Preparation of highly hydrophilic magnetic nanoparticles with anion-exchange ability and their application for the extraction of non-steroidal anti-inflammatory drugs in environmental samples.

Diallyldimethylammonium chloride modified magnetic nanoparticles were synthesized by the "thiol-ene" click chemistry reaction. Diallyldimethylammonium chloride rendered the material plenty of quaternary ammonium groups, and thus the excellent aqueous dispersibility and anion-exchange capability. The novel material was then used as the magnetic solid-phase extraction sorbent to extract eight non-steroidal anti-inflammatory drugs from water samples. Combined with high-performance liquid chromatography and ultraviolet detection, under the optimal conditions, the developed method exhibited wide linearity ranges (1-1000, 2-1000, and 5-1000 ng/mL) with recoveries of 88.0-108.6% and low limits of detection (0.3-1.5 ng/mL). Acceptable precision was obtained with satisfactory intra- and inter-day relative standard deviations of 0.4-4.4% (n = 3) and 1.1-5.5% (n = 3), respectively. Batch-to-batch reproducibility was acceptable with relative standard deviations <9.7%. The hydrophilic magnetic nanoparticle featured with quaternary ammonium groups showed high analytical potential for acidic analytes in environmental water samples.