Analytical and Bioanalytical Chemistry

, Volume 400, Issue 10, pp 3517–3525 | Cite as

Enantioselective analysis of zopiclone and its metabolites in plasma by liquid chromatography/tandem mass spectrometry

  • Milena Araújo Tonon
  • Valquíria A. P. Jabor
  • Pierina Sueli Bonato
Original Paper


A high-performance liquid chromatographic method with triple-quadrupole mass spectrometry detection (LC-MS-MS) was developed and validated for the first time for the simultaneous quantification of zopiclone and its metabolites in rat plasma samples. The analytes were isolated from rat plasma by liquid–liquid extraction and separated using a chiral stationary phase based on an amylose derivative, Chiralpak ADR-H column, and ethanol–methanol–acetonitrile (50:45:5, v/v/v) plus 0.025% diethylamine as the mobile phase, at a flow-rate of 1.0 mL min−1. Moclobemide was used as the internal standard. The developed method was linear over the concentration range of 7.5–500 ng mL−1. The mean absolute recoveries were 74.6 and 75.7; 61.6 and 56.9; 72.5, and 70.7 for zopiclone enantiomers, for N-desmethyl zopiclone enantiomers and for zopiclone-N-oxide enantiomers, respectively, and 75.9 for the internal standard. Precision and accuracy were within acceptable levels of confidence (<15%). The method application in a pilot study of zopiclone kinetic disposition in rats showed that the levels of (+)-(S)-zopiclone were always higher than those of (−)-R-zopiclone. Higher concentrations were also observed for (+)-(S)-N-desmethyl zopiclone and (+)-(S)-N-oxide zopiclone, confirming the stereoselective disposition of zopiclone.


Zopiclone LC-MS-MS Metabolites Kinetic disposition 



The authors gratefully acknowledge Conselho Nacional de Desenvolvimento Científico e Tecnológico and Fundação de Amparo à Pesquisa do Estado de São Paulo for financial support and for granting research fellowships.


  1. 1.
    Mistri HN, Jangid AG, Pudage A, Shrivastav P (2008) J Chromatogr B 864:137–148CrossRefGoogle Scholar
  2. 2.
    Wessell AM, Weart CW (2005) Am Fam Physician 71:2359–2360Google Scholar
  3. 3.
    Piperaki S, Parissi-Poulou M (1996) J Chromatogr A 729:19–28CrossRefGoogle Scholar
  4. 4.
    Fernandez C, Alet P, Davrinche C, Adrien J, Thuillier A, Farinotti R, Gimenez F (2002) J Pharm Pharmacol 54:335–340CrossRefGoogle Scholar
  5. 5.
    Fernandez C, Gimenez F, Baune B, Maradeix V, Thuillier A, Farinotti R (1993) J Chromatogr 617:271–278CrossRefGoogle Scholar
  6. 6.
    Fernandez C, Baune B, Gimenez F, Thuillier A, Farinotti R (1991) J Chromatogr 572:195–202CrossRefGoogle Scholar
  7. 7.
    Foster RT, Caillé G, Ngoc AH, Lemko CH, Kherani R, Pasutto FM (1994) J Chromatogr B 658:161–166CrossRefGoogle Scholar
  8. 8.
    Hempel G, Blaschke G (1996) J Chromatogr B 675:139–146CrossRefGoogle Scholar
  9. 9.
    Fernandez C, Maradeix V, Gimenez F, Thuillier A, Farinotti R (1993) Drug Metab Dispos 21:1125–1128Google Scholar
  10. 10.
    Tornio A, Neuvonen PJ, Backman JT (2006) Eur J Clin Pharmacol 62:645–651CrossRefGoogle Scholar
  11. 11.
    Guidance for industry: bioanalytical method validation (2001) FDA, Accessed 10 Jan 2011
  12. 12.
    Fernandez C, Gimenez F, Mayrargue J, Thuillier A, Farinotti R (1995) Chirality 7:267–271CrossRefGoogle Scholar
  13. 13.
    Mannaert E, Daenens P (1996) J Pharm Biomed Anal 14:1367–1370CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Milena Araújo Tonon
    • 1
  • Valquíria A. P. Jabor
    • 1
  • Pierina Sueli Bonato
    • 1
  1. 1.Department of Physics and Chemistry, Faculty of Pharmaceutical Sciences of Ribeirão PretoUniversity of São PauloRibeirão PretoBrazil

Personalised recommendations