title: Determination of three antidepressants in urine using simultaneous derivatization and temperature-assisted dispersive liquid-liquid microextraction followed by gas chromatography-flame ionization detection.
abstract: This paper presents a fast and simple method for the extraction, preconcentration and determination of fluvoxamine, nortriptyline and maprotiline in urine using simultaneous derivatization and temperature-assisted dispersive liquid-liquid microextraction (TA-DLLME) followed by gas chromatography-flame ionization detection (GC-FID). An appropriate mixture of dimethylformamide (disperser solvent), 1,1,2,2-tetrachloroethane (extraction solvent) and acetic anhydride (derivatization agent) was rapidly injected into the heated sample. Then the solution was cooled to room temperature and cloudy solution formed was centrifuged. Finally a portion of the sedimented phase was injected into the GC-FID. The effect of several factors affecting the performance of the method, including the selection of suitable extraction and disperser solvents and their volumes, volume of derivatization agent, temperature, salt addition, pH and centrifugation time and speed were investigated and optimized. Figures of merit of the proposed method, such as linearity (r(2)  > 0.993), enrichment factors (820-1070), limits of detection (2-4 ng mL(-1)) and quantification (8-12 ng mL(-1)), and relative standard deviations (3-6%) for both intraday and interday precisions (concentration = 50 ng mL(-1)) were satisfactory for determination of the selected antidepressants. Finally the method was successfully applied to determine the target pharmaceuticals in urine.
authors.affiliation: Food and Drug Laboratories, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Ali Akbar Alizadeh
authors.initials: AA
authors.lastname: Nabil
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran.
authors.forename: Nina
authors.initials: N
authors.lastname: Nouri
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran.
authors.forename: Mir Ali
authors.initials: MA
authors.lastname: Farajzadeh
mesh_terms: D000328:Adult; D000928:Antidepressive Agents / Q000652:urine*; D005260:Female; D005410:Flame Ionization / Q000379:methods*; D006801:Humans; D057230:Limit of Detection; D016014:Linear Models; D059627:Liquid Phase Microextraction / Q000379:methods*; D008875:Middle Aged; D015203:Reproducibility of Results
chemical_list: D000928:Antidepressive Agents
keywords: antidepressants; derivatization; gas chromatography; temperature-assisted dispersive liquid-liquid microextraction; urine