Covalent Organic Frameworks-Based Solid-Phase Microextraction Probe for Rapid and Ultrasensitive Analysis of Trace Per- and Polyfluoroalkyl Substances Using Mass Spectrometry.

Rapid and ultrasensitive analysis of trace pollutants in complex matrices is of significance for understanding their environmental behaviors and toxic effects. Here a novel method based on the integration of solid-phase microextraction (SPME) and nanoelectrospray ionization mass spectrometry (nanoESI-MS) was developed for rapid and ultrasensitive analysis of trace per- and polyfluoroalkyl substances (PFASs) in environmental and biological samples. A novel SPME probe with F-functionalized covalent organic frameworks (COFs) coating was designed for highly selective enrichment of trace PFASs from complex samples. After extraction, the loaded COFs-SPME probe was directly appplied to nanoESI-MS analysis under ambient and open-air conditions. The method showed satisfactory linearities between 1 and 5000 ng/L for 14 investigated PFASs in water, with correlation coefficient values no less than 0.9952. The limits of detection and quantification varied from 0.02 to 0.8 ng/L and 0.06 to 3 ng/L, respectively. By using the proposed method, ultrasensitive detection of PFASs in environmental water and whole blood was successfully achieved.