GC-MS analysis of fluoxetine and its active metabolite norfluoxetine in human urine

Abstract

A gas chromatographic-mass spectrometric (GC-MS) method was developed for detection of fluoxetine and its active metabolite norfluoxetine in urine. Liquid and solid phase extraction were applied to urine samples using maprotiline as an internal standard (IS). The GC-MS analysis were carried out using HP-5MS capillary column. The linearity ranges of the method were 5-75 ng mL -1 for fluoxetine and 6-125 ng mL -1 for norfluoxetine by solid phase extraction (SPE), and 10-80 ng mL -1 for fluoxetine and also norfluoxetine by liquid-liquid extraction (LLE). Also the range of detection limits were between 1-10 ng mL -1 , the range of quantification limits were between 5-10 ng mL -1 for fluoxetine and norfluoxetine by both SPE and LLE. The range of recoveries were between 87 -109 % by both SPE and LLE for analytes. The developed method allowed clinical and toxicological analysis of fluoxetine and norfluoxetine in urine samples.KEY WORDS: Fluoxetine; Norfluoxetine; Gas Chromatography-Mass Spectrometry; LiquidLiquid Extraction; Solid-Phase Extraction.Münevver Aç kkol 1 , Dilek Salk m 1 GC-MS analysis of fluoxetine and its active metabolite norfluoxetine in human urine DOI: 10.12991/201014456 99 Açıkkol ve Salkım et al. Marmara Pharm J 14: 98-103, 2010. plicity, sensitivity, reproducide nature and low cost. There were only a few published methods about the simultaneous GC-MS analysis of fluoxetine and norfluoxetine in urine.Therefore, the presented study was designed for a GC-MS method for the simultaneous determination of fluoxetine and norfluoxetine in urine using maprotiline as an internal standard (IS) with a simple LLE and SPE procedure. MATERIALS AND METHODS Chemicals and reagentsFluoxetine hydrochloride was purchased from Sigma Aldrich (Steinheim, Germany) and kindly supplied by Abdi Ibrahim Pharma A.G (Istanbul, Turkey). Norfluoxetine hydrochloride was purchased from Sigma Aldrich (Steinheim, Germany). Maprotiline hydrochloride (IS) was kindly supplied by Novartis Pharma A.G (Istanbul, Turkey).Ammonia solution (25%), hexane, dichloromethane, ethyl acetate, acetic anhydride, pyridine, methanol and isopropanol were purchased from Merck (Darmstadt, Germany). Purity of all solvents are HPLC grade. Urine samplesUrine samples were collected from healthy volunteers whereas clinical samples from patients (14 females and 6 males; Aged 18-64) submitted fluoxetine treatment at Istanbul University Medicine Faculty of Cerrahpasa Department of Psychiatry. Samples were collected approximately 12 hours after the administration of the daily dose of 20 mg of fluoxetine from patients treated constantly for at least 2 weeks. The urine samples stored in appropriate polytetrafluoro ethylene (PTPE) flasks at -20ºC until analyzed and were found to be stable for at least 1 month. The patients gave their informed consent for these analyses. The study protocol was approved by the Ethics Committee of The Faculty of Cerrahpasa Medicine in Istanbul University. Preparation stock and calibration standardsStock solutions of fluoxet...

Thin‐film solid‐phase microextraction of fluoxetine using a novel sorbent prepared by direct decoration of zeolitic imidazolate frameworks on the surface of polyacrylonitrile electrospun nanofibers

“…Thus, developing a sensitive method for measuring fluoxetine in aqueous and urine samples is important. So far, extraction and microextraction techniques such as liquid-liquid extraction (LLE) [3], SPE [4], magnetic-solid-phase extraction (m-SPE) [5], solid-phase microextraction (SPME) [6], stir bar sorptive extraction [7], and liquid-phase microextraction (LPME) [8] followed by chromatography [9], spectrofluorometric [5], and spectrophotometric [10] determination have been applied for analyzing fluoxetine in aqueous and biological samples. Thin-film solid-phase microextraction (TF-SPME) is another geometry of SPME that uses a sorptive thin film with a large surface-area-to-volume ratio in order to enhance the amounts of the analyte extracted and provides higher sensitivity and faster extraction time [11,12].…”