Analysis Of Environmental Pollutants By Solid Phase Microextraction Based On Metal Organic Frameworks

Metal organic frameworks(MOFs)are a kind of self-assemled coordination polymers with infinite structures which are constructed from clusters or chains of metal ions connected by organic linkers.MOFs have been widely applied in sample preparation due to its unique properties.In this paper,three kinds of MOFs were prepared based on carboxyl ligand and different metal ions,which were used as the coatings of solid phase microextraction(SPME).The coatings combined with GC-MS method was successfully used in the effective enrichment and sensitive analysis of polycyclic aromatic hydrocarbons(PAHs),polychlorinated biphenyls(PCBs)and pesticides.The paper includes the following four parts.1.Overview of sample preparation,the theory of SPME and the classifications of fiber coating was summarized.The characteristics,preparation,application of MOFs were introduced.Finally,the research content and research significance of the paper were introduced.2.MOF-235(Fe)coating fibers were prepared by in situ polymerization.The coating fibers had the stable structure,the same size and high surface(1914.37 m2/g).Based on the homemade MOFs-coating fibers and GC-MS,a method for simultaneous extraction and determination of fourteen pesticides was developed.All the analytical results demonstrated that the method was with good linearity range.The linear range of the method ranged from 0.01 ng/mL to 10.0 ng/mL,and the correlation coefficient of the method was from 0.9925 to 0.9999.The limits of detection of the fourteen pesticides were between 0.001 and 0.08 ng/mL.Finally,the method was applied to extract the pesticides from cucumber juice with good recoveries from 79.3%to 116.8.6%and satisfactory reproducibility.3.A high-temperature resistant HKUST-1-coating fibers were prepared.A method of simultaneous extraction and determination of sixteen PAHs was developed with above coating fibers.The factors influencing extraction and desorption were optimized in detail.The linear range of the method ranged from 0,01 ng/mL to 10.0 ng/mL,the correlation coefficient and detection limit of the method were 0.9949-0.9995 and 0.003-0.05 ng/mL,respectively.The recoveries of the method in Xihe water were between 81.4%-115.1%d the RSD were between 2.3%-11.3%(n=3).4.Cu(NO3)2·3H2I,H3BTC and C3N3(NH2)3 were used to prepare HKUST-1/g-C3N4-coating fibers.A method for simultaneous extraction and determination of seven PCBs was established.Under the optimal conditions,the linear range of the method ranged from 0.005 ng/mL to 10.0 ng/mL,the correlation coefficient were from 0.9923 to 0.9991,the limits of detection were between 0.001-0.07 ng/mL.The recoveries of the method in seawater were between 78.3%-113.6%,with the RSD less than 11.5%(n=3).