| Environmental pollutants are one of the most serious problems affecting human health.The rapid development of urbanization and industrialization has resulted in the constant increase of environmental pollutants,which gradually accumulate in human body.However,even very low levels of pollutants can have significant and persistent effects on human health.Therefore,the effective detection of environmental pollutants is very important for human health.The content of these pollutants is very low in the external environment,and the actual environment matrix is complex,so the influence of matrix can be removed and the detection sensitivity can be improved by enrichment technology.In this thesis,off-line and on-line dual concentration capillary electrophoresis was used to detect the concentration of two kinds of drugs in environmental water samples.The main research contents are as follows:1.The magnetic carbon nanotubes coated with polydopamine（PDA-coated M-MWCNTs）composite has been prepared.Then,solid phase extraction was carried out with mixed semi-micelles coated with PDA-coated M-MWCNTs.Combined with the sweep on column method of capillary electrophoresis,a mixed semi-micellar magnetic solid phase extraction-sweep on column dual enrichment capillary electrophoresis analysis platform was established.The magnetic composites were characterized by transmission electron microscope,infrared spectrometer and vibrating sample magnetometer.Under optimal experimental conditions,diethylstilbestrol（DES）,dienestrol（DE）and hexestrol（HEX）had a good linear relationship in the range of 1.0×10-7～1.0×10-5mol/L（R2greater than 0.9875）.The detection limits were 8.07×10-8mol/L,7.71×10-8mol/L and 8.11×10-8mol/L（S/N=3）,respectively.The standard recoveries ranged from 87.6%to 102.0%,RSDs of peak height and migration time were lower than 4.9%（n=5）.The method is fast,environmentally friendly,sensitive and selective.2.A magnetic solid phase extraction-column cyclodextrin to adsorption micellar microextraction dual-concentration capillary electrophoresis method was established.It is also used to detect three sulfonamides（SAs）in environmental water samples.Under optimal experimental conditions,the linear correlation coefficients of sulfadimethymidine（SM2）,sulfadiazine（SD）and sulfathiazole（STZ）were all greater than 0.9900.The detection limits were 6.47×10-9,8.39×10-9and 6.66×10-9mol/L（S/N=3）,respectively.The three SAs were separated at baseline within 8 min,and the enrichment ratio reached 155～167.The recoveries were in the range of 85.2%～102.0%.RSDs of peak height and migration time were less than 5.8%（n=5）.The proposed method is fast and sensitive,which provides an alternative scheme for the analysis of sulfonamides residues. |
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