Magnetic porous β-cyclodextrin polymer for magnetic solid-phase extraction of microcystins from environmental water...

Microcystins (MCs) are cyclic heptapeptide toxins and tumor promoters produced by cyanobacteria, which threaten the health of humans. In this study, magnetic porous β-cyclodextrin polymer (Fe₃O₄@SiO₂@P-CDP) was synthesized and characterized by transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray spectrometry, Fourier transform infrared spectrometry, X-ray diffraction, nitrogen adsorption porosimetry and vibrating sample magnetometer. The synthesized Fe₃O₄@SiO₂@P-CDP particles were then used for magnetic solid-phase extraction (MSPE) of MCs from environmental water samples, and exhibited excellent extraction performance, especially for MC-RR. Coupled with high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS), a simple, efficient and sensitive method for determination of trace levels of MCs was established. After the optimization of conditions, wide linear ranges (2.0-1000pgmL^-1), good linearity (r²≥0.9996) and acceptable repeatability (RSD≤9.4%, n=5) were obtained. The limits of detection (LODs, S/N=3) and limits of quantification (LOQs, S/N=10) for three MCs (MC-LR, MC-RR and MC-YR) were in the range of 1.0-2.0pgmL^-1 and 2.0-5.0pgmL^-1, respectively. Typical water samples were analyzed by the developed method, and trace levels of MC-LR and MC-RR were detected. The results demonstrate that the developed method has great potential for the determination of MCs in complicated matrix.