Publications by authors named "Jonathan Danaceau"

Supercritical fluid chromatography-mass spectrometry (SFC-MS) has proved to be a beneficial tool for sample analysis for a wide variety of compounds and, as such, has recently gained the attention of the anti-doping community. We have tested the applicability of SFC-MS for routine doping control analysing approximately 3 × 1000 identical anti-doping samples utilising SFC-MS instruments from three different vendors: Agilent Technologies, Waters Corporation and Shimadzu Corporation. A 'dilute and inject' approach either without or after hydrolysis of glucuronide metabolites was applied.

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The opioid crisis is linked to an increased misuse of fentanyl as well as fentanyl analogs that originate from the illicit drug market. Much of our current understanding of fentanyl and fentanyl analog use in our communities comes from postmortem toxicology findings. In the clinical settings of addiction medicine and pain management, where the opioid abuse potential is high, the use of fentanyl, as well as specific fentanyl analogs, may be underestimated due to limited plasma testing and limited availability of assays with suitable analytical sensitivity and selectivity to detect misuse of fentanyls.

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Background: This Research article investigates the impact of phospholipid removal and high-performance liquid chromatography column particle size on the accuracy of determining the relative abundance of human metabolites using mass spectrometry peak areas in the context of assessing metabolite abundance for Metabolites in Safety Testing assessment. RESULTS/METHODOLOGY: Plasma samples spiked with 20 compounds, representing ten pairs of drugs and metabolites, were prepared using phospholipid removal plates (Ostro™) or standard protein precipitation techniques and analyzed by liquid chromatography-tandem mass spectrometry using high-performance liquid chromatography columns containing either 2.5 or 3.

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Purpose: Multiple studies have shown that adherence to adjuvant hormonal therapy in women with breast cancer is suboptimal. Measurements of compliance with self-report, pill counts, and/or pharmacy records are susceptible to bias. We assessed the feasibility of using a urine anastrozole assay as an objective biomarker of nonadherence to anastrozole treatment.

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Background: Hydrophilic interaction chromatography (HILIC) is becoming an increasingly popular alternative to traditional reversed-phase chromatography for the analysis of polar compounds. The ability to retain the most polar compounds in HILIC makes it attractive for the analysis of certain large groups of compounds, such as monoamines, which are inherently very polar.

Results: This paper details the development of a HILIC LC-MS/MS method for the analysis of monoamine neurotransmitters.

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Described herein are two general screening procedures for the simultaneous determination of 49 exogenous compounds (21 diuretics, 19 beta-blockers, eight stimulants and two steroidal drugs) in human urine by high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) and ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Urine samples were extracted using a simple and robust solid phase extraction (SPE) method. Samples were injected onto reversed phase HPLC and UPLC columns connected to tandem mass spectrometers capable of scan-to-scan polarity switching.

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Testosterone (T) is the primary male sex hormone. In addition to the development of secondary sex characteristics, testosterone has anabolic effects including increases in muscle size and strength and increases in lean body mass, making it an attractive candidate to enhance athletic performance. In the case of exogenous administration of testosterone, the ratio of testosterone to its isomer, epitestosterone (E), is elevated.

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Previously, the laboratory evaluations of six point-of-collection oral fluid (POC-OF) drug testing devices were reported. Four additional devices, Oralstat (American Bio Medica); SmartClip (Envitec); Impact (LifePoint); and OraLine IV s.a.

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Previous studies using phenylethylamine psychostimulants such as amphetamine (AMPH) have demonstrated that pretreatment with a high-dose of drug followed by a low-dose challenge injection (3 h later) results in an exaggerated behavioral response. In order to explore the mechanism of this exaggerated or what has been suggested to be a "sensitized" response, we investigated the effects of methamphetamine (METH) in a similar treatment paradigm. The current study found that, as suggested by previous studies, a low-dose challenge with METH substantially increased the locomotor response in animals that received a high-dose pretreatment (3.

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Methamphetamine is a highly addictive and potent stimulant, the use of which has increased significantly in recent years. In addition to the severe behavioral and societal consequences associated with methamphetamine abuse, methamphetamine can cause persistent damage to monoaminergic nerve terminals in rats, as measured by either monoamine concentrations or activity of the rate limiting synthetic enzymes, tyrosine hydroxylase and tryptophan hydroxylase. Repeated, sub-neurotoxic doses of methamphetamine, however, can cause rats to become resistant to the neurotoxic effects of multiple high-dose administrations of methamphetamine; a phenomenon known as tolerance.

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This paper describes a high-performance liquid chromatographic-tandem mass spectrometric (HPLC-MS-MS) method for the determination of serotonin (5-HT) and the related indoles tryptophan (TRP), 5-hydroxyindoleacetic acid (5-HIAA), indole-3-acetic acid (IAA), and indole-3-proprionic acid (IPA) in whole blood. Ionization was achieved by atmospheric pressure chemical ionization (APCI). The method uses a solvent gradient to achieve baseline separation of all analytes.

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