| A variety of polar organic pollutants are common pollutants in water and food,and becau se water is a strong polar solvent,these polar compounds have very strong hydrophilicity due to the principle of"similar solubility",so they are difficult to be adsorbed and detected in wat er and food.These polar compounds are highly toxic and can enter human body through food chain enrichment or skin contact,thus endangering human health.And because of their low c oncentration in food and water samples and the interference of matrix effect,they are very dif ficult to be detected.Therefore,the trace analysis and detection of polar organic compounds i n water has attracted extensive attention in the field of food safety.In this study,three novel functional covalent organic frameworks:TAPT-DHTA-COF,T APA-TFPB-COFs and TAPB-TFTA-COF were used as solid phase extraction fillers and disp ersive solid phase extraction adsorbents,respectively.New methods for the determination of p henoxycarboxylic acids,quinolones and perfluorinated compounds in food samples and drinki ng water samples were established.The applicability and accuracy of the method were verifie d,and the possible adsorption mechanism of different materials for the target was discussed.The main results are as follows:(1)TAPT-DHTA-COF prepared at room temperature was used as solid phase extractio-n adsorbent to enrich five phenoxycarboxylic acid herbicides in plant derived food,and then a nalyzed by LC-MS/MS.The specific porous structure,high specific surface area,high porosit y and stability of TAPT-DHTA-COF were characterized.Several experimental parameters wh ich significantly affect the extraction efficiency were studied and optimized.The experimental data showed that in the concentration range of 0.1-1000 ng·L-1,the LOD was 0.007-0.030 n g·g-1,the linear range was 0.10-40 ng·g-1,R?0.993,with good reproducibility and repeatabili ty.The intra day deviation was 0.31%-12%,n=5 and inter day deviation 3.4%-17%,n=5),and the reproducibility was good.This method has been successfully applied to the determination of phenoxycarboxylic acid herbicides in plant food.(2)The TAPA-TFPB-COFs was prepared at room temperature and used as solid phase extraction adsorbent to extract ultra trace polar quinolones from food and drinking water.TA PA-TFPB-COFs were characterized by scanning electron microscopy,fourier transform infrar ed spectroscopy and X-ray diffraction.The parameters affecting the extraction efficiency wer e optimized.Quinolones were quantified by liquid chromatography tandem mass spectrometr y.The advantages of the established method include low detection limit of 0.02-0.11 ng·L-1,wide linear range of 0.5-200 ng·L-1,R?0.997,good repeatability,intra day deviation?10.8%and inter day deviation?6.7%).The method has been successfully applied to the determi nation of quinolones in food and drinking water samples.(3)Covalent organic frameworks(TAPB-TFTA-COF)were prepared at room temperat ure and used as adsorbents for dispersive solid phase extraction of 12 perfluorinated compoun ds.The synthesized materials were characterized by scanning electron microscopy,transmissi on electron microscopy,fourier transform infrared spectroscopy.The parameters affecting the extraction efficiency were optimized.Perfluorinated compounds were quantified by liquid ch romatography tandem mass spectrometry.The advantages of the established method include l ow detection limit of 0.05-0.70 ng·L-1,wide linear range of 0.83-833 ng·L-1,R?0.984,good repeatability,intra day deviation?7.67%and inter day deviation?9.13%.The method has be en successfully applied to the determination of perfluorinated pollutants in drinking water samples. |
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