Porous eco–friendly fibers for on–line micro solid–phase extraction of nonsteroidal anti–inflammatory drugs from urine and plasma samples

Abstract

In this study, cellulose acetate (CA) fibers were prepared using different solvent systems in electrospinning. The recorded scanning electron microscopy micrographs indicated that the morphology of the prepared fibers is closely associated with the type of electrospinning solvents. The prepared CA fibers were used as an extractive phase for on–line micro–solid phase extraction (μ-SPE) of nonsteroidal–inflammatory drugs (NSAIDs) in biological samples pursued by HPLC–UV determination. Work conducted on this research ascertained that the use of dichloromethane:acetone (3:1, v/v) solvent system in the CA dissolution for electrospinning, leads to the formation of porous ribbon–like fibers and subsequent excellent extraction efficiencies for the selected drugs. Moreover, the effects of diverse parameters on the extraction efficiency were surveyed and optimized. The proposed method was used for determination of naproxen, diclofenac and mefenamic acid in human urine and plasma samples. The optimized method was validated and the limits of detection (1.0–2.4 μg L−1), limits of quantification (3.3–8.0 μg L−1) and linear dynamic range (4.0–1000.0 μg L−1) were obtained. The reproducibility (relative standard deviation: 2.6–7.9%) was in an acceptable range. Trueness of the procedure was accomplished through recovery assays in urine (94–105%) and plasma (85–102%) samples, indicating the minor contribution from the sample matrix. Finally, the CA porous fibers within the framework of the μ-SPE method were found to be appropriate for the separation and determination of the selected drugs in urine and plasma samples collected from treated patients. Also, the adsorption behavior of the porous fibers was well described by Freundlich isotherm and porous fibers showed acceptable adsorption capacity.