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1.
J Breath Res ; 18(4)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38876091

RESUMO

The Peppermint Initiative, established within the International Association of Breath Research, introduced the peppermint protocol, a breath analysis benchmarking effort designed to address the lack of inter-comparability of outcomes across different breath sampling techniques and analytical platforms. Benchmarking with gas chromatography-ion mobility spectrometry (GC-IMS) using peppermint has been previously reported however, coupling micro-thermal desorption (µTD) to GC-IMS has not yet, been benchmarked for breath analysis. To benchmarkµTD-GC-IMS for breath analysis using the peppermint protocol. Ten healthy participants (4 males and 6 females, aged 20-73 years), were enrolled to give six breath samples into Nalophan bags via a modified peppermint protocol. Breath sampling after peppermint ingestion occurred over 6 h att= 60, 120, 200, 280, and 360 min. The breath samples (120 cm3) were pre-concentrated in theµTD before being transferred into the GC-IMS for detection. Data was processed using VOCal, including background subtractions, peak volume measurements, and room air assessment. During peppermint washout, eucalyptol showed the highest change in concentration levels, followed byα-pinene andß-pinene. The reproducibility of the technique for breath analysis was demonstrated by constructing logarithmic washout curves, with the average linearity coefficient ofR2= 0.99. The time to baseline (benchmark) value for the eucalyptol washout was 1111 min (95% CI: 529-1693 min), obtained by extrapolating the average logarithmic washout curve. The study demonstrated thatµTD-GC-IMS is reproducible and suitable technique for breath analysis, with benchmark values for eucalyptol comparable to the gold standard GC-MS.


Assuntos
Benchmarking , Testes Respiratórios , Mentha piperita , Humanos , Testes Respiratórios/métodos , Testes Respiratórios/instrumentação , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Espectrometria de Mobilidade Iônica/métodos , Espectrometria de Mobilidade Iônica/normas , Adulto Jovem , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa/métodos , Cromatografia Gasosa/instrumentação , Cromatografia Gasosa/normas
2.
Rapid Commun Mass Spectrom ; 37(8): e9487, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36739105

RESUMO

RATIONALE: Post-separation addition of chemical modifiers in liquid chromatography-mass spectrometry is widely used for improving ionization sensitivity and selectivity. This is typically accomplished using a post-column T-junction, which can result in sample dilution and imperfect mixing. We present a passive semi-permeable hollow fiber membrane approach for the addition of chemical modifiers that avoids these issues. METHODS: Model compounds were directly infused by flow injection to an electrospray ionization triple quadrupole mass spectrometer after passing through a polydimethylsiloxane hollow fiber membrane. Ionization enhancement reagents were introduced into the flowing stream by membrane permeation from aqueous solutions. Ionization enhancement from volatile acids and bases in positive and negative electrospray ionization was evaluated to assess the feasibility of this approach. RESULTS: The membrane-based apparatus resulted in relative ionization enhancement factors of up to 14×, depending upon the analyte, reagent, and ionization mode used. Ionization enhancement signal stability is reasonable (relative standard deviation of 5-7%) for extended periods from the same reagent solution, and minimal analyte dilution is observed. A proof-of-concept demonstration of the chromatographic "trifluoroacetic acid fix" strategy is presented. CONCLUSIONS: An on-line mass spectrometry ionization reagent addition method with potential post-chromatography reagent addition applications was developed using a hollow fiber polydimethylsiloxane membrane. This approach offers a promising alternative to traditional methods requiring additional hardware such as pumps and T-junctions that can result in sample dilution and imperfect reagent mixing.

3.
Drug Test Anal ; 15(5): 484-494, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36605020

RESUMO

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 C23 H29 N3 O2 (m/z 380.2333) and C23 H29 N2 O3 (m/z 381.2137). Literature and tandem mass spectrometry results were used to determine the identity of these potential new psychoactive substances, C23 H29 N3 O2 as desmethylcarfentanil amide and C23 H29 N2 O3 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.


Assuntos
Drogas Ilícitas , Fentanila , Analgésicos Opioides , Espectrometria de Massas em Tandem , Amidas
4.
Analyst ; 147(13): 3109-3117, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35708603

RESUMO

A direct mass spectrometry method utilizing reactive paper spray ionization was developed for sensitive cannabinoid quantitation in biofluid matrices. The ca. 2-minute sample measurements used on-paper derivatization to significantly increase paper spray mass spectrometry (PS-MS) positive ion mode sensitivity while minimizing sample preparation steps. Calibrations demonstrate high linearity, with R2 > 0.99 for (-)-trans-Δ9-tetrahydrocannabinol (THC) in oral fluid and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) in urine. The limit of detection and lower limit of quantitation were 0.78 and 10 ng mL-1 for THC in oral fluid and 1.3 and 10 ng mL-1 for THC-COOH in urine, respectively. THC-COOH levels measured by reactive PS-MS in seven spiked human urine samples showed bias of -9.4 to 5.9%, and percent difference values of -16.8 to 9.8% in comparison with a reference LC-MS method. Based upon the method simplicity, validation experiments, sensitivity, and rapidity, we conclude that reactive PS-MS has potential applications for rapid cannabinoid drug testing in urine and oral fluid.


Assuntos
Canabinoides , Dronabinol , Canabinoides/análise , Cromatografia Líquida/métodos , Dronabinol/análise , Humanos , Espectrometria de Massas , Detecção do Abuso de Substâncias/métodos
5.
Drug Alcohol Depend ; 235: 109427, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35405459

RESUMO

BACKGROUND: Drug checking uses analytical chemistry technologies to report on the composition of drugs from the unregulated market to reduce substance use-related risks, while additionally allowing for monitoring and reporting of the supply. In the context of an overdose crisis linked to fentanyl, we used drug checking data to examine variability within the illicit opioid supply. METHODS: In this time-series analysis, data was collected from a drug checking service in Victoria, Canada from November 2020 to July 2021. Drugs reported as opioids by participants of the service (N = 454) were analyzed to determine sample composition and paper spray mass spectroscopy was used to quantify low-concentration actives. Interquartile and statistical process control (SPC) analysis, namely standard deviation control charts, were used to examine the degree of variability among samples. RESULTS: Fentanyl was found in 96% of samples reported to be opioids, with a median concentration of 9%. Concentrations varied significantly, with a standard deviation of 7% for fentanyl and where nearly 20% of data points fell outside the control limits. Over half of the samples contained an additional and unexpected active, most commonly etizolam (43% of samples). Etizolam also showed a large level of variability, uncorrelated to that of fentanyl. CONCLUSIONS: Based on our chemical quantification and SPC analysis, a high degree of variability was found in opioid samples from the unregulated market in both the drugs detected and the concentrations of those drugs. This demonstrated the opioid crisis to be less attributable to a bad batch of drugs but rather the general variability found in the unregulated market.


Assuntos
Analgésicos Opioides , Overdose de Drogas , Analgésicos Opioides/análise , Canadá , Fentanila/análise , Humanos , Espectrometria de Massas
6.
Int J Drug Policy ; 102: 103611, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35151084

RESUMO

BACKGROUND: In British Columbia, Canada, illicit opioids have been increasingly combined with etizolam, a benzodiazepine analog, that continues to challenge popular portable drug checking technologies as it is often present in low concentrations as a result of its high potency. An unknown combination of opioids and benzodiazepines may have dangerous consequences due to unpredictable dosing, increased respiratory depression, and complicated overdose response measures. METHODS: Surface-enhanced Raman spectroscopy (SERS) using a portable Raman spectrometer is used to establish a univariate model for the detection of etizolam in opioid drug mixtures (n=100) obtained from the Vancouver Island Drug Checking Project, where the presence of etizolam has been determined using paper-spray mass spectrometry. Benzodiazepine immunoassay test strips are also performed on all samples for comparison. RESULTS: SERS is shown to detect etizolam with high sensitivity (96%) and specificity (86%). In contrast, benzodiazepine test strips demonstrate a low sensitivity (8%) for the detection of etizolam of the same samples (n=100), with only small improvements when studied over a larger subset of samples (n=506, sensitivity = 29%). CONCLUSION: We have demonstrated the potential of SERS for trace detection of etizolam within complex sample matrices. Since SERS is one of the few portable technologies capable of trace detection, further studies on its ability for quantification and discrimination of trace adulterants in street samples is of significant interest for point-of-care applications.


Assuntos
Analgésicos Opioides , Análise Espectral Raman , Analgésicos Opioides/análise , Benzodiazepinas , Colúmbia Britânica , Diazepam/análogos & derivados , Fentanila/análise , Humanos
7.
Drug Alcohol Rev ; 41(2): 410-418, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34347332

RESUMO

INTRODUCTION: Drug checking services for harm reduction and overdose prevention have been implemented in many jurisdictions as a public health intervention in response to the opioid overdose crisis. This study demonstrates the first on-site use of paper spray mass spectrometry for quantitative drug checking to address the limitations of current on-site drug testing technologies. METHODS: Paper spray mass spectrometry was used to provide on-site drug checking services at a supervised consumption site in the Downtown Eastside of Vancouver, British Columbia, Canada during a 2-day pilot test in August 2019. The method included the targeted quantitative measurement of 49 drugs and an untargeted full scan to assist in identifying unknown/unexpected components. RESULTS: During the pilot, 113 samples were submitted for analysis, with 88 (78%) containing the client expected substance. Fentanyl was detected in 45 of 59 expected fentanyl samples, and in 50 (44%) samples overall at a median concentration of 3.6% (w/w%). The synthetic precursor of fentanyl, 4-anilino-N-phenethyl-piperidine (4-ANPP), was found in 74.0% of all fentanyl samples at a median concentration of 2.2%, suggesting widespread poor manufacturing practices. Etizolam was detected in 10 submitted samples anticipated to be fentanyl at a median concentration of 2.5%. No clients submitting these samples expected etizolam or a benzodiazepine in their sample. In three instances, it was co-measured with fentanyl, and in seven cases it was detected alone. DISCUSSION AND CONCLUSIONS: The quantitative capabilities and low detection limits demonstrated by paper spray mass spectrometry offer distinct benefits over existing on-site drug checking methods and harm reduction services.


Assuntos
Overdose de Drogas , Drogas Ilícitas , Analgésicos Opioides/análise , Colúmbia Britânica , Canadá , Overdose de Drogas/prevenção & controle , Fentanila/análise , Redução do Dano , Humanos , Drogas Ilícitas/análise , Espectrometria de Massas , Projetos Piloto , Tecnologia
8.
Int J Drug Policy ; 97: 103409, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34392112

RESUMO

BACKGROUND: There has been a recent increase in adulteration of opioids with low concentration actives such as fentanyl analogues and benzodiazepines. As drug checking projects using vibrational spectroscopy continue to seek confirmatory lab-based testing, the concern and reality of missing these potentially harmful substances in point-of-care testing is prevalent. METHODS: A portable GC-MS was used to analyze select opioid samples acquired at a drug checking service in Victoria, Canada (n=59). Certified reference standards of several fentanyl analogues and benzodiazepines were measured to guide targeted analysis of these samples. Results were compared with those obtained using a lab-based paper spray mass spectrometer. RESULTS: Portable GC-MS was able to identify 62% of samples containing carfentanil and 36% of samples containing etizolam. In the case of etizolam, the success rate was higher for more potent samples: 78% of etizolam-containing samples were identified when the etizolam concentration was above 3% by weight. In comparison, infrared spectroscopy was able to detect etizolam in only 9% of the etizolam-containing samples, and is not sensitive enough to detect carfentanil at relevant concentrations. CONCLUSIONS: Portable GC-MS has potential in identifying low concentration substances in a point-of-care setting, without relying on subsequent off-site confirmatory testing.


Assuntos
Analgésicos Opioides , Preparações Farmacêuticas , Analgésicos Opioides/análise , Diazepam/análogos & derivados , Fentanila/análogos & derivados , Cromatografia Gasosa-Espectrometria de Massas , Humanos
9.
Mass Spectrom Rev ; 39(5-6): 703-744, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32048319

RESUMO

Mass spectrometry has been the "gold standard" for drugs of abuse (DoA) analysis for many decades because of the selectivity and sensitivity it affords. Recent progress in all aspects of mass spectrometry has seen significant developments in the field of DoA analysis. Mass spectrometry is particularly well suited to address the rapidly proliferating number of very high potency, novel psychoactive substances that are causing an alarming number of fatalities worldwide. This review surveys advancements in the areas of sample preparation, gas and liquid chromatography-mass spectrometry, as well as the rapidly emerging field of ambient ionization mass spectrometry. We have predominantly targeted literature progress over the past ten years and present our outlook for the future. © 2020 Periodicals, Inc. Mass Spec Rev.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Drogas Ilícitas/análise , Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , Cromatografia Líquida/métodos , Medicina Legal/métodos , Humanos , Drogas Ilícitas/isolamento & purificação , Microextração em Fase Líquida , Sensibilidade e Especificidade , Microextração em Fase Sólida
10.
Anal Sci Adv ; 1(2): 97-108, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38715908

RESUMO

Paper spray mass spectrometry is presented as a direct, quantitative tool for the measurement of pharmaceutical drugs and a variety of fentanyl analogs in solid samples and powder slurries with the ultimate goal of providing meaningful harm-reduction drug checking. Method development and validation was carried out for fentanyl analog slurries as a proxy for street drug samples. Lower limits of quantitation were determined to be 3.6-7.4 ng/g for fentanyl analogs in the pharmaceutical slurry matrix. Using 1 mg of solid sample, the method can quantify picogram quantities of these drugs, well below required thresholds for even the most potent fentanyl analogs. Quality control samples were prepared and used to assess method validity according to the Scientific Working Group for Forensic Toxicology (SWGTOX) guidelines. Performance metrics for both precision and accuracy were found to be within SWGTOX-recommended guidelines. Additionally, pharmaceutical tablets were used to demonstrate the applicability of the developed paper spray methodology for the direct qualitative and quantitative analysis of active ingredients in pharmaceutical powders deposited directly onto the paper spray substrate. A proposed workflow for rapid solid drug sample measurements is presented with potential applications for point-of-use street drug measurements and other solid sample matrices.

11.
Anal Bioanal Chem ; 411(2): 291-303, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30470916

RESUMO

Existing mass spectrometric methods for the analysis of fatty acids often require derivatization, chromatographic separations, and/or extensive sample preparation. Direct mass spectrometry strategies can avoid these requirements, but may also suffer from poor quantitation and/or lack of sensitivity. Condensed phase-membrane introduction mass spectrometry (CP-MIMS) provides direct quantitative measurements of analytes in complex samples with little or no sample preparation. CP-MIMS uses a semipermeable membrane to transfer neutral, hydrophobic compounds from real-world samples to a mass spectrometer. The results presented utilize aqueous/organic sample solvent (donor) mixtures to allow for the sensitive (pptr) detection of a range of fatty acids. The relative sensitivity across a homologous series of fatty acids is observed to change, favoring short- or long-chain fatty acids, depending on the amount of miscible co-solvent added to the donor phase. Further, lithium acetate added online via the acceptor phase was used in tandem mass spectrometry experiments to determine the location of double bonds in polyunsaturated fatty acids (PUFAs). The method was applied to direct measurements and structural determinations for selected PUFAs in salmon tissue samples. Standard addition was employed to quantify the amount of PUFAs in a variety of salmon samples, yielding 0.27-0.42 and 0.40-0.84 w/w % for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), respectively, for Sockeye and Chinook salmon, in good agreement with the literature. This work presents, to our knowledge, the first use of CP-MIMS for the direct analysis of fatty acids in oily foodstuff samples. Graphical abstract ᅟ.


Assuntos
Ácidos Graxos/química , Espectrometria de Massas/métodos , Músculo Esquelético/química , Salmão , Animais , Análise de Alimentos/métodos , Metanol , Sensibilidade e Especificidade
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