Magnetic solid phase extraction of bisphenol A, phenol and hydroquinone from water samples by magnetic and thermo...

Present study prepared a new magnetic and thermo dual-responsive core-shell nanomaterial (Fe@SiO₂@poly(N-isopropylacrymide-co-methacrylic acid, Fe@SiO₂@PNIPAM-co-MAA), which was characterized by transmission electron microscopy and X-ray diffraction techniques. The new nanomaterials integrated with the magnetism of nanoscale zero valent iron material and thermo-response of the copolymers, and were utilized to investigate the adsorption capacity for typical phenols such as bisphenol A, phenol and hydroquinone from water samples, and the results showed that the magnetic and thermo dual-responsive core-shell nanomaterial exhibited good adsorption ability to typical phenols. Based on these, a sensitive method was developed for the determination of bisphenol A, phenol and hydroquinone using as-prepared magnetic nanoparticles as the magnetic solid phase extraction sorbent prior to high performance liquid chromatography coupled with variable wavelength detection. Under the optimal conditions, linear linearity was obtained over the range of 0.1-500 μg L^-1 with the correlation coefficients (r²) above 0.996. The detection limits of three analytes were in the range of 0.019-0.031 μg L^-1, and the precisions were all less than 4.8% (n = 6). The developed method was evaluated with real water samples and excellent spiked recoveries in the range of 94.0-105.4% were achieved. These results indicated that the proposed method was a robust analytical tool and a useful alternative for routine analysis of such pollutants.