Journal Article

<sup>1</sup>H NMR Spectroscopy and GC-MS Analysis of α-Chioralose. Application to Two Poisoning Cases

Sandrine Savin, Bernard Cartigny, Nathalie Azaroual, Luc Humbert, Michel Imbenotte, Djamel Tsouria, Gaston Vermeersch and Michel Lhermitte

in Journal of Analytical Toxicology

Volume 27, issue 3, pages 156-161
Published in print April 2003 | ISSN: 0146-4760
Published online April 2003 | e-ISSN: 1945-2403 | DOI:
1H NMR Spectroscopy and GC-MS Analysis of α-Chioralose. Application to Two Poisoning Cases

More Like This

Show all results sharing these subjects:

  • Medical Toxicology
  • Toxicology (Non-medical)


Show Summary Details


α-Chloralose, a compound widely used as a rodenticide and in the control of bird pests, is readily available. Two cases of intentional poisoning are reported. Both patients became comatose and presented hypersialorrhea and myoclonal crises in the legs. They were discharged from hospital after several days. As clinical signs of α-chloralose poisoning lack specificity, anamnesis might be difficult, particularly in the case of delayed diagnosis. Toxicological analysis is therefore critical, and this article reports the investigation of serum and urine samples by gas chromatography-mass spectrometry (GC-MS) in the electronimpact mode, and by 1H nuclear magnetic resonance (1H NMR) spectroscopy. Non-hydrolyzed urinary samples and those hydrolyzed by β-glucuronidase were taken into consideration. After acetylation, GC-MS analysis was based on characteristic mass-to-charge ratio values of 272 for α-chloralose and 206 for β-hydroxyethyltheophylline, which was used as internal standard. Characterization of α-chloralose species by 1H NMR spectroscopy was performed taking two parameters into account: chemical shift and coupling-constant values. Without any pretreatment, 1H NMR spectroscopy revealed the presence of free (5.50 and 6.15 ppm) and conjugated forms of α-chloralose by characteristic resonances of H1 and chloral-type protons, respectively. Quantitative analysis was performed by relative integration of peak areas. Serum α-chloralose showed concentrations below the quantitation limit of both methods. In urine samples, the free chemical species rapidly decreased. GC-MS analysis revealed the predominence of conjugation after a β-glucuronidase hydrolysis step. 1H NMR analysis directly showed that on admission of the first patient, average urinary concentrations were 1.73 mmol/L (535 mg/L) for the free form and 13.72 and 6.25 mmol/I, for the two conjugated forms. A later enzymatic treatment confirmed the total concentration of α-chloralose chemical species. Analysis of α-chloralose in urine by either GC-MS or 1H NMR spectroscopy methods proved to be comparable.

Journal Article.  0 words. 

Subjects: Medical Toxicology ; Toxicology (Non-medical)

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.