An exploratory view into allelic drop-out of sequenced autosomal STRs.

As massively parallel sequencing is implemented in forensic genetics, an understanding of sequence data must accompany these advancements, that is, accurate modeling of data for proper statistical analysis. Allelic drop-out, a common stochastic effect seen in genetic data, is often modeled in statistical analysis of STR results. This proof-of-concept study sequenced several serial dilutions of a standard sample ranging from 4 ng to 7.

Characterization of fentanyl HCl powder prior to and after systematic degradation.

Fentanyl HCl is of particular interest in forensic cases but there is a notable gap in literature regarding its analysis. This study utilized a multi-method approach to characterize fentanyl HCl powder, both fresh and following a forced degradation process. Using sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) and direct injection gas chromatography-mass spectrometry (GC-MS), five compounds were identified in fresh fentanyl HCl powder.

Cannabinoid distribution in fatally-injured pilots' postmortem fluids and tissues.

The primary psychoactive component of cannabis, Δ-tetrahydrocannabinol (THC) impairs cognitive function and psychomotor performance, particularly for complex tasks like piloting an aircraft. The Federal Aviation Administration's (FAA) Forensic Sciences Section at the Civil Aerospace Medical Institute (Oklahoma City, OK) performs toxicological analyses on pilots fatally injured in general aviation incidents, permitting cannabinoids measurement in a broad array of postmortem biological specimens. Cannabinoid concentrations in postmortem fluids and tissues from 10 pilots involved in airplane crashes are presented.

Identification and quantification of cannabinoids in postmortem fluids and tissues by liquid chromatography-tandem mass spectrometry.

Cannabis sativa is commonly used worldwide and is frequently detected by forensic laboratories working with biological specimens from potentially impaired drivers or pilots. To address the problem of limited published methods for cannabinoids quantification in postmortem specimens, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to quantify Δ-tetrahydrocannabinol (THC), 11-hydroxy-THC (11-OH-THC), 11-nor-9-carboxy-THC (THCCOOH), 8β,11-dihydroxy-THC (8β-diOH-THC), 8β-hydroxy-THC (8β-OH-THC), THC-glucuronide (THC-g), THCCOOH-glucuronide (THCCOOH-g), cannabidiol (CBD), cannabinol (CBN), cannabigerol (CBG), Δ-tetrahydrocannabivarin (THCV), and 11-nor-9-carboxy-THCV (THCVCOOH). Solid phase extraction concentrated analytes prior to analysis on a biphenyl column coupled to a mass spectrometer in electrospray positive ionization mode using multiple reaction monitoring.

Cannabinoids in Oral Fluid: Limiting Potential Sources of Cannabidiol Conversion to Δ9- and Δ8-Tetrahydrocannabinol.

In late 2019, the National Laboratory Certification Program (NLCP) published an article reporting on the potential analytical conversion of 7-carboxy cannabidiol (CBD-COOH) to 11-nor-9-carboxy-Δ9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in urine samples. The same conversion is possible in oral fluid with the parent analyte cannabidiol (CBD) converting to Δ9-tetrahydrocannabinol (Δ9-THC) and Δ8-tetrahydrocannabinol (Δ8-THC) under strong acidic conditions. With the recent rise in states legalizing the use of THC and the availability of products containing only CBD, unless the analytical in vitro conversions are controlled, the detection of Δ9-THC or Δ8-THC in oral fluid may not clarify whether the donor was using a CBD product or licit or illicit THC product.

Surface Contamination Generated by "One-Pot" Methamphetamine Production.

Methamphetamine production is the most common form of illicit drug manufacture in the United States. The "one-pot" method is the most prevalent methamphetamine synthesis method and is a modified Birch reduction, reducing pseudoephedrine with lithium and ammonia gas generated . This research examined the amount of methamphetamine surface contamination generated by one-pot syntheses or "cooks", as well as the effectiveness of hosing with water as a simplified decontamination technique, to assess associated public health and environmental consequences.

An optimized method for sample collection, extraction, and analysis of fentanyl and fentanyl analogs from a non-porous surface.

Illicit use of the potent opioid fentanyl and its analogs (fentanyls) are on the rise in the United States. As use increases, drug production tends to also increase, leading to more locations being contaminated with the potentially lethal substance. Because fentanyl-contaminated locations may present a risk to the general public, a method for sampling, identifying, and quantitating these fentanyls from surfaces is in need.

Postmortem Fluid and Tissue Concentrations of THC, 11-OH-THC and THC-COOH.

Marijuana is the most commonly abused illicit drug worldwide. Marijuana is used for its euphoric and relaxing properties. However, marijuana use has been shown to result in impaired memory, cognitive skills and psychomotor function.

Evaluation of Oral Fluid as a Specimen for DUID.

Drugged driving has become more prevalent than drunk driving and is quickly gaining national attention due to increased prescription drug abuse and recent cannabis legalization. Unlike alcohol, police officers do not generally have access to approved devices to screen for drugs at the roadside. Onsite drug screening devices do exist and are used in other countries, but have not garnered widespread approval for use in the United States in driving under the influence of drugs (DUID) cases.

The quantitation of cocaine on U.S. currency: survey and significance of the levels of contamination.

It has long been suspected that the illicit distribution of cocaine in the United States has led to a large-scale contamination of the currency supply. To investigate the extent of contamination, 418 currency samples (4174 bills) were collected from 90 locations around the United States from 1993 to 2009. The extent of their cocaine contamination was quantitated via gas chromatography/mass spectrometry or liquid chromatography/mass spectrometry.

Simultaneous quantification of vinblastine and desacetylvinblastine concentrations in canine plasma and urine samples using LC-APCI-MS/MS.

A highly sensitive and specific liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (LC/APCI-MS/MS) method has been developed and validated for simultaneous quantification of vinblastine and its metabolite, desacetylvinblastine, in canine plasma and urine samples. Plasma and urine samples were processed by a solid phase extraction procedure. The optimal chromatographic behavior of these analytes was achieved on pentafluorophenyl (PFP) propyl analytical column (5μm, 50×2.

Oxidative stress and mitochondrial-mediated apoptosis in dopaminergic cells exposed to methylcyclopentadienyl manganese tricarbonyl.

Methylcyclopentadienyl manganese tricarbonyl (MMT), an organic manganese-containing gasoline additive, was investigated to determine whether MMT potentially causes dopaminergic neurotoxic effects. MMT is acutely cytotoxic and dopamine-producing cells (PC-12) seemed to be more susceptible to cytotoxic effects than nondopaminergic cells (striatal gamma-aminobutyric acidergic and cerebellar granule cells). MMT also potently depleted dopamine apparently by cytoplasmic vesicular release to the cytosol, a neurochemical change resembling other dopaminergic neurotoxicants.