John Goodpaster

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https://hdl.handle.net/1805/6679

Evaluation of the Odor Compounds Sensed by Explosive-Detecting Canines

The remote detection of explosives generally relies upon detecting volatile compounds that are emitted by the explosive itself. Detection of these compounds can be achieved through instrumentation or by specially trained canines. While instruments are designed and built to respond to particular chemical species, it is not always clear what chemical species generates a canine alert. In addition, canines have the ability to "generalize" and correctly alert to explosive formulations that are similar, but not identical, to those with which they have trained. This would tend to indicate that there are common chemical odors for some types of explosives. Dr. Goodpaster's research examines the effect of odor availability and differing odor compounds on canine detection. As the chemical composition of the headspace above explosive formulations is more completely understood, it should be possible to test the extent to which canine alerts correlate to the compounds of interest.

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Automated Derivatization and Identification of Controlled Substances via Total Vaporization Solid Phase Microextraction (TV-SPME) and Gas Chromatography/Mass Spectrometry (GC/MS)
(U.S. Department of Justice, Office of Justice Programs, 2018-11) Goodpaster, John V.
The hypothesis tested was that Total Vaporization - Solid Phase Microextraction (TV-SPME) will offer greater sensitivity than traditional liquid injection for controlled substances. In addition, TV-SPME was easily adapted to include either a pre-extraction or a post-extraction on-fiber derivatization step for thermally labile species. Project results were promising for all drug classes that were analyzed successfully by on-fiber derivatization as solutions. This discovery greatly improves the utility of the technique, since controlled substances are most often encountered in their solid forms in forensic science laboratories. The application of this technique to beverage samples and solid drug powders is of most interest, since these applications involve a significant decrease in sample preparation. Although not ideal for all analytes, TV-SPME with on-fiber derivatization could be a powerful technique for amine and hydroxylamine controlled substances, as well as GHB. The technique could increase analyst efficiency by reducing sample preparation time for these types of analytes. Thus, the main results of this project are a set of optimized derivatization methods that can be used in liquid injection or TV-SPfsME. This approach offers the possibility of automated sampling and derivatization for a wide variety of thermally labile compounds and the analysis of compounds that require no derivatization. Project design and methods are described. 4 figures and 1 table
Characterization of Automotive Paint Clear Coats by Ultraviolet Absorption Microspectrophotometry with Subsequent Chemometric Analysis
(2010-10) Liszewski, Elisa A; Lewis, Simon W; Siegel, Jay A; Goodpaster, John V.
Clear coats have been a staple in automobile paints for almost thirty years and are of forensic interest when comparing transferred and native paints. However, the ultraviolet (UV) absorbers in these paint layers are not typically characterized using UV microspectrophotometry, nor are the results studied using multivariate statistical methods. In this study, measurements were carried out by UV microspectrophotometry on 71 samples from American and Australian automobiles, with subsequent chemometric analysis of the absorbance spectra. Sample preparation proved to be vital in obtaining accurate absorbance spectra and a method involving peeling the clear coat layer and not using a mounting medium was preferred. Agglomerative hierarchical clustering indicated three main groups of spectra, corresponding to spectra with one, two, and three maxima. Principal components analysis confirmed this clustering and the factor loadings indicated that a substantial proportion of the variance in the data set originated from specific spectral regions (230–265 nm, 275–285 nm, and 300–370 nm). The three classes were well differentiated using discriminant analysis, where the cross-validation accuracy was 91.6% and the external validation accuracy was 81.1%. However, results showed no correlation between the make, model, and year of the automobiles.
Chemical Analysis as a Tool in Arson and Explosives Investigations
(Center for Translating Research Into Practice, IU Indianapolis, 2021-08-27) Goodpaster, John
In this presentation, Professor John Goodpaster discusses his translational research on “Chemical Analysis as a Tool in Arson and Explosives Investigations.” He explains how his laboratory uses science to design better approaches to identify trace amounts of explosives on post-blast debris from improvised explosive devices or ignitable liquid residues in debris from suspicious fires. He also talks about the best methods for training dogs to detect explosives of all kinds.
Chemical analysis of racing fuels using total vaporization and gas chromatography mass spectrometry (GC/MS)
(RSC, 2016-05) Bors, Dana; Goodpaster, John V.; Chemistry and Chemical Biology, School of Science
The National Hot Rod Association (NHRA) is the governing body of North American drag racing. As a supervisory agency, NHRA monitors racing fuels for regulatory purposes and quality control. In this paper, total vaporization and mass spectrometry based methods were developed to analyze nitromethane-based and racing gasoline fuels. Total Vaporization Headspace gas chromatography mass spectrometry (TV-HS-GC/MS) was used to quatitate the amount of methanol in nitromethane fuels to verify that the methanol content was at least 10% (v/v). Total vaporization solid phase microextraction gas chromatography mass spectrometry (TV-SPME-GC/MS) was used to qualitatively identify racing gasoline components, which included isopentane, isooctane, toluene, and tetraethyllead.
Classification Strategies for Fusing UV/visible Absorbance and Fluorescence Microspectrophotometry Spectra from Textile Fibers
(Cambridge UP, 2018-08) Fuenffinger, Nathan; Goodpaster, John V.; Bartick, Edward G.; Morgan, Stephen L.; Chemistry and Chemical Biology, School of Science
A Comprehensive Study of the Alteration of Ignitable Liquids by Weathering and Microbial Degradation
(Wiley, 2018-01) Turner, Dee A.; Williams, Mary; Sigman, Michael A.; Goodpaster, John V.; Chemistry and Chemical Biology, School of Science
The differing effects of weathering and microbial degradation are described here in a comprehensive study that involved 50 different ignitable liquids from the Ignitable Liquids Database and Reference Collection. Examples of ignitable liquid residues from each of the main classes established by the American Society of Testing and Materials are presented. Weathering was accomplished via evaporation, whereas microbial degradation was carried out on soil at room temperature for periods of up to 21 days. Major trends included the rapid degradation of long n-alkanes and monosubstituted alkyl benzenes (e.g., toluene, ethylbenzene, and propylbenzene). Surprisingly, some longer branched alkanes (e.g., trimethyloctanes) were also susceptible to microbial attack. Although all ignitable liquids examined suffered at least to some extent from microbial degradation, gasoline, petroleum distillates, and oxygenates were the most susceptible. Isoparaffinic and naphthenic–paraffinic products were the most resistant to microbial degradation.
Detection of prohibited treatment products on racing tires using headspace solid phase microextraction (SPME) and gas chromatography/ mass spectrometry (GC/MS)
(Royal Society of Chemistry, 2016-01) Kranz, William D.; Carroll, Clinton J.; Goodpaster, John V.; Department of Chemistry & Chemical Biology, School of Science
A variety of commercial tire treatments are available that purport to help automobile tires better cling to the surface of a road or racetrack, raising concerns in the professional racing community that such products might be used to illicitly boost performance in competitive events. These tire treatments are reputed to cut lap times and improve handling and maneuverability. In some cases, the manufacturers even boast that their products are “undetectable” (i.e., impervious to the scrutiny of laboratory testing). In this study, a number of banned tire treatment products were evaluated principally by gas chromatography-mass spectrometry (GC-MS) using solid phase microextraction (SPME) as a pre-concentration technique. The chemicals off-gassed by each product were determined and grouped into two broad categories: ‘plasticizer-based’ tire treatment products and ‘hydrocarbon-based’ tire treatment products. This information was then applied to the analysis of genuine tire samples provided by the United States Auto Club (USAC), a professional racing association. Over the course of one year, 10 out of the 71 questioned samples tested positive for a prohibited treatment product. The manufacturers' claims regarding their products' invisibility to lab tests were largely proven to be unfounded: both the products themselves and the tires treated with them can be identified by a number of characteristic volatile compounds. These included known plasticizers such as pentanedioic acid diethyl ester, plasticizer-related compounds such as 2-ethyl-1-hexanol, and dearomatized distillates.
Differentiation of Structurally Similar Phenethylamines via Gas Chromatography - Vacuum Ultraviolet Spectroscopy (GC – VUV)
(Elsevier, 2019-08) Roberson, Zackery R.; Goodpaster, John V.; Chemistry and Chemical Biology, School of Science
The vacuum ultraviolet region includes wavelengths shorter than 200 nm. Electronic transitions of sigma and pi bonds lie in this region, which have the potential to yield structural information. Thus, a VUV detector should be able to detect nearly any molecule analyzable by gas chromatography. This study sought to determine the extent to which structurally similar phenethylamines are differentiated using their VUV spectra. Phenethylamines are a common drug class including pseudoephedrine and illicit drugs such as methamphetamine. Several phenethylamines are difficult to analyze by electron impact mass spectrometry due to their fragmentation giving the same mass to charge ratio fragments at similar ratios. While phenethylamines are generally differentiable by retention time, an extra layer of specificity is preferred in forensic analyses. A vacuum ultraviolet (VUV) spectrophotometer coupled to a gas chromatograph was used to collect VUV spectra at high frequency between 125 and 430 nm. Eight phenethylamines were analyzed for this work using GC/VUV. A calibration curve and limit of detection study was performed that indicates a limit of detection around 10 μg mL−1 and an upper limit of linearity around 1000 μg mL−1. The spectra, analyzed by Principal Component Analysis and Discriminant Analysis, indicate the ability to reliably differentiate each of the drugs from one another including structural isomers and diastereomers. Lastly, five “street” samples containing amphetamines were analyzed to demonstrate “real world” performance.
Endothelial disruptive proinflammatory effects of nicotine and e-cigarette vapor exposures
(American Physiological Society, 2015-07-15) Schweitzer, Kelly S.; Chen, Steven X.; Law, Sarah; Van Demark, Mary; Poirier, Christophe; Justice, Matthew J.; Hubbard, Walter C.; Kim, Elena S.; Lai, Xianyin; Wang, Mu; Kranz, William D.; Carroll, Clinton J.; Ray, Bruce D.; Bittman, Robert; Goodpaster, John V.; Petrache, Irina; Department of Biochemistry & Molecular Biology, IU School of Medicine
The increased use of inhaled nicotine via e-cigarettes has unknown risks to lung health. Having previously shown that cigarette smoke (CS) extract disrupts the lung microvasculature barrier function by endothelial cell activation and cytoskeletal rearrangement, we investigated the contribution of nicotine in CS or e-cigarettes (e-Cig) to lung endothelial injury. Primary lung microvascular endothelial cells were exposed to nicotine, e-Cig solution, or condensed e-Cig vapor (1-20 mM nicotine) or to nicotine-free CS extract or e-Cig solutions. Compared with nicotine-containing extract, nicotine free-CS extract (10-20%) caused significantly less endothelial permeability as measured with electric cell-substrate impedance sensing. Nicotine exposures triggered dose-dependent loss of endothelial barrier in cultured cell monolayers and rapidly increased lung inflammation and oxidative stress in mice. The endothelial barrier disruptive effects were associated with increased intracellular ceramides, p38 MAPK activation, and myosin light chain (MLC) phosphorylation, and was critically mediated by Rho-activated kinase via inhibition of MLC-phosphatase unit MYPT1. Although nicotine at sufficient concentrations to cause endothelial barrier loss did not trigger cell necrosis, it markedly inhibited cell proliferation. Augmentation of sphingosine-1-phosphate (S1P) signaling via S1P1 improved both endothelial cell proliferation and barrier function during nicotine exposures. Nicotine-independent effects of e-Cig solutions were noted, which may be attributable to acrolein, detected along with propylene glycol, glycerol, and nicotine by NMR, mass spectrometry, and gas chromatography, in both e-Cig solutions and vapor. These results suggest that soluble components of e-Cig, including nicotine, cause dose-dependent loss of lung endothelial barrier function, which is associated with oxidative stress and brisk inflammation.
Enhancing Nonfouling and Sensitivity of Surface-Enhanced Raman Scattering Substrates for Potent Drug Analysis in Blood Plasma via Fabrication of a Flexible Plasmonic Patch
(ACS, 2021-01) Masterson, Adrianna N.; Hati, Sumon; Ren, Greta; Liyanage, Thakshila; Manicke, Nicholas E.; Goodpaster, John V.; Sardar, Rajesh; Chemistry and Chemical Biology, School of Science
Surface-enhanced Raman scattering (SERS) is an ultrasensitive analytical technique, which is capable of providing high specificity; thus, it can be used for toxicological drug assay (detection and quantification). However, SERS-based drug analysis directly in human biofluids requires mitigation of fouling and nonspecificity effects that commonly appeared from unwanted adsorption of endogenous biomolecules present in biofluids (e.g., blood plasma and serum) onto the SERS substrate. Here, we report a bottom-up fabrication strategy to prepare ultrasensitive SERS substrates, first, by functionalizing chemically synthesized gold triangular nanoprisms (Au TNPs) with poly(ethylene glycol)-thiolate in the solid state to avoid protein fouling and second, by generating flexible plasmonic patches to enhance SERS sensitivity via the formation of high-intensity electromagnetic hot spots. Poly(ethylene glycol)-thiolate-functionalized Au TNPs in the form of flexible plasmonic patches show a twofold-improved signal-to-noise ratio in comparison to triethylamine (TEA)-passivated Au TNPs. Furthermore, the plasmonic patch displays a SERS enhancement factor of 4.5 ×107. Utilizing the Langmuir adsorption model, we determine the adsorption constant of drugs for two different surface ligands and observe that the drug molecules display stronger affinity for poly(ethylene glycol) ligands than TEA. Our density functional theory calculations unequivocally support the interaction between drug molecules and poly(ethylene glycol) moieties. Furthermore, the universality of the plasmonic patch for SERS-based drug detection is demonstrated for cocaine, JWH-018, and opioids (fentanyl, despropionyl fentanyl, and heroin) and binary mixture (trace amount of fentanyl in heroin) analyses. We demonstrate the applicability of flexible plasmonic patches for the selective assay of fentanyl at picogram/milliliter concentration levels from drug-of-abuse patients’ blood plasma. The fentanyl concentration calculated in the patients’ blood plasma from SERS analysis is in excellent agreement with the values determined using the paper spray ionization mass spectrometry technique. We believe that the flexible plasmonic patch fabrication strategy would be widely applicable to any plasmonic nanostructure for SERS-based chemical sensing for clinical toxicology and therapeutic drug monitoring.

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