Synthesis Of Magnetic Enrichment Materials And Applications In The Extraction And Separation Of Trace Components

With the continuous development of society,people in the food and drug safety and other aspects of the environment,more and more attention,food,detection and analysis of harmful substances in the environment and drugs have also been widespread concern in all sectors of society.Therefore,the establishment of a more efficient,simple operation,friendly environment and good selectivity of the sample pretreatment technology is imperative,this it will become the leading direction of chemistry analysis.In this thesis,three kinds of biogenic amines and nine kinds of bisphenol compounds were detected by using high performance liquid chromatography（HPLC）with magnetic multi walled carbon nanotubes（CNTs）and magnetic ionic liquids as extractant respectively.The main research work of this paper is as follows:1.In this paper,magnetic carbon nanotubes（MWCNT）were synthesized and characterized by scanning electron microscopy（SEM）,Fourier transform infrared spectroscopy（FT-IR）and vibrating sample magnetometer（VSM）.MWCNT was used as magnetic extractant and HPLC analysis method was used to detect biogenic amines,histamine（His）,and Ben（Try）in liquid beverage.The results showed that the synthesized MWCNT exhibited higher adsorption capacity and better extraction capacity for three biogenic amines,and the extraction rate was above 95%.Under the optimal conditions,the linear range is 100-2000 ng/m L,the detection limit of 2.96-5.26 ng/mL,this method is applied to beer,liquor,determination of biogenic amines in fruit juice samples,and the standard recovery was 87.6%-102.1%,the relative standard deviation is 2.9%-7.3%,proved that this method has good ability in practical application.2.Magnetic ionic liquids([P_6,6,6,14][FeCl₄]/MIL)were successfully synthesized,The study of extraction kinetics and thermodynamics showed that the extractant had higher extraction efficiency and adsorption capacity for 9 kinds of bisphenol compounds（BPs）.A new method for simultaneous detection of nine kinds of BPs in tap water and environmental water was established by using [P_6,6,6,14][FeCl₄]/MIL as a liquid phase extraction agent combined with HPLC method.The enrichment conditions and chromatographic parameters were optimized,and the feasibility of the method was verified by the standard recovery method.Under the optimal conditions,the standard recovery of the method was between 76.9 and 104.2%,the relative standard deviation was less than 1.32%,and the quantitative limit was between 1.12-4.35 ng m L-1.The results were satisfactory.3.Magnetic ionic liquids([P_6,6,6,14][FeCl₄]/MIL)were successfully synthesized,magnetic ionic liquid as magnetic extractant,scanning electron microscopy（SEM）,Fourier transform infrared spectroscopy（FT-IR）and vibrating sample magnetometer（VSM）were used to characterize the materials.Combined with HPLC analysis,the biogenic amines（His）,amine（Try）and Ben were detected simultaneously.By optimizing a series of extraction conditions,it is shown that the synthesized magnetic ionic liquid has higher extraction capacity and better extraction capacity for three biogenic amines,and the adsorption rate can reach more than 95%.Under the optimal conditions,the linear range is 100-2000 ng/m L,the detection limit of 3.46-4.96 ng/m L,this method is applied to beer,liquor,determination of three kinds of environmental pollutants in fruit juice samples,and the standard recovery was 84.7%-108.5%,the relative standard deviation is 2.9%-7.3%,proved that this method has good effect on in the practical application.