An automated method for measurement of methoxetamine in human plasma by use of turbulent flow on-line extraction coupled with liquid chromatography and mass spectrometric detection.

Methoxetamine is a new ketamine derivative designer drug which has recently become available via the Internet marketed as "legal ketamine". It is a new dissociative recreational drug, acting as an NMDA receptor antagonist and dopamine reuptake inhibitor. The objective of this study was to develop on-line automated sample preparation using a TurboFlow device coupled with liquid chromatography with ion-trap mass spectrometric detection for measurement of methoxetamine in human plasma. Samples (100 µL) were vortex mixed with internal standard solution (ketamine-d4 in acetonitrile). After centrifugation, 20 µL of the supernatant was injected on to a 50 mm × 0.5-mm C18XL Turboflow column. The retained analytes were then back-flushed on to a 50 mm × 3-mm (3 µm) Hypersil Gold analytical column for chromatographic separation, then eluted with a formate buffer-acetonitrile gradient. Methoxetamine and the IS were ionized by electrospray in positive mode. Parent [M + H](+) ions were m/z 248.1 for methoxetamine and m/z 242.0 for the IS. The most intense product ions from methoxetamine (m/z 203.0) and the IS (m/z 224.0) were used for quantification. The assay was accurate (96.8-108.8% range) and precise (intra and inter-day coefficients of variation <8.8%) over the range of 2.0 (lower limit of quantification) to 1000.0 ng mL(-1) (upper limit of quantification). No matrix effect was observed. This method has been successfully applied to determination of plasma concentrations of methoxetamine in the first French hospitalization case report after acute intoxication; the plasma concentration was 136 ng mL(-1).

Measurement of atropine and scopolamine in hair by LC-MS/MS after Datura stramonium chronic exposure.

BACKGROUND: Datura stramonium is an herbaceous annual plant. All parts of the plant contain tropane alkaloids such as atropine and scopolamine. We report the case of a 22-year-old man admitted to a general hospital for visual and aural hallucinations. One week after his admission, as the hallucinations remained, the patient was transferred to a psychiatric hospital. Neither blood nor urine was conserved during his hospitalization, so a hair analysis was requested in order to identify a possible consumption of a Datura seed infusion. METHODS: After decontamination and washing, hair strands were segmented into four pieces and grinded into a fine and homogeneous powder. We then incubated 20 mg for 10 min in 1 mL of phosphate buffer at pH 5.0 in the presence of 100 ng of ketamine-d4, used as internal standard (IS). Liquid-liquid extraction was performed with 4 mL of a mixture of hexane/ethyl acetate (1/1, v/v). The residue was reconstituted in 80 µL of mobile phase. A further 10 µL were injected into an 1.9 µm Hypersil GOLD PFP column (100 mm×2.1 mm) eluted with a gradient of acetonitrile and 2 mmol/L 0.1% formate buffer at a flow rate of 300 µL/min. Compounds were detected by a LCQ TSQ Vantage XP triple-quadripole mass spectrometer equipped with an electrospray ionization (ESI) source set in positive mode. SRM transitions m/z 290.2→124.1, m/z 304.2→138.1, and m/z 242.1→129.1 were optimized for atropine, scopolamine and IS, respectively. RESULTS: The assay was accurate and precise over the range of 1.0 (lower limit of quantification) to 1000.0 pg/mg (upper limit of quantification) in hair. Both atropine (from 8.4 to 15.0 pg/mg) and scopolamine (1.0-1.3 pg/mg) were identified in the four segment of the hair showing a regular consumption of Datura admitted by the patient himself. CONCLUSION: We report here the first description of atropine with scopolamine in a Caucasian dark man's hair after D. stramonium chronic exposure, using a validated LC-MS/MS method.