Zeolitic imidazolate framework functionalized magnetic multiwalled carbon nanotubes as efficient adsorbents for rapid...

Herein, a new, environmentally friendly, and economical magnetic solid-phase extraction method for fluoroquinolones (FQs) from milk samples was developed using novel recyclable zeolitic imidazolate framework functionalized magnetic multiwalled carbon nanotubes (Fe₃O₄@MWCNTs@SiO₂@ZIF-8) as adsorbents. Various characterization techniques, including scanning electron microscopy, N₂ adsorption-desorption analysis, and vibrating sample magnetometry, demonstrated that the adsorbent possessed a remarkable specific surface area, pore volume, and superparamagnetic properties, rendering it an excellent adsorbent. Combined with high-performance liquid chromatography, this method exhibited excellent linearity (R² ≥ 0.9991) over the concentration range of 0.5-500 μg L^-1, low limits of detection (0.10-0.34 μg kg^-1), and low limits of quantification (0.30-1.00 μg kg^-1). Finally, the developed method was successfully applied to analyze FQs in milk samples with recoveries ranging from 83.3% to 107.7% and relative standard deviations below 4.2%. The high efficiency and sensitivity of this method highlight the potential application of Fe₃O₄@MWCNTs@SiO₂@ZIF-8 for analyzing FQs in complex matrices.