Magnetic nanoparticles modified with polyfuran for the extraction of polycyclic aromatic hydrocarbons prior to their determination by gas chromatography

We describe magnetite nanoparticles modified with polyfuran (PFu/Fe₃O₄) and their use as adsorbents for the solid-phase extraction of the polycyclic aromatic hydrocarbons (PAHs) naphthalene, fluorene and anthracene from water and urine samples. The PFu/Fe₃O₄ nanocomposite was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy and vibrating sample magnetometry (VSM). The adsorbent was magnetically separated from the sample, extracted with dichloromethane, and the extracts were submitted to gas chromatographic analysis with flame ionization detection. The amount of adsorbent, adsorption and desorption time, salt addition and desorption solvent were optimized. The method displays detection limits (at an S/N ratio of 3) in the range from 5 to 20 pg mL⁻¹, and the limits of quantification (at an S/N ratio of 10) are between 20 and 50 pg mL⁻¹. Relative standard deviations (RSDs) for intra- and inter-day precision are 4.1–5.6, and 5.3–6.5 %, respectively. The feasibility of the method was demonstrated by extracting and determining PAHs in (spiked) real water and urine samples. (author)