Tailored novel multifunctional benzyl-functionalized magnetic ionic liquid for rapid and efficient monitoring of trace fluoroquinolones in food samples.

• Three Benzyl-functionalized MIL with novel structure were successfully fabricated. • MIL has the multi-function of extraction, visual observation and magnetic separation. • The functionalized MIL showed excellent extraction ability for FQs in milk and honey. • MIL-DLLME is a simple, rapid, efficient and sensitive method for trace FQs monitor. • The LOD, recovery and RSD were 0.47–0.56 μg/L, 90.8 %–107.8 %, and 5.4 % respectively. The novel hydrophobic cobalt anion-based benzyl-functionalized magnetic ionic liquid (MIL) was first designed, synthesized, and employed as a multifunctional extractant (for extraction, visual observation, and magnetic separation) for fast dispersive liquid–liquid microextraction of fluoroquinolones (FQs). According to the aromatic structure of FQs, three benzyl-functionalized MILs were customized by introducing various aromatic functional groups (benzyl, paracetyl phenyl, and m -methoxyphenyl) to justify the extraction efficiency and selectivity. In particular, the paracetyl phenyl functionalized MIL showed superior extraction efficiency among others due to its hydrophobicity and strong interactions of hydrogen bonding and π-π stacking. Moreover, under optimal conditions, the limits of detection were as low as 0.47–0.56 μg/L, and the enhancement factors were as high as 88–95. The recoveries were between 90.8 % and 107.8 %, and the relative standard deviation was less than 5.4 %. Ascribed to these outstanding experimental results, the benzyl-functionalized MIL is a potential magnetic extractant for detecting trace FQs in food samples. [ABSTRACT FROM AUTHOR]