Analysis of\nTrace Enrofloxacin in Environmental Waters\nby a Surface Molecular Imprinting Technique

Surface-imprinted polymers (ZIF-67@MIPs) supported by\nZIF-67 were\nprepared by precipitation polymerization using enrofloxacin (ENR)\nas the template molecule, methacrylic acid as the functional monomer,\nand ethylene glycol dimethacrylate as the cross-linker. ZIF-67@MIPs\nwere characterized by Fourier transform infrared spectrometry, X-ray\ndiffraction, scanning electron microscopy, and particle size distribution.\nThe adsorption performance of the polymer was studied. The adsorption\nequilibrium was reached within 30 min. The maximum adsorption was\n9.02 μg·mg<sup>–1</sup>. The imprinting factor was\n2.58. The polymer was then used as a sorbent of a solid-phase extraction\ncolumn for the separation and purification of ENR in real water samples.\nThe extraction conditions were optimized. The method was established\nby high-performance liquid chromatography, and the linearity was verified\nby UPLC-MSMS. The correlation coefficient and limits of detection\nand quantification were 0.9999, 0.23 ng·mL<sup>–1</sup>, and 0.76 ng·mL<sup>–1</sup>, respectively. The recoveries\nwere in the range of 83.79–100.68%; the relative standard deviation\nwas 4.46–7.35%. The above data indicated that the method could\nbe used for the separation and enrichment of ENR in real samples.