Synthesis of DABCO-based ionic liquid functionalized magnetic nanoparticles as a novel sorbent for the determination of cephalosporins in milk samples by dispersive solid-phase extraction followed by ultra-performance liquid chromatography-tandem mass spectrometry†
In this study, DABCO-based ionic liquid-functionalized magnetic iron oxide nanoparticles (Fe3O4@[DABCO-DHP][Cl] NPs) were synthesized for the first time by the quaternization reaction with 1-(2,3-dihydroxypropyl)-1,4-diazabicyclo[2.2.2]octanylium chloride ([DABCO-DHP][Cl]) and chloro-functionalized magnetic Fe3O4 nanoparticles. The synthesized nanoparticles were exhaustively characterized by field emission-scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectrometry, X-ray diffraction, X-ray photoelectron spectroscopy, thermal gravimetric analysis, vibrating sample magnetometry, and zeta potential analysis. The Fe3O4@[DABCO-DHP][Cl] nanoparticles were utilized as a novel adsorbent for magnetic dispersive solid-phase extraction of a group of nine cephalosporins at ultra-trace levels from different milk matrices coupled with ultra-performance liquid chromatography-tandem mass spectrometry. The experimental parameters influencing the extraction efficiency were investigated by the univariate and multivariate optimization methods. Under the optimized conditions, the analysis method was established. The linear range of 0.1–400 μg kg−1 and the correlation coefficients of 0.9963–0.9998 were obtained. The limits of detection of the proposed method achieved were in the range of 0.02–1.18 μg kg−1 for all analytes and samples. Satisfactory recovery values ranged from 73.4% to 96.5% for all matrices with relative standard deviation values lower than 11.3%. The proposed method was efficient, sensitive, and practical for the determination of cephalosporins in milk samples.