Solid-Phase Microextraction Coupled to Gas Chromatography-Mass Spectrometry for the Analysis of Famoxadone in Wines, Fruits, and Vegetables

A sensitive, selective, and solvent-free method based on direct immersion solid-phase microextraction (DI-SPME) followed by gas chromatography with mass spectrometry (GC-MS) is proposed for the determination of trace amounts of famoxadone in wines, fruits, and vegetables. Parameters affecting the sample enrichment step, such as sample mass, ionic strength, adsorption and desorption times, and temperatures were carefully optimized. A polar 85 mu m polyacrylate fiber was found to be suitable for extraction at 60 degrees C in 20min under continuous stirring. Desorption was carried out at 270 degrees C for 5min. Undiluted wine samples and diluted extracts obtained from the solid samples submitted to an ultrasound treatment in the presence of ethanol were quantified against external aqueous standards prepared in 12% ethanol (v/v). Under the optimized conditions, detection limits of 5ng L-1 and 10pgg-1 were obtained for liquid and solid samples, respectively. SPME-GC-MS analysis yielded good repeatability (RSD under 10% in all cases). The method provided recoveries of 91.6-110.9% from spiked samples. The method was applied to different samples, and none of them was found to contain famoxadone at concentrations above the corresponding detection limits.