Magnetic solid phase extraction based on NiFe2O4 pyridyl-based microporous organic network for detection of 10 triazine herbicides in environment water by gas chromatography–mass spectrometry

It is crucial to select highly efficient adsorbents to separate and enrich trace analytes during sample pretreatment process. In this study, NiFe 2 O 4 pyridyl-based microporous organic network (NiFe 2 O 4 /PMON) was prepared using a fast and simple ultrasonic assisted method, which could be completed within 2 h. A magnetic solid phase extraction method based on 3 mg NiFe 2 O 4 /PMON as an extraction adsorbent was developed. Combining with GC–MS, an effective method for simultaneous detection of 10 triazine herbicides was established. The proposed method showed high sensitivity (LODs range of 0.19–0.46 ng/L), good precision (RSD below 8.3 %), and strong reliability, with spiked recovery rates between 70.5 and 108.4 %. NiFe 2 O 4 /PMON exhibited strong affinity for triazine herbicides through π–π, hydrophobic and hydrogen bond interactions. This study provides new ideas for the composite method of magnetic nanoparticles with MON. In addition, by extending the combination of MON and magnetic oxides, it can be used for the efficient detection of pesticide residues in water.