Application Of Modified Magnetic Nanoparticles In The Extraction And Preconcentration Of Organic Pesticdes

The development of agricultural is rapid along with the massive product and wide use of pesticides. Human and animals’health will be affected by pesticides residues remained in environment, which attracted much attention. Since most of them are fat-soluble, it is difficult for organic pesticides to degradation and they will residue in the environment, such as water, air, soil and food. Sulfonylurea, organochlorine and organophosphorus pesticide residues are more widely and typical. Pesticides residues can affect plant, animal and human health through food accumulation. These characteristics make its harmful effects is quite significant. It is crucial to develop an efficient, sensitive, simple, environment-friendly detection method in the future.In this work, the synthesis of N-methylimidazolium ILs-modified magnetic material was conducted. This ILs upon immobilization on magnetic nanoparticle has been used as a sorbent for the dispersive solid phase extraction of organophosphorus pesticides residues in water. The prepared material was characterized. Parameters that can affect the extraction efficiency of the analytes were studied in detail. The results indicate that this method is an efficient extraction procedure for the analysis oforganophosphorus pesticides residues in water samples.A new PILs immobilized magnetic nanopartic le-based MSPE method combined with HPLC-ultraviolet detection has been developed for SUHs in soil samples. Compared with conventional synthesis, the microwave synthesis was time-saving, environmentally friendly, and simple. The PIL-modified MNPs had a large effective contact area, high viscosity and good interaction with the target compounds, which can provide rapid separation of SUHs from the sample solution with the aid of an external magnetic field, offers an environment-friendly and inexpensive method for sample extraction. A notable finding is that the adsorbent could be reused at least 19 times without an obvious decrease in the extraction efficiency. All of the experimental results clearly demonstrate that Fe3O4@SiO2@PILs (NTf2) is an attractive adsorbent for MSPE of herbicides in soil samples.The synthesis of magnetic nanopartic les with surface modification was conduct This magnetic nanopartic les with surface modification has been used as a sorbent for the dispersive solid phase extraction of pyrethroid residues in traditional chinese medicinal, organophosphorus pesticides in water and SUHs residues in soil. The prepared material was characterized. Parameters that can affect the extraction efficiency of the analytes were studied in detail. The results indicate that this method is an efficient extraction procedure for the analysis of pesticides residues in environment samples.PPY@SiO2@Fe3O4 was synthesized via one step polymerization in a water system without toxic organic solvent. Various characterization techniques confirmed the synthesis of the magnetic nanomaterial. It was then applied to extraction and analysis of four pyrethroids in traditional Chinese medicine (TCM) by GC-MS. Because of the unique advantages of combining PPY and magnetic nanoparticles, the modified magnetic nanoparticles have potential applications in dispersive solid-phase extraction (dSPE). The higher selectivity and recovery were obtained with small size PPY@SiO2@Fe3O4, when compare to the big size PPY@SiO2@Fe3O4. The results showed that PPY@SiO2@Fe3O4 is an effective absorbent that has a potential application in the extraction of pesticides in TCM.Compared with the conventional methods, the proposed methods in this article are more environmentally friendly, simpler, faster and more efficient. They give excellent performances in the extractions of environmental samples.