Fabrication of polymer‐modified magnetic nanoparticle based adsorbents for the capture and release of quinolones by manipulating the metal–coordination interaction

Functional polymers with a metal–coordination interaction have been fabricated for sample pretreatment. Poly(N‐4‐vinyl‐benzyl iminodiacetic acid‐co‐methacrylic acid‐co‐styrene)‐modified magnetic nanoparticles were prepared and used as solid‐phase extraction adsorbents for the analysis of quinolones by tuning the metal–coordination interaction. In the construction of the polymer‐based adsorbents, functional monomer (N‐(4‐vinyl)‐benzyl iminodiacetic acid) and comonomers (methacrylic acid and styrene) were fabricated onto the magnetic nanoparticles by free radical polymerization. Factors affecting the performance of the adsorbents were investigated, and the results revealed that Fe³⁺ played a vital role in the formation of metal–coordination adsorbents. Compared with other compounds, the resultant adsorbents displayed good selectivity to quinolones due to the metal–coordination complex (N‐4‐vinyl‐benzyl iminodiacetic acid‐Fe³⁺‐quinolones). Interestingly, the captured quinolones could be rapidly released by manipulating the metal–coordination interaction with Cu²⁺. The linearity range for analysis of the test quinolones was 0.025–2.0 μg/mL (R² > 0.999), and the recovery varied from 80.0 to 100.7%. Further, the proposed adsorbents were combined with high‐performance liquid chromatography for the analysis of quinolones in real urine samples. The results demonstrated that the prepared adsorbents have good selectivity and sensitivity for quinolones, showing great potential for drug analysis in real samples.