An Automated Method for the Determination of Trimebutine and N-Mono-Desmethyl Trimebutine by On-Line Turbulent Flow Coupled with Liquid Chromatography-Tandem Mass Spectrometry in Human Plasma: Application to a Fatal Poisoning Case with Toxicokinetic Study.

A liquid chromatography-MS-MS turbulent flow on-line extraction method was developed for the determination of trimebutine (TMB) and its main active metabolite N-mono-desmethyltrimebutine (nortrimebutine or nor-TMB) in human plasma. After protein precipitation and internal standard (IS, haloperidol-d4) addition, 50 µL of the supernatant were transferred onto a Cyclone-Turbo-Flow extraction column followed by an Hypersil PFP Gold analytical column. Detection was carried out on a triple quadrupole tandem mass spectrometer using positive electrospray ionization. The transitions used were m/z 388.0→343.0, 374.0→195.0 and 380.1→169.0 for TMB, nor-TMB and IS, respectively. The method was validated over the concentration range of 10-1,000 ng/mL for both compounds. The accuracy evaluated at three concentrations was within 90.0-98.5% and the intra- and interday coefficient of variation's for the two molecules were <8.7%. The method was applied to a toxicokinetic study of a self-poisoning case with TMB in a 19-old girl. The concentration of TMB decreased from 747 to 77 ng/mL, while nor-TMB decreased from 9,745 to 205 ng/mL after 5 days and the fatal issue. This case confirms the literature underlining the potential toxicity of TMB, which has long time been considered as a harmless molecule.

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.

Fatal intoxication with labetalol (Trandate).

The dead body of a 44-year-old woman, previously known for depression and alcoholism, has been discovered at her place of residence by her husband. A forensic autopsy has been carried out. The results indicated unspecific histological lesions (alveolar oedema, liver steatosis and interstitial nephritis) but did not reveal any apparent cause of death. Several boxes of medicines have been found near the body, justifying a toxicological analysis. This has been performed on peripheral blood and urine samples using liquid chromatography with diode array and mass spectrometric detections, in conjunction with gas chromatography coupled with mass spectrometry. Ethanol has been found (1.24 g/L in blood, 2.63 g/L in urine and 1.33 g/kg in gastric content), as well as therapeutic concentrations of meprobamate (14.1mg/L) and low concentrations of nordazepam (0.12 mg/L) in blood. On the other hand, particularly high levels of labetalol, a widely used beta-blocker, have been found both in blood (1.7 mg/L) and urine (20.2mg/L), which led us to measure labetalol levels in available viscera samples (liver, heart, kidney, and lung) and gastric content. Measured concentrations were 14.2 microg/g, 7.8 microg/g, 5.4 microg/g, 5.2 microg/g and 31.1 microg/g, respectively. We describe here the first report of a fatal intoxication attributed to labetalol that is linked to its acute toxicity, with tissue distribution of this beta-blocker.