An electrospun magnetic nanocomposite for a facile micro-scaled analysis approach

A magnetic polyurethane (PU) nanocomposite was synthesized by an electrospinning technique and applied for isolation and preconcentration of fluoxetine from aquatic and biological samples. The nanocomposite was electrospun using a PU polymer solution containing the dispersed magnetic nanoparticles. The magnetic properties of iron nanoparticles, along with the use of an electrospinning technique, led to the formation of a suitable sorbent toward isolation of fluoxetine. The magnetic PU nanofibers could be subsequently removed from the sample solution by applying a permanent magnet. The scanning electron microscopy (SEM) image of the magnetic PU nanofibers confirms that their diameters are in the range of 68–113 nm. The major parameters influencing the morphology of the magnetic PU nanofibers, comprising the weight ratio of iron and PU components, the applied voltage and the coating time, were optimized. Moreover, parameters including the eluting solvent, amount of sorbent, extraction time, pH and salinity of aqueous samples were considered for optimization. The detection limit of the developed method under optimized conditions and using fluorescence spectrometry was 1 μg L−1. The relative standard deviation (n = 5) at a concentration level of 150 μg L−1 was 2%. The method was linear in the range of 50–5000 μg L−1 with a correlation coefficient of 0.9997. The whole procedure proved to be conveniently rapid, efficient and economical to extract fluoxetine from environmental and biological samples. Eventually, the developed method was applied to the analysis of water, urine, milk and plasma samples and relative recoveries of 76 to 99% were achieved.