Umbilical Cord Tissue: From Antemortem Monitoring to Postmortem Possibilities.

ABSTRACT: Umbilical cord tissue (UCT) traditionally has been used as an antemortem matrix for identifying and monitoring fetal exposure to drugs suspected to have been used during pregnancy. The specimen offers several advantages as a testable tissue, including accessibility and ease of collection, ample sample volume, a long window of detection, and ability to detect for a wide range of drugs. Despite these advantages, little to no research exists on the use of UCT as a postmortem forensic toxicology specimen. This article aims to provide insights into UCT toxicological testing and infer potential applications for postmortem use, such as investigations into stillbirths and infant abandonment. Umbilical cord tissue offers several benefits as a postmortem toxicological specimen. Importantly, it can be collected with or without an autopsy being performed and may help explain factors that contribute to the underdevelopment and death of the neonate. With the limited sample volumes present in infant investigations, toxicological analysis of UCT could become a valuable tool for neonatal medicolegal death investigations.

Analysis of umbilical cord tissue as an indicator of in utero exposure to toxic adulterating substances.

In utero drug exposure is a significant public health threat to the well-being and normal development of the neonate. Recently, testing of umbilical cord tissue (UCT) has been employed to measure illicit drug exposure, as drugs used by the mother during the third trimester may be retained in the UCT. Focus has also been given to potential adverse health effects among drug users, resulting from exposure to pharmacologically active adulterants and cutting agents in the street drug supply. The in utero effects of these substances have not been well studied in humans, nor has their presence been demonstrated as a means for assessing adverse health effects in the neonate. Here, we describe the application of a novel test method to analyze UCT for the presence of more than 20 common adulterating/cutting substances via LC/Q-TOF. In total, 300 de-identified UCT samples were analyzed-all had previously tested positive for cocaine or opiates. Generally, the positivity rates of individual compounds were similar between the Cocaine and Opiates Subgroups, apart from levamisole, xylazine, dipyrone (metabolites), and promethazine. Many of the adulterants used in the street drug supply do have legitimate medicinal/therapeutic uses, including several of the compounds most frequently detected in this study. Caffeine and lidocaine were the most frequently identified compounds both individually (>70% each) and in combination with each other. Alternatively, levamisole, an adulterant with no legitimate therapeutic use, was present in 12% of cases. Importantly, this data demonstrates that the detection of traditional drugs of abuse may serve as indicators of potential in utero exposure to toxic adulterating substances during gestation. While there is cause for concern with respect to any unintentional drug exposure, illicit drug use during pregnancy, including uncontrolled dosing, poly-adulterant consumption, and the interactions of these drug mixtures, produces a significant public health threat to the neonate which warrants further study.

Determination of Cross-Reactivity of Contemporary Cannabinoids with THC Direct Immunoassay (ELISA) in Whole Blood.

Immunoassay procedures, such as enzyme-linked immunosorbent assay (ELISA), are widely used for screening samples in both driving under the influence of drugs (DUID) and postmortem (PM) investigations. While these are sensitive and widely used techniques, they lack specificity compared to more novel instrumental screening platforms. In this study, the cross-reactivities of several cannabinoid isomers and related compounds were evaluated in whole blood using the Cannabinoids Direct ELISA kit from Immunalysis. The compounds of interest were supplemented individually at three different concentrations, ranging from 10 to 100 ng/mL or 10 to 1,000 ng/mL depending on analyte, to determine initial feasibility. Compounds exhibiting cross-reactivity were then tested to create dose-response curves to calculate the percent cross-reactivity. The cross-reactivity was determined to be 200% for delta-8-carboxy-tetrahydrocannabinol (THC) (delta-8-carboxy-THC), 25% for delta-9,11-THC, 13% for delta-10-THC, 7% for delta-6a(10a)-THC, 3% for THC-O-acetate and 0.5% for tetrahydrocannabiphorol. To determine potential impacts on forensic laboratory casework, a review of DUID and PM casework was also performed. From November 2020 to June 2021, a random sampling of DUID and PM cases was selected monthly and evaluated for the presence of cannabinoid isomer(s) in the absence of a reportable delta-9-carboxy-THC result. While validated techniques for the identification and confirmation of these isomer(s) did not exist at the time of routine testing, delta-8-carboxy-THC was believed to be the most common isomer finding based on current testing capability. This study demonstrated a noticeable increase in the presence of isomeric cannabinoid compounds in both forensic DUID and PM casework sampled during this period and suggests potential impacts for clinical casework as well.

Levamisole-a Toxic Adulterant in Illicit Drug Preparations: a Review.

ABSTRACT: Discovered in the 1960s, the common anthelminthic levamisole has seen widespread use in veterinary applications. Its use rapidly expanded thereafter to include human medical treatments for a variety of acute and chronic disorders. Because of reports of severe adverse effects, the US Food and Drug Administration withdrew levamisole's approval for human use in 2000; however, medical options outside the United States and illicit options worldwide allow continued accessibility to levamisole. The compound is rapidly metabolized in the body, with at least 2 known active metabolites. Levamisole has a broad range of immunomodulatory effects, including both stimulatory and inhibitory effects on immune responses. It is generally well tolerated at therapeutic concentrations, although a variety of autoimmune-related adverse effects have been reported, including agranulocytosis, leukopenia, purpura, and visible necrotized skin tissue. Individuals with levamisole-compromised immune systems are more susceptible to infections, including COVID-19. Since the early 2000's, levamisole has been frequently used as an adulterating agent in illicit street drugs, especially cocaine, fentanyl, and heroin. Although its prevalence has varied over time and geographically, levamisole has been detected in up to 79% of the street supply of cocaine at levels up to 74% by weight. Its presence in illicit drug markets also raises concern over the potential for exposure of children and neonates, although this is supported by only limited anecdotal evidence. Levamisole is not currently included in routine drug testing panels, although a variety of confirmatory testing techniques exist across a range of antemortem and postmortem specimen options. Because of its varying presence in illicit drug markets, both the medical and forensic communities need to be aware of levamisole and its potential impact on toxicological investigations.

Orthogonal patterning of multiple biomolecules using an organic fluorinated resist and imprint lithography.

The ability to spatially deposit multiple biomolecules onto a single surface with high-resolution while retaining biomolecule stability and integrity is critical to the development of micro- and nanoscale biodevices. While conventional lithographic patterning methods are attractive for this application, they typically require the use of UV exposure and/or harsh solvents and imaging materials, which may be damaging to fragile biomolecules. Here, we report the development of a new patterning process based on a fluorinated patterning material that is soluble in hydrofluoroether solvents, which we show to be benign to biomolecules, including proteins and DNA. We demonstrate the implementation of these materials into an orthogonal processing system for patterning multibiomolecule arrays by imprint lithography at room temperature. We further showcase this method's capacity for fabricating patterns of receptor-specific ligands for fundamental cell studies.