Preparation Of Cationic Porous Materials And Their Enrichment Application Of Endocrine Disruptors

Endocrine disrupting compounds?EDCs?are a class of exogenous compounds,which widely exist in the atmosphere,soil and water environment.They are also reported to be found in food and food packaging materials.EDCs are easily enriched in organisms and the environment.They also have obvious side effects on the human body at very low concentrations.They interfere with the physiological processes of endogenous hormones,such as production,release,transmission and metabolism,and cause diseases such as reproductive system abnormalities,diabetes,obesity and cancer.EDCs usually exist at very low concentrations.Efficient and sensitive analytical methods are the key to the detection and monitoring of EDCs.Solid phase extraction,combines sample extraction and concentration,is a common enrichment technology for the analysis of low concentration EDCs.In this work,porous carbon and porous silicon with stable properties,low price,simple synthesis steps and easy modification were selected as solid phase extraction adsorbents,and positive charge modification was carried out to improve the adsorption effect on phenolic EDCs.At the same time,in order to improve the detection of low concentration samples,a new fluorescent probe,benzimidazo[2,1-b]quinazoline-12?6H?-one-5-ethylimidazole ester?BQEIC?was designed and synthesized,which effectively improved the sensitivity of liquid chromatography analysis and ensured the analysis effect.In this study,dispersed solid phase microextraction based on cationic porous materials combined with high sensitive liquid chromatography was successfully applied to the analysis of the water samples and migration of food contact materials,and good results were obtained.The main works are as follow:Chapter One:EDCs were briefly introduced.Porous materials and their applications in solid phase extraction were briefly described.Finally,the recent developments of high performance liquid chromatography?HPLC?were introduced.Chapter Two:Dimethyloctadecyl[3-?trimethoxysilyl?propyl]ammoniumchloride?a quaternary ammonium salt with long hydrophobic chain?was synthesized to modify MCM-48porous silicon as a new adsorbent for dispersed solid phase extraction?DSPE?.A series of MCM-48 materials with different functionalities were synthesized and used as reference materials for the research mechanism,and their adsorption properties were evaluated.A new fluorescent probe,BQEIC,was synthesized and used to evaluate the analysis effect of DSPE.The results show that quaternary ammonium salt functionalized MCM-48 porous silica can be used as an ideal adsorbent for EDCs enrichment from water,and the recovery is higher than 95%.The method has been successfully applied to the enrichment and analysis of seven EDCs in environmental water samples.Chapter Three:A cationic gemini surfactant templated magnetic cubic porous silica Fe₃O₄@14-3-14-MCM-48 nanocomposite was synthesized as a adsorbent for magnetic dispersion solid phase extraction?MDSPE?enriched nine EDCs from migrants of food contact materials and analyzed in combination with high performance liquid chromatography and diode array detectors?HPLC-DAD?.The results showed that Fe₃O₄@14-3-14-MCM-48 could be used as an ideal adsorbent for enriching EDCs from migrants of food contact materials with good recovery of 92.6%.Chapter Four:A magnetic cationic resorcinol/formaldehyde resin?Fe₃O₄@CTAB-RF?was synthesized,and cationic surfactants were introduced into the magnetic resorcinol/formaldehyde resin to increase the electrostatic interaction between the resins and phenolic analyses.It was applied to the enrichment of EDCs from migrants of food contact materials in MDSPE and analyzed by high performance liquid chromatography?HPLC?.The results showed that Fe₃O₄@CTAB-RF could be used as an ideal adsorbent for enriching EDCs from migrants of food contact materials with a good recovery of 90.6%.