Gill, Chris

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Now showing 1 - 5 of 49
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    Carfentanil structural analogs found in street drugs by paper spray mass spectrometry and their characterization by high-resolution mass spectrometry
    (John Wiley & Sons, 2023-05) Borden, Scott A.; Mercer, Savannah R.; Saatchi, Armin; Wong, Ernest; Stefan, Cristiana M.; Wiebe, Heather; Hore, Dennis K.; Wallace, Bruce; Gill, Chris G.
    Carfentanil is one of the most potent synthetic opioids ever developed, with an estimated analgesic potency approximately 20–100 times that of fentanyl and 10,000 times that of morphine. Carfentanil has been appearing in the illicit drug supply in many regions and has been linked to fatal overdose events. A subset of 59 street drug samples obtained in Victoria, B.C., that were confirmed to contain carfentanil were analyzed by mass spectrometry for this study. Carfentanil quantitation by paper spray mass spectrometry ranged from 0.05 to 2.95 w/w% (median = 0.32%) in the original drug sample. Paper spray mass spectrometry analysis also detected two unknown peaks at m/z 380.2 and 381.2 in 31 of these 59 samples (53%). Initial tandem mass spectrometry experiments revealed structural similarities between these unknown compounds and carfentanil, suggesting they were potential structural analogs, possibly arising from incomplete purification during synthesis. High-resolution mass spectrometry determined the chemical formulas of these compounds as C23H29N3O2 (m/z 380.2333) and C23H29N2O3 (m/z 381.2137). Literature and tandem mass spectrometry results were used to determine the identity of these potential new psychoactive substances, C23H29N3O2 as desmethylcarfentanil amide and C23H29N2O3 as desmethylcarfentanil acid. μ-Opioid receptor binding modeling determined that the binding poses of these analogs were nearly identical to that of carfentanil with relative binding energy calculations of 0.544 kJ/mol (desmethylcarfentanil amide) and −0.171 kJ/mol (desmethylcarfentanil acid); these data suggest they may share the toxic effects of carfentanil and have similar potencies.
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    Beyond a spec: Assessing heterogeneity in the unregulated opioid supply
    (BioMed Central, 2024-03-15) Gozdzialski, Lea; Louw, Rebecca; Kielty, Collin; Margolese, Ava; Poarch, Eric; Sherman, Miriam; Cameron, Fred; Gill, Chris G.; Wallace, Bruce; Hore, Dennis
    This study assesses the consequence of drug heterogeneity and sampling of consumer level opioid purchased in Victoria, British Columbia (n=21, 50–100 mg each) on quantitative fentanyl results determined from testing with paper spray mass spectrometry. This study found that the variability in fentanyl concentration from drug heterogeneity and sampling is greater than that attributed to the analytical technique. On a practical level, this provides data to help guide communication of limitations of drug checking services, supporting the aim of trust and transparency between services and people who use drugs. However, if drug checking services continue to be restricted from fully engaging with the reality of manufacturing, buying, selling, mixing and dosing practices, the accuracy, usefulness, and impact will always be limited.
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    Therapeutic drug monitoring of clozapine in human serum by high-throughput paper spray mass spectrometry
    (Elsevier, 2024-02-22) Saatchi, Armin; Zarkovic, Taelor M.; Borden, Scott A.; Palaty, Jan; Gill, Chris G.
    This study aimed to assess the viability of a PS-MS method for the rapid measurement of clozapine and norclozapine in human serum samples as an alternative to liquid chromatography mass spectrometry (LC-MS).
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    A state-of-the-science review of alcoholic beverages and polycyclic aromatic hydrocarbons
    (EHP Publishing, 2024-01-19) King, Liam; Aplin, Rebekah; Gill, Chris G.; Naimi, Timothy
    Background: The association between alcohol and certain cancers is well established, yet beyond ethanol and its metabolite acetaldehyde, little is known about the presence of other carcinogenic compounds in alcoholic beverages, including polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene (a Group I carcinogen). Objectives: We summarized the published literature on PAH levels in alcoholic beverages to identify potential gaps in knowledge to inform future research. Methods: Medline and Scopus were searched for primary research published from January 1966 to November 2023 that quantified PAH levels among various types of alcoholic beverages, including whisky, rum, brandy, gin, vodka, wine, and beer. Studies that were not primary literature were excluded; only studies that quantified PAH content in the specified alcoholic beverages were included. Results: Ten studies published from 1966 to 2019 met the criteria for review. Other than beverage type, no publication reported selection criteria for their samples of tested alcohol products. Studies used a variety of analytical methods to detect PAHs. Of the 10 studies, 7 were published after 2000, and 6 assessed products. Of the studies, 7 examined spirits; 3, beer; and 4, wines. Benzo[a]pyrene was most prevalent among spirit products, particularly whisky, with values generally exceeding acceptable levels for drinking water. Some beer and wine products also contained PAHs, albeit at lower levels and less frequently than spirit products. Discussion: PAHs are found in some alcohol products and appear to vary by beverage type. However, there is an incomplete understanding of their presence and levels among large, representative samples from the range of currently available alcohol products. Addressing this gap could improve understanding of alcohol–cancer relationships and may have important implications for public health and the regulation of alcohol products. In addition, novel methods, such as direct mass spectroscopy, may facilitate more thorough testing of samples to further investigate this relationship.
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    A strategy for the detection of benzodiazepine drugs using low-resolution paper-spray mass spectrometry for harm reduction drug checking
    (John Wiley & Sons, 2023-12-25) Miskulin, Allie; Wallace, Bruce; Gill, Chris G.; Hore, Dennis
    The ability to detect newly emerging substances is of great importance in reducing harms for people who use drugs. New psychoactive substances including novel benzodiazepines in the illicit drug supply have been linked to high rates of overdose deaths while complicating drug checking as an overdose prevention strategy. Paper-spray mass spectrometry (PS-MS) has emerged as a novel strategy to rapidly detect trace components in street drug samples. While targeted, low-resolution PS-MS methods have proven effective, newly emerging substances are often missed. To address this, a method was applied to low-resolution full-scan PS-MS data to aid in the early detection and identification of novel benzodiazepines in the unregulated drug supply. Using the developed method, true positives rates of 0.89 and 0.75 were achieved for bromazolam and etizolam in street samples obtained in a community drug checking service. The applicability of the method was further demonstrated for a novel benzodiazepine, desalkylgidazepam, that has recently emerged in the illicit drug supply.