Preparation of magnetic flower-like molybdenum disulfide hybrid materials for the extraction of organophosphorus pesticides from environmental water samples

Abstract

In this study, the magnetic flower-like molybdenum disulfide hybrid materials (Fe3O4/MoS2) were successfully synthesized by in-situ fabrication method and utilized in the magnetic solid-phase extraction of organophosphorus pesticides. Fe3O4 nanoparticles with different loading amounts of MoS2 were evaluated and detail characterized. The results showed that MoS2 played a key role with rapid and high adsorption capacity towards organophosphorus pesticides. The higher extraction efficiency and good magnetic performance were obtained with loading amount of 200 mg MoS2. Fe3O4 was attached on the surface of MoS2 with flower-like shape (500 nm in diameter). The parameters (amounts of adsorbents, adsorption time, solution pH, elution solvents and sample volumes) affecting magnetic solid-phase extraction efficiency were optimized. Under the optimum conditions, magnetic solid-phase extraction coupled with high liquid chromatography-tandem mass spectrometry for analyzing organophosphorus pesticides in environmental water samples was established. All the analytes exhibited good recoveries spiked at three different concentration levels (10, 20, 50 ng/mL) in water samples. The relative standard deviations were between 1.4% and 6.8%. The developed method showed high sensitivity and good potential use of this convenient and high efficient method for determining organophosphorus pesticides. More importantly, this study can provide a new magnetic adsorbent with extremely fast mass transfer rate for other potential trace contaminants.