title: Optimization of ultrasound assisted dispersive liquid-liquid microextraction of six antidepressants in human plasma using experimental design.
abstract: A simple Ultrasounds Assisted-Dispersive Liquid Liquid Microextraction (UA-DLLME) method is presented for the simultaneous determination of six second-generation antidepressants in plasma by Ultra Performance Liquid Chromatography with Photodiode Array Detector (UPLC-PDA). The main factors that potentially affect to DLLME were optimized by a screening design followed by a response surface design and desirability functions. The optimal conditions were 2.5 mL of acetonitrile as dispersant solvent, 0.2 mL of chloroform as extractant solvent, 3 min of ultrasounds stirring and extraction pH 9.8.Under optimized conditions, the UPLC-PDA method showed good separation of antidepressants in 2.5 min and good linearity in the range of 0.02-4 μg mL(-1), with determination coefficients higher than 0.998. The limits of detection were in the range 4-5 ng mL(-1). The method precision (n=5) was evaluated showing relative standard deviations (RSD) lower than 8.1% for all compounds. The average recoveries ranged from 92.5% for fluoxetine to 110% for mirtazapine. The applicability of DLLME/UPLC-PDA was successfully tested in twenty nine plasma samples from antidepressant consumers. Real samples were analyzed by the proposed method and the results were successfully submitted to comparison with those obtained by a Liquid Liquid Extraction-Gas Chromatography - Mass Spectrometry (LLE-GC-MS) method. The results confirmed the presence of venlafaxine in most cases (19 cases), followed by sertraline (3 cases) and fluoxetine (3 cases) at concentrations below toxic levels.
authors.affiliation: Dpto. Anatomía Patológica y Ciencias Forenses, Facultad de Medicina, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Fernández
authors.affiliation: Dpto. Anatomía Patológica y Ciencias Forenses, Facultad de Medicina, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: V
authors.initials: V
authors.lastname: Taboada
authors.affiliation: Dpto. Anatomía Patológica y Ciencias Forenses, Facultad de Medicina, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Regenjo
authors.affiliation: Dpto. Anatomía Patológica y Ciencias Forenses, Facultad de Medicina, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Morales
authors.affiliation: Dpto. Anatomía Patológica y Ciencias Forenses, Facultad de Medicina, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Alvarez
authors.affiliation: Dpto. Química Analítica, Nutrición y Bromatología Facultad de Química, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain. Electronic address: tuchi.carro@usc.es.
authors.forename: A M
authors.initials: AM
authors.lastname: Carro
authors.affiliation: Dpto. Química Analítica, Nutrición y Bromatología Facultad de Química, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain. Electronic address: rosaantonia.lorenzo@usc.es.
authors.forename: R A
authors.initials: RA
authors.lastname: Lorenzo
mesh_terms: D000928:Antidepressive Agents / Q000097:blood* / Q000302:isolation & purification; D002853:Chromatography, Liquid; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D059627:Liquid Phase Microextraction; D015203:Reproducibility of Results; D014465:Ultrasonics
chemical_list: D000928:Antidepressive Agents
keywords: Dispersive-liquid-liquid microextraction; Experimental design; Human plasma; Second-generation antidepressants