabi Ann - University at Albany, SUNY
One approach to evading prosecution for illicit drug use is to utilize currently unscheduled substances such as psychoactive plants. Barriers to legislating the use of such substances include the absence of standard protocols for their identification and the non-existence of methods that establish a connection between the abuser and the substance abused. To address this, our objective was to develop a technique by which evidence of contact with these mind-altering substances could be linked to an individual, as this would provide valuable information to law enforcement and healthcare practitioners alike. We demonstrate here that prior handling of plant-based psychoactive materials can be established through detection of diagnostic biomarkers by SpiralTOF matrix-assisted laser desorption ionization high-resolution mass spectrometry imaging. Furthermore, the compounds remain detectable in the fingerprint even after the print has aged. Plant products representing several relevant species were handled by rubbing the material between the fingers, whereafter fingerprints were deposited and prepared for analysis by SpiralTOF MALDI MS. Ion images of selected m/z values showed the spatial distributions of diagnostic small molecules indicative of exposure to the psychoactive plant materials. These included dimethyltryptamine from Mimosa hostilis and Psychotria viridis, and harmala alkaloids derived from Peganum harmala, as well as others. Importantly, the observed images were identical to those generated using endogenous lipids such as oleic acid. Plant biomarkers in fingerprints remained detectable for at least one week after being deposited. The findings illustrate that handling of psychoactive plant material by an individual can be definitively established solely through visualization of fingerprint images based on plant biomarkers.
This work was supported by the United States National Institute of Justice (grant 2015-DN-BX-K057).