Magnetic surface molecularly imprinted polymer for selective enrichment and detection of nitrofuran metabolite...

Nitrofuran metabolites are of regulatory concern due to their persistence and health risks, yet their simultaneous detection in water remains challenging. In this study, a magnetic surface molecularly imprinted polymer (MIP) was developed for the selective enrichment of four nitrofuran metabolites. A dual-template strategy using 1-aminohydantoin (AHD) and 3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ) was employed, with methacrylic acid as the functional monomer and a choline chloride-p-coumaric acid deep eutectic solvent as an auxiliary monomer. Chitosan-modified magnetic halloysite nanotubes (CS-Fe₃O₄@HNT) served as carriers, and surface imprinting polymerization was applied. The material was characterized by scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, and thermogravimetric analysis, confirming successful imprinting. The adsorption conditions were optimized using single-factor and orthogonal experiments. Coupled with high-performance liquid chromatography with ultraviolet detection, a highly linear analytical method was established. Spiked recoveries from water samples (lake, aquaculture tank, and tap water) ranged from 70.83 % to 96.39 %, with relative standard deviations (RSDs) of 0.11-9.8 %. The limits of detection (LODs) and quantification (LOQs) were 0.25-0.93 ng/mL and 0.84-3.11 ng/mL, respectively. Zebrafish embryo assays confirmed that the imprinted material was non-toxic (p > 0.05), whereas nitrofuran metabolites caused developmental malformations, edema, and mortality. In co-exposure experiments, the material significantly reduced both mortality and malformation rates (p < 0.05), demonstrating excellent environmental compatibility. This work represents the first report of a molecularly imprinted material capable of simultaneously recognizing four nitrofuran metabolites. The developed approach offers a sensitive and reliable platform for monitoring nitrofuran residues in water with potential for environmentally safe remediation.