The use and abuse of fentanyl has risen drastically over the last several decades. The abuse of this substance has created a hazardous situation for law enforcement and first responders because they could arrive at locations and not necessarily know that they will encounter fentanyl or a fentanly analog. Fentanyl analogs are substances that have a similar structure to fentanyl, and while the analogs may have additional or altered groups on the molecule, the backbone structure remains the similar. This work focuses on the electrochemical characterization of fentanyl as a stepping stone for the detection of both fentanyl and later fentanyl analogs by electrochemistry. The metabolic reaction of fentanyl is an N-dealkylation to norfentanyl, occurring in the liver, and can be mimicked by electrochemistry through the irreversible oxidation of fentanyl. This electrochemical reaction is hypothesized to generate electroactive metabolites in solution. The combination of the visualization of both the irreversible oxidation with the development of the additional metabolic redox peaks would constitute a unique electrochemical signiture for fentanyl and fentanyl analogs towards a universal rapid screening assay. The electrochemical behavior of fentanyl was characterized in depth using multiple electrochemical techniques such as cyclic voltammetry (CV), square wave voltammetry (SWV), and differential pulse voltammetry (DPV). The optimization of the supporting electrolyte, the potential range, and methods to decrease the background current were explored with CV. To work toward a more portable system, screen printed electrodes were used. The observation of the metabolic peaks remained challenging, and different methods were attempted to achieve it. The quantification of fentanyl was successfully demonstrated using the different electrochemical systems proposed in this work. The electrochemical characterization of fentanyl and the optimization of multiple experimental parameters were the first step in developing a universal, rapid, electrochemical sensing method for the detection of fentanyl and fentanyl analogs. <br>

Indiana University-Purdue University Indianapolis (IUPUI) / The use and abuse of fentanyl has risen drastically over the last several decades. The abuse of this substance has created a hazardous situation for law enforcement and first responders because they could arrive at locations and not necessarily know that they will encounter fentanyl or a fentanyl analog. Fentanyl analogs are substances that have a similar structure to fentanyl, and while the analogs may have additional or altered groups on the molecule, the backbone structure remains similar. This work focus on the electrochemical characterization of fentanyl as a stepping stone for the detection of both fentanyl and later fentanyl analogs by electrochemistry. The metabolic reaction of fentanyl is an N-dealkylation to norfentanyl, occurring in the liver, and can be mimicked by electrochemistry through the irreversible oxidation of fentanyl. This electrochemical reaction is hypothesized to generate electroactive metabolites in solution. The combination of the visualization of both the irreversible oxidation with the development of the additional metabolic electrochemical peaks would constitute a unique electrochemical signature for fentanyl and fentanyl analogs towards a universal rapid screening assay. The electrochemical behavior of fentanyl was characterized in depth using multiple electrochemical techniques such as cyclic voltammetry (CV), square wave voltammetry (SWV) and differential pulse voltammetry (DPV). The optimization of the supporting electrolyte, the potential range, and methods to decrease the background current were explored with CV. To work towards a more portable system, screen printed electrodes were used. The observation of the metabolic peaks remained challenging, and different methods were attempted to achieve it. The quantification of fentanyl was successfully demonstrated using the different electrochemical systems proposed in this work. The electrochemical characterization of fentanyl and the optimization of multiple experimental parameters were the first step in developing a universal, rapid, electrochemical sensing method for the detection of fentanyl and fentanyl analogs. / 2023-02-28

<p>  </p> <p>Nationwide use of illicit drugs has continued to rise over the last few decades, with more than a two-fold increase in global seizures from 2016 and 2020. Most seized drug samples are complex mixtures of drugs and cutting agents, which can complicate the detection and quantification of the illicit drugs in the sample. The presence of these cutting agents can however be beneficial for source tracing purposes, as the majority of cutting agents are selected based on availability in the area where the bulk drug was prepared. The goal of this work was to conduct a systematic study of the electrochemical characteristics of the most common cutting agents found in illicit drugs using unmodified, commercially available glassy carbon electrodes. The long-term goal is to establish an extensive database of electrochemical characterizations of cutting agents and illicit drugs encountered by law enforcement using unmodified, commercially available electrodes to help expand the developing field of forensic electrochemical analyses. This database could then be referenced for the identification of unknown samples to determine the presence of possible illicit drugs and cutting agents that are present to help guide the analyst in further testing.</p> <p>The standard methods for drug detection include a combination of laboratory testing and field-deployable assays ranging from colorimetric tests to gas chromatography-mass spectrometry instrumentation. These detection methods, as well as relevant literature were investigated in Chapter 1. The most used screening methods for illicit drugs are colorimetric tests; however, these assays are prone to false positives. Chapter 1 introduces the existing applications and current research efforts in forensic electrochemistry by describing relevant electrochemical sensors and methods and examining in particular their performance regarding accuracy, sensitivity, and low-cost claims. This overview highlights the broad possibilities of electrochemical analysis in forensics as well as the opportunities when applied to detection and quantification of illicit drugs, demonstrating the current needs for more systematic and consistent characterizations of cutting agents found in seized-drug samples. Chapter 2 details the material, reagents, and experimental conditions, showing their simplicity, and the standard electrochemical and preparative equipment used geared towards an easy implementation in any analytical laboratory. Chapter 3 describes the systematic voltametric characterizations performed on thirteen common cutting agents: phenacetin hydrochloride, levamisole hydrochloride, diphenhydramine hydrochloride, quinine, acetaminophen, ascorbic acid, caffeine, lactose, inositol, mannitol, glucose, sodium bicarbonate and calcium carbonate. In addition to the common, information-rich cyclic voltammetry (CV), differential pulse voltammetry (DPV) and square wave voltammetry (SWV) were used as these pulsed electroanalytical methods are typically considered more sensitive than CV and often employed for quantitative analyses of species present at low concentrations (Chapter 3). Overall, DPV resulted in voltammograms with peaks shaped closer to the ideal redox peaks, also referred to as ‘better defined’, thus enhancing the analytical performance of the assay. For example, In the analysis of diphenhydramine hydrochloride, DPV permitted the measurement of an oxidation with a peak displayed at 1.0 V vs Ag/AgCl, which was not observable when performing CV or SWV. On the other hand, SWV provided noticeably greater intensities of peak current, which allowed for a better detection of the difficult-to-observe redox reactions of quinine occurring at -0.4, 0.0 and 0.4 V vs Ag/AgCl.</p> <p>Some chemical species when present in seized drugs can alter the pH of the tested samples, such as ascorbic acid. Changes in pH will impact the redox activity of the pH-dependent electroactive species present in a sample, thus we investigated how pH of the solvent affected the observation of the redox peaks of those susceptible cutting agents, namely ascorbic acid, quinine, diphenhydramine hydrochloride, and levamisole hydrochloride (Chapter 4). Of particular interest was a significant change in the electrochemical characterization of these species when the pH was varied around their pKa values. Additionally, the composition of the solvent, or supporting electrolyte (SE) solution, can in some cases result in interactions with the analytes in the sample; the study of caffeine with different SE in Chapter 4 illustrates this situation. Specifically, sulfuric acid was the most suited SE of those tested for caffeine analysis.</p> <p>The impact of successive voltametric scans, on the analysis of chemical species were also investigated, using acetaminophen and quinine, demonstrating the development of additional redox peaks in some situations that could provide additional elements towards a more individualized electrochemical profile for cutting agents (Chapter 4). </p> <p>The influence of the material of the working electrode on the electrochemical characterization of cutting agents was explored. Solutions of ascorbic acid, acetaminophen, quinine, and diphenhydramine hydrochloride were electrochemically characterized using a glassy carbon and a platinum working electrode, while ascorbic acid was also characterized on gold and silver electrodes. These examples demonstrate the adaptability of this electroanalytical method with various commonly used electrodes. (Chapter 4). In Chapter 5, we applied similar electrochemical method to the identification of cutting agents and illicit drugs in two-component mixtures. Specifically, these trials included mixtures of fentanyl with a cutting agent at a relative ratio of 1 : 100, using as cutting agents ascorbic acid, diphenhydramine hydrochloride, or glucose, demonstrating the ability of this simple electrochemical method using common commercial electrodes to simultaneously detect illicit drugs and cutting agents. </p>

<p dir="ltr">Gas chromatography-mass spectrometry (GC-MS) is a frequently used technique in forensic chemistry for the identification of controlled substances and explosives. GC-MS can be coupled with solid-phase microextraction (SPME), in which a fiber with a sorptive coating is placed into the headspace above a sample or directly immersed in a liquid sample. Analytes are adsorbed onto the fiber which is then placed inside the heated GC inlet for desorption.</p><p dir="ltr">Illicit drugs are often found in the form of impure solids, mixed with other drugs, adulterants, and diluents. A simple method for the quick identification of drugs including methamphetamine, cocaine, heroin, fentanyl, and pharmaceutical tablets was developed. Headspace SPME methods were utilized with an elevated extraction temperature for the detection of various drugs in powder and tablet form. An extraction temperature of 120°C was used to encourage analytes into the headspace of the vial. A sample of the solid drug was placed in a headspace vial with no prior sample preparation or clean-up. This vial was then heated inside of an agitator where the sample was extracted. It was found that drugs in solid and tablet form can be detected using this high temperature headspace SPME method at the temperature of 120°C with no prior sample preparation. This method is simple, efficient, and cost effective for the detection of legal and illicit drugs in solid form.</p><p dir="ltr">Headspace SPME may also be used for the analysis of explosive materials. Canines trained at detecting hidden explosives should be trained using real explosive materials that have minimal contamination by other explosive odors to ensure accurate identification of potential threats. Therefore, the potential for cross-contamination between training aids is of importance. There are various storage methods in use by canine handlers such as plastic and cloth bags, but these can lead to cross-contamination between training aids during storage. Alternatively, odor-permeable membrane devices (OPMDs) may store training aides and be used as a delivery device. A membrane in the OPMD allows for volatile compounds from the training aids to be released during training while helping to prevent contaminants from entering the device. OPMDs were used in addition to traditional storage containers to monitor the contamination and degradation of 14 explosives used as canine training aids. Samples included explosives that contain highly volatile compounds like dynamite and explosives with less volatile compounds like RDX. Explosives were stored individually using traditional storage bags or inside of an OPMD at two locations, IUPUI and an Indianapolis Metropolitan Police Department. The police department actively used the training aids during canine trainings. Samples from each storage type at both locations were collected at 0, 3, 6, and 9 months and analyzed using Fourier transform infrared (FTIR) spectroscopy and GC-MS with SPME. FTIR analyses showed no signs of degradation of the training aids from any timepoint or location. GC-MS identified cross-contamination from ethylene glycol dinitrate and/or 2,3-dimethyl-2,3-dinitrobutane across almost all samples regardless of storage condition. The contamination was found to be higher among training aids that were stored in traditional ways and were in active use by canine teams. Additionally, Time 0 had the highest level of contamination, indicating that explosive training aids are received from the vendors with initial cross-contamination.</p><p dir="ltr">To test the initial cross-contamination levels of training aids, 11 explosive materials were ordered from three different vendors. A 1-gram sample of each was collected and analyzed using SPME with GC-MS. In several cases, explosive materials that are commercially available already exhibit elevated levels of contamination. This indicates that training aids must be acquiring contamination during manufacturing and/or storage at the vendor facility. The cross-contamination of explosive canine training aids stored in OPMDs was further evaluated and compared to traditional storage methods. This was done by storing various combinations of storage containers such as cloth bags, velcro bags, and OPMDs along with explosives and using activated charcoal strips to collect the volatile compounds such as 2,3-dimethyl-2,3-dinitrobutane and ethylene glycol dinitrate. Only one type of storage container, a velcro bag, showed evidence of contamination, indicating that OPMDs may not further prevent cross-contamination of explosive training aids.</p>

Human scent, or the volatile organic compounds (VOCs) produced by an individual, has been recognized as a biometric measurement because of the distinct variations in both the presence and abundance of these VOCs between individuals. In forensic science, human scent has been used as a form of associative evidence by linking a suspect to a scene/object through the use of human scent discriminating canines. The scent most often collected and used with these specially trained canines is from the hands because a majority of the evidence collected is likely to have been handled by the suspect. However, the scents from other biological specimens, especially those that are likely to be present at scenes of violent crimes, have yet to be explored. Hair, fingernails and saliva are examples of these types of specimens. In this work, a headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) technique was used for the identification of VOCs from hand odor, hair, fingernails and saliva. Sixty individuals were sampled and the profiles of the extracted VOCs were evaluated to assess whether they could be used for distinguishing individuals. Preliminary analysis of the biological specimens collected from an individual (intra-subject) showed that, though these materials have some VOCs in common, their overall chemical profile is different for each specimen type. Pair-wise comparisons, using Spearman Rank correlations, were made between the chemical profiles obtained from each subject, per a specimen type. Greater than 98.8% of the collected samples were distinguished from the subjects for all of the specimen types, demonstrating that these specimens can be used for distinguishing individuals. Additionally, field trials were performed to determine the utility of these specimens as scent sources for human scent discriminating canines. Three trials were conducted to evaluate hair, fingernails and saliva in comparison to hand odor, which was considered the standard source of human odor. It was revealed that canines perform similarly to these alternative human scent sources as they do to hand odor implying that, though there are differences in the chemical profiles released by these specimens, they can still be used for the discrimination of individuals by trained canines.

While ketamine is traditionally administered for anesthesia or pain management, illicit usage is often seen in forensic cases either as a recreational drug or as a tool in drug-facilitated sexual assault. Xylazine is an anesthetic agent used in veterinary medicine and does not have FDA approval for use in humans. However, it has recently been observed as a cutting agent in heroin. Post-mortem specimens present many challenges when it comes to toxicological analysis. Due to compound degradation and decomposition factors, analytes present at trace levels may be missed in blood and urine. Hair, bone, and insects have recently been investigated as alternative matrices for postmortem analysis due to their increased durability compared to more traditional matrices. However, this durability increases the difficulties in extracting and isolating compounds of interest from these matrices via traditional extraction and chromatography methods. These methods require lengthy extraction times and extensive cleanup steps in order to obtain samples suitable for analysis. Utilizing multiple instrumentation combinations, analysts are able to detect compounds at trace levels. Through the use of multidimensional chromatography, several time-consuming extraction steps can be eliminated while still retaining the ability of trace level detection and quantitation. Using Waters Oasis® HLB PRiME solid phase extraction cartridges using a methanol pH10 loading and an acetonitrile pH3 elution, a solvent extraction yielded linear dynamic ranges of 2pg/mL-1ng/mL and 5pg/mL-1ng/mL for xylazine and ketamine respectively. Rat specimens utilized in this project were treated as per an Institutional Animal Care and Use Committee (IACUC) protocol. The test rodents received an acute dosage of 2mg/mL of xylazine and 24mg/mL of ketamine approximately half an hour prior to death. The 14 test samples were placed outside directly on the ground at the Boston University Forensic Anthropology Outdoor Research Facility (Holliston, MA, U.S.A.) for a period of 6 months. A 15th rat was kept in -20°C until analysis to serve as a Time=0 sample. The outdoor samples were recovered and de-fleshed along with the Time=0 sample manually. Drug-free hair samples were donated anonymously as per Internal Review Board (IRB) protocols.

<p> Illicit drug abuse is a widespread issue in the United States and worldwide. Many methods  seek to ease the analytical workload required to collect, analyze, and identify these drugs. Paper  spray-mass spectrometry (PS-MS) is one response to this analytical workload as it offers a rapid,  affordable, and simple means for drug identification by mass spectrometry. This work centers on  the use of pressure-sensitive adhesive (PSA) lined paper as a PS-MS substrate for drug recovery  and detection. The use of PSA paper as a sampling and analysis substrate has been previously  established but is expanded herein with new capabilities and applications. Chapter 2 introduces  the combination of color tests followed by PS-MS for presumptive and confirmatory drug  identification. Three color tests (cobalt thiocyanate, Simon, or Marquis) were performed on the  PSA paper with subsequent drug confirmation occurring by PS-MS. Chapter 3 examines the use  of PSA paper and PS-MS for the recovery and detection of fentanyl, fentanyl precursors, and  analogs from shipping-related surfaces and in the presence of high amounts of cutting agents. The  use of a cartridge that accommodates a full-sized PSA paper ticket was also explored for drug  detection. Chapter 4 assesses PS-MS with PSA paper on portable MS instrumentation. Analyte  recovery and carryover as well as instrument robustness were evaluated. The color test and PS-MS protocol examined in Chapter 2 was also successfully applied to a portable MS instrument.  Application of PS-MS to the portable system highlights the potential fieldability of the technique. </p>

<p>Paper spray mass spectrometry (PS-MS) is an ambient ionization technique that has been proven useful in many types of investigative analyses. However, the use of this technique with regards to environmental samples has been largely unexplored since the technique’s development. In this work, paper spray mass spectrometry was utilized to detect and quantify compounds for environmental, forensic and chemical defense applications. Due to the sensitive nature of some projects, the work was split into two volumes. Volume 1 focuses on the detection of pharmaceuticals in soil using paper spray (Chapter 2) and the detection of chemical warfare agent (CWA) simulants and CWA hydrolysis products (Chapter 3). Volume 2 focuses on the detection and quantitation of fentanyl analogs in environmental matrices. Chapter 5 focuses on the rapid analysis of fentanyl analogs in soil matrices. The following chapter evaluates the ability of PS-MS to detect low concentrations of fentanyl analogs in water (Chapter 6). Throughout this work, paper spray has proven to be an effective, rapid alternative to chromatography for the analysis of environmental samples. </p>

<p>  </p> <p>With bombings in the United States on the rise for the first time since 2016, the detection and identification of explosives remains of pertinent interest to law enforcement agencies. This work presents two soon-to-be published research articles that focus on the detection and identification of explosives by both chemical instrumentation and canines. The first article, <em>Quantitative Analysis of Smokeless Powder Particles in Post-Blast Debris via Gas Chromatography/Vacuum Ultraviolet Spectroscopy (GC/VUV)</em>, utilizes gas chromatography/vacuum ultraviolet spectroscopy (GC/VUV) to determine the difference in chemical composition of two smokeless powders in both pre- and post-blast conditions. The compounds of interest in this study were nitroglycerin, 2,4-dinitrotoluene, diphenylamine, ethyl centralite, and di-n-butyl phthalate. Concentration changes between pre- and post-blast smokeless powder particles were determined as well as microscopic differences between pre- and post-blast debris for both smokeless powders in all devices. To our knowledge, this is the first use of GC/VUV for the quantification of explosives. The second article, <em>An Odor-Permeable Membrane Device for the Storage of Canine Training Aids</em>, proposes the use of an odor-permeable membrane device (OPMD) as a standardized storage method for canine training aids. It is hypothesized that the OPMD would minimize cross-contamination between training aids, and that the OPMD could be used for canine training as well as storage. The goal of this research is to use flux and evaporation rate to quantify the explosive odor that escapes from the OPMD compared to unconfined explosives. Preliminary data suggests that there is an exponential relationship between relative boiling point and evaporation rate. It has been determined that compounds with higher boiling points have lower evaporation rates than compounds that have lower boiling points. The materials studied thus far are known odor compounds produced by explosive formulations. These include nitromethane, nitroethane, 1-nitropropane, r-limonene, and toluene. </p>

A ciência forense moderna caminha lado a lado com a pesquisa científica. Os cientistas forenses se deparam diariamente com vários casos que requerem a análise de resíduos provenientes de disparos de arma de fogo (gunshot residues - GSR). Este trabalho contempla o desenvolvimento de uma metodologia para determinar assinaturas químicas de disparos de arma de fogo, medindo-se as concentrações de Pb, Ba e Sb presentes nos resíduos provenientes destes disparos depositados nas proximidades do orifício de entrada de projéteis, baseada na técnica de espectrometria de massas de alta resolução com fonte de plasma indutivamente acoplado (ICP-MS). Foram realizados disparos em cinco tipos de tecidos-alvos e coletados testemunhos em regiões próximas ao orifício de entrada dos projéteis. Os resultados demonstraram que o método possibilitou identificar e distinguir os resíduos de revólver calibre .38 ao de pistolas calibres .40 e 9 mm. O uso de gráficos ternários como ferramenta de análise dos dados coletados, permitiu identificar padrões específicos de distribuição de amostras em branco e dos resíduos depositados após disparos de revólveres e pistolas. A metodologia possibilitou a atribuição da origem dos disparos por meio de confirmação dos resíduos coletados também das mãos dos atiradores. Como conseqüência a metodologia representa um grande avanço nos procedimentos da polícia e visa adicionar uma contribuição valiosa às investigações forenses. / The modern forensic science goes hand in hand with scientific research. The forensic scientists are faced every day with many cases requiring the analysis of residues from firing gun (gunshot residues GSR). This works describes the development of a methodology to determine chemical signatures of shots from a firearm, by measuring the concentrations of Pb, Ba e Sb in the residues from these shots deposited near the entrance hole of bullets, based on the technique with high resolution inductively coupled plasma mass spectrometry (HRICP-MS). Shots were performed on five types of target-fabrics and collected testimonies from regions close to the entrance hole of projectiles. The results showed that the method enabled us to identify and distinguish the residues of the .38 caliber revolver and pistols .40 and 9mm caliber. The use of ternary graphs as a tool for data analysis helped to identify specific patterns of distribution of blank samples and gunshot residues deposited after firing revolvers and pistols. The methodology enabled the assignment of the origin of the shot through the confirmation of the residues collected also from the hands of shooters. As a result the methodology in police procedures and aims to add a valuable contribution to forensic investigations.