Enantioselective extraction of (+)-(S)-citalopram and its main metabolites using a tailor-made stir bar chiral imprinted polymer for their LC-ESI-MS/MS quantitation in urine samples

• Published in: Talanta (Oxford) Vol. 116; pp. 448 - 453
• Main Authors: Unceta, Nora, Gómez-Caballero, Alberto, García, Deiene, Díaz, Goretti, Guerreiro, Antonio, Piletsky, Sergey, Aránzazu Goicolea, M., Barrio, Ramón J.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15-11-2013
• Subjects: Adsorption; Antidepressive Agents, Second-Generation - urine; Chromatography, Liquid; Citalopram - analogs & derivatives; Citalopram - urine; enantiomers; Humans; ion exchange chromatography; LC-ESI-ITMS; mass spectrometry; metabolites; Molecular Imprinting - methods; polymers; Polymers - chemistry; Reference Standards; S-citalopram; S-desmethylcitalopram; S-didesmethylcitalopram: chiral imprinted polymer (CIP)-coated stir bar; Sensitivity and Specificity; Solid Phase Extraction - methods; Solid Phase Extraction - standards; Spectrometry, Mass, Electrospray Ionization; Stereoisomerism; Tandem Mass Spectrometry; Urine; LC-ESI-ITMS; Urine; S-didesmethylcitalopram: chiral imprinted polymer (CIP)-coated stir bar; S-citalopram; S-desmethylcitalopram
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2013.07.004

This paper reports the application of a chiral imprinted polymer (CIP)-coated stir bar for the selective extraction of (+)-(S)-citalopram (SCIT) and its main metabolites, (+)-(S)-desmethylcitalopram (SDCIT) and (+)-(S)-didesmethylcitalopram (SDDCIT), from urine samples. The developed device has been demonstrated to be capable of selectively extracting the three target analytes from urine samples without saturating the imprinted sites. A CIP-coated stir bar sorptive extraction procedure (CIP-SBSE) is proposed for the isolation of SCIT, SDCIT and SDDCIT followed by their subsequent analysis using liquid chromatography ion trap mass spectrometry (LC-ITMS). Deuterated SCIT-d6 was used as an internal standard. The method was validated using a standard procedure, which revealed that a quantification of 5ngmL−1 was obtained in urine samples and that the accuracy and precision were within the established values while no matrix effect was observed.
•A chiral MIP-SBSE device for S-citalopram and its main metabolites are developed.•A LC-ITMS method is established for the determination of these analytes.•The validated method (CIP-SBSE/LC-ITMS) is used in urine samples.