Magnetic covalent-organic frameworks for the simultaneous extraction of eleven emerging aromatic disinfection byproducts in water samples coupled with UHPLC–MS/MS determination

A simple method based on magnetic solid-phase extraction (MSPE) was developed for the simultaneous extraction of eleven emerging aromatic disinfection byproducts (DBPs) in water samples coupled with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) determination. A magnetic covalent-organic framework (COF) material, namely, Fe3O4 @TpBD, was facilely synthesized and fully characterized, followed by an MSPE process. Several important MSPE parameters, such as the magnetic ratio, Fe3O4 @TpBD amount and sample pH, were systematically investigated. Under optimal conditions, the limits of detection and quantification of this COF-MSPE-UHPLC-MS/MS method were as low as 0.07-1.81 ng/L and 0.24-5.99 ng/L, respectively. Good precision was obtained with relative standard deviations (RSDs) of 1.3-10.9% (intraday) and 4.3-15.9% (interday). Furthermore, the validated method was proven applicable to real water samples; for example, the recoveries were 86.8-115.1% for the secondary effluent, and several DBPs in swimming pool water were detected. Notably, the MSPE process required only 7 min, ensuring that the DBPs were relatively stable during the whole analysis process and that Fe3O4 @TpBD demonstrated excellent reusability. The COF-based MSPE method with simplicity, rapidity and efficiency provided an ideal sample pretreatment alternative to determine trace DBPs in complex matrices.