Polythiophene-coated Fe3O4 superparamagnetic nanocomposite: Synthesis and application as a new sorbent for solid-phase extraction

In the present work, a novel type of superparamagnetic nanosorbent, polythiophene-coated Fe3O4 nanoparticles (Fe3O4@PTh NPs), have been successfully synthesized. The synthesized NPs were characterized by scanning electron microscopy (SEM), Fourier transform-infrared (FT-IR) spectroscopy, and thermal gravimetric analysis (TGA). The synthesized Fe3O4@PTh NPs were applied as an efficient sorbent for extraction and preconcentration of several typical plasticizer compounds (di-n-butyl phthalate (DBP), di-(2-ethylhexyl) phthalate (DEHP), and dioctyl adipate (DOA)) from environmental water samples. Separation of Fe3O4@PTh NPs from the aqueous solution was simply achieved by applying external magnetic field. Separation and determination of the extracted plasticizers was performed by gas chromatography–flame ionization detection (GC–FID). Several variables affecting the extraction efficiency of the analytes i.e., amount of NPs sorbent, salt concentration, extraction time, and desorption conditions were investigated and optimized. The best working conditions were as follows: amount of sorbent, 100 mg; NaCl concentration, 30% (w/v); sample volume, 45 mL; extraction time, 10 min; and 100 μL of ethyl acetate for desorption of the analytes within 2 min. Under optimized conditions, preconcentration factors for DBP, DEHP, and DOA were obtained as 86, 194, and 213, respectively. The calibration curves were linear (R2 > 0.998) in the concentration range of 0.4–100 μg L−1 for both DEHP and DOA and 0.7–100 μg L−1 for DBP. The limits of detection (LODs) were obtained in the range of 0.2–0.4 μg L−1. The intra-day relative standard deviations (RSDs%) based on four replicates were obtained in the range of 4.0–12.3%. The proposed procedure was applied to analysis of water samples including river water, bottled mineral water, and boiling water exposed to polyethylene container (after cooling) and recoveries between 85 and 99% and RSDs lower than 12.8% were obtained.

In the present work, polythiophene-coated Fe3O4 nanoparticles (Fe3O4@PTh NPs) have been successfully synthesized. The synthesized Fe3O4@PTh NPs were applied as an efficient sorbent for extraction and pre-concentration of several typical plasticizer compounds from environmental water samples.Figure optionsDownload as PowerPoint slideHighlights
► A novel polythiophene-coated Fe3O4 nanoparticles (Fe3O4@PTh NPs) was synthesized.
► The synthesized Fe3O4@PTh NPs were characterized by using different instruments.
► The Fe3O4@PTh NPs were applied as a sorbent for extraction of several plasticizers.
► After extraction, separation of NPs from solution was achieved by a magnetic field.
► The proposed procedure was applied to analysis of the analytes in real water samples.