Fabrication of Novel Magnetic Crown Ether-based Microporous Organic Network for Efficient Magnetic Solid-Phase...

Chlorophenols, polar priority pollutants with carcinogenic, teratogenic, and mutagenic effects, are ubiquitous in environmental waters and pose risks to aquatic organisms and human health. However, their presence at trace levels and high polarity hinders their selective enrichment and accurate quantification. To address this, we ingeniously devised and constructed a novel crown ether functionalized magnetic microporous organic network (Fe₃O₄@CE-MON) as an efficient adsorbent for magnetic solid-phase extraction (MSPE) of trace chlorophenols from complex aqueous matrices. Synthesized by coupling brominated 18-crown-6 ether with aromatic alkynyl groups, Fe₃O₄@CE-MON integrates the conjugated MON framework, molecular recognition capability of crown ether cavities, and magnetic responsiveness of Fe₃O₄ nanoparticles, achieving selective chlorophenols enrichment via hydrophobic, π-π stacking, and hydrogen bonding interactions. After systematically optimizing key MSPE parameters, a sensitive MSPE-high-performance liquid chromatography-ultraviolet method was established, featuring low detection limits (0.3-0.5 µg L^-1), a wide linear range (1.0-500 µg L^-1), excellent reproducibility, and superior enrichment efficiency. This is the first example of fabricating crown ether-based MMON for MSPE, providing a rapid and sensitive method for monitoring trace chlorophenols in complex environmental waters. It also expands MON monomer diversity and highlights the potential of combining supramolecule crown ether with porous MONs in sample pretreatment.