Tunable Fluorine-Functionalized Scholl-Coupled Microporous Polymer for the Selective Adsorption and Ultrasensitive Analysis of Environmental Liquid-Crystal Monomers

Liquid-crystal monomers (LCMs), especially fluorinatedbiphenylsand analogues (FBAs), are identified to be an emerging generationof persistent organic pollutants. However, there is a dearth of informationabout their occurrence and distribution in environmental water andlacustrine soil samples. Herein, a series of fluorine-functionalizedScholl-coupled microporous polymers (FSMP-X, X =1-3) were designed and synthesized for the highly efficientand selective enrichment of FABs. Their hydrophobicity, porosity,chemical stability, and adsorption performance (capacity, rate, andselectivity) were regulated preciously. The best-performing material(FSMP-2) was employed as the on-line fluorous solid-phase extraction(on-line FSPE) adsorbent owing to its high adsorption capacity (313.68mg g(-1)), fast adsorption rate (1.05 g h(-1)), and specific selectivity for FBAs. Notably, an enrichment factorof up to 590.2 was obtained for FSMP-2, outperforming commercial C-18 (12.6-fold). Also, the underlying adsorption mechanism wasuncovered by density functional theory calculations and experiments.Based on this, a novel and automated on-line FSPE-high-performanceliquid chromatography method was developed for ultrasensitive (detectionlimits: 0.0004-0.0150 ng mL(-1)) and low matrixeffect (73.79-113.3%) determination of LCMs in lake water andlacustrine soils. This study offers new insight into the highly selectivequantification of LCMs and the first evidence for their occurrenceand distribution in these environmental samples.