Aminosilanized magnetic carbon microspheres for the magnetic solid-phase extraction of bisphenol A, bisphenol AF, and tetrabromobisphenol A from environmental water samples.

Aminosilanized magnetic carbon microspheres as a novel adsorbent were designed and fabricated. The adsorbent was used for the magnetic solid-phase extraction of bisphenols at trace levels from environmental water samples before liquid chromatography with tandem mass spectrometry analysis. The structure, surface, and magnetic behavior of the as-prepared aminosilanized magnetic carbon microspheres were characterized by elemental analysis, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, powder X-ray diffraction, and vibrating sample magnetometry. The effects of the experimental parameters were investigated by the Plackett-Burman design, and then the parameters that were significant to the extraction efficiencies were optimized through a response surface methodology. The aminosilanized magnetic carbon microspheres exhibited high adsorption efficiency and selectivity for bisphenols. Under optimal conditions, low limits of detection (0.011-2.22 ng/L), and a wide linear range (2-3 orders of magnitude), good repeatability (4.7-7.8%, n = 5), and reproducibility (6.0-8.3%, n = 3) were achieved. The results demonstrate that the novel adsorbent possesses great potentials in the determination of trace levels of bisphenols in environmental water samples.