Preparation And Application Of Magnetic Particles Modified By Grafting Polymers With Naphthyl Side Chaines And Carbonizing Polyphenols-metal Coordination Polymers

The sample preparation is an essential procedure for the detection of trace substances in complex matrix.Magnetic solid phase extraction(MSPE)can simplify the adsorption procedure based on magnetic nanoparticles,and it is a fast and efficient extraction method.Using the multifunctional magnetic adsorbents can effectively enhance the extraction efficiency.Thus,the preparation of the multifunctional magnetic adsorbents is a frontier research in the area of separation and enrichment.The Fe3O4 nanoparticles are commonly used as the adsorbents of MSPE,but Fe3O4 suffers from aggregation and oxidation easily,and has few functional groups on the surface,thus it has poor selectivity for targets in complex matrices.Due to the specific multifunctional properties,high-density of adsorption sites of polymer and the high specific surface,good biocompatibility of carbon material,the polymers or carbon materials modified magnetic particles can enhance the stability of the nanoparticles and the functionality of magnetic adsorbent.In this paper,polymers and carbon materials modified magnetic particles were prepared and used for the separation and enrichment of non-steroidal anti-inflammatory drugs(NSAIDs)and phytohormones,respectively.The research includes:(1)The Si O2 coated Fe3O4 was used as the supporting material(Fe3O4@Si O2),the naphthalene acrylate(NA)was grafted from the surface of the Fe3O4@Si O2 via SI-ATRP to prepare the magnetic composites(Fe3O4@Si O2-PNA).The magnetic composites were used to enrich the NSAIDs through strong ?-? interaction and hydrophobic interaction due to the large ?-electron system and two conjugated aromatic rings of PNA.The adsorption recoveries of In Do and DIC were increased three times after the modification of PNA.The Fe3O4@Si O2-PNA was used for the detection of In Do and DIC in environmental water samples under the optimized extraction conditions.The limits of the detection were between 0.61-0.64 ng/m L,the recoveries were in the range of 62.1%-96.7%,the intra-and inter-day relative standard deviations(RSDs)were lower than 11.9%.The result indicated that the proposed method have low detection limits and is a simple and rapid method.(2)The tannic acid(TA-Fe3+)coordination polymers were modified on the surface of the PDA coated Fe3O4 via hydrothermal method,and then it was used as the precursorfor the preparation of the magnetic carbon materials Fe3O4@C-HT.The chemical composition,morphology and specific surface area of the magnetic carbon materials were characterized.The TA-Fe3+ polymers can stability modified on the surface of the magnetic particles due to the PDA coater and can convert to the uniform carbon layer after carbonization.The prepared carbon materials have high specific surface area.The magnetic carbon materials were used for the enrichment of phytohormones.The results shown that Fe3O4@C-HT can effectively enrichment the phytohormones from the solution and have rapid transfer rate,the adsorption and desorption can be completed in 1 min.This material can be expected to detect the trace phytohormones.