Determination of antidepressants in whole blood using hollow-fiber liquid-phase microextraction and gas chromatography-mass spectrometry

Author(s)

dos Santos, Marcelo Filonzi ^[1] ; Ferri, Caio Caleiras ^[1] ; Seulin, Saskia Carolina ^[2] ; Leyton, Vilma ^[2] ; Goncalves Pasqualucci, Carlos Augusto ^[3] ; Munoz, Daniel Romero ^[2] ; Yonamine, Mauricio ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Pharmaceut Sci, BR-05508000 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Fac Med, BR-05508000 Sao Paulo - Brazil

^[3] Univ Sao Paulo, Death Verificat Serv, BR-05508000 Sao Paulo - Brazil

• Document type: Journal article
• Source: Forensic Toxicology; v. 32, n. 2, p. 214-224, AUG 2014.
• Web of Science Citations: 14

Abstract

A hollow-fiber liquid-phase microextraction (HF-LPME), used in three-phase mode, and combined with gas chromatography-mass spectrometry (GC-MS), was developed to quantify antidepressants and their major metabolites (amitriptyline, nortriptyline, imipramine, desipramine, clomipramine, desmethylclomipramine, fluoxetine, and norfluoxetine) in whole blood samples, using their deuterated analogs as internal standards. The HF-LPME system comprised a disposable 8-cm polypropylene porous hollow fiber, 4.0 ml of sample solution (0.5 ml of blood added to 3.5 ml of 0.1 M NaOH: donor phase), dodecane (organic phase), and 0.1 M formic acid (acceptor phase) for extraction. After stirring the system, the acceptor phase was evaporated under a nitrogen stream and resuspended in 30 mu l of methanol. Derivatization was not required. A 2.0-mu l aliquot of this solution was injected into a GC-MS system. The method was validated after the optimization of several parameters that may influence the extraction efficiency. The limits of quantification for all antidepressants were below the therapeutic levels (20.0 ng/ml). The average intraday and interday precisions were within 9.7 and 9.8 %, respectively, for all analytes. The calibration curves were linear in the concentration range of 20-1,200 ng/ml. The developed method was applied to seven actual postmortem samples. Tricyclic antidepressants were detected in all of the analyzed cases. To our knowledge, this is the first demonstration of usefulness of HF-LPME for analysis of antidepressants in postmortem forensic cases. (AU)

• FAPESP's process: 09/08314-9 - Postmortem redistribution of psychoactive substances in human biological tissues
• Grantee: Mauricio Yonamine
• Support Opportunities: Regular Research Grants
• FAPESP's process: 10/06530-3 - Postmortem redistribution of antidepressants and their metabolites in biological tissues
• Grantee: Marcelo Filonzi dos Santos
• Support Opportunities: Scholarships in Brazil - Doctorate