A comparative study on different functionalized mesoporous silica nanomagnetic sorbents for efficient extraction of parabens

Different silica-based magnetic sorbents including mesoporous silica–Fe3O4 nanocomposite (Fe3O4@MCM-41), amino-functionalized mesoporous silica–Fe3O4 nanocomposite (Fe3O4@MCM-41–NH2) and graphene oxide/amino-functionalized mesoporous silica–Fe3O4 nanocomposite (Fe3O4@MCM-41–NH2–GO) were synthesized and their extraction efficiencies were compared in solid-phase extraction procedure of important parabens prior to gas chromatography–flame ionization detection. The sorbents extraction efficiencies followed the order of Fe3O4@MCM-41–NH2 > Fe3O4@MCM-41–NH2-GO > Fe3O4@MCM-41. Parameters affecting SPE procedure including amount of sorbent, eluting solvent type, adsorption and desorption times, and ionic strength were studied and optimized. The method’s performance was studied in terms of accuracy, linearity, precision and limits of detection. Detection limits of the method were <0.9 µg L−1 and linearity was in the range of 10–1000 µg L−1. Finally, the applicability of the proposed method was demonstrated for extraction of selected parabens in some cosmetic products. Good quantitative recoveries for spiked samples (85–107 %) and satisfactory precision (RSD ≤ 5.6 %) were also obtained.