Study On The Adsorption And Detection Of Typical Endocrine Disrupting Chemicals By Magnetic Porous Organic Cages

Endocrine disrupting chemicals（EDCs）can destroy the endocrine system of human body and mainly in the form of trace amounts in human and environmental media..Parabens are mainly used as preservatives,antibacterial agents and food additives,widely existing in food and personal care products.Commonly used as plasticizers,bisphenol A can be detected in food packing and baby bottles.Bisphenol A is the most common bisphenol,with annual global production of 8 million tons.Diethylstilbestrol and ethinyl estradiol are two synthetic estrogens found in animal growth promoters and female oral contraceptives,respectively.In recent years,due to the widespread use of EDCs,EDCs can be found in drinking water,urine,animals and plants,air,soil,breast tissue,etc.Long-term exposure to EDCs will induce neurotoxicity,immunotoxicity,estrogen activity.Therefore,it is necessary to degrade EDCs in the environment.Adsorption method is a relatively simple and economical separation and enrichment method,while magnetic solid phase extraction（MSPE）is a pretreatment method that does not require centrifugation and has a high separation speed.At present,gas chromatography-tandem mass spectrometry（GC-MS）and high performance liquid chromatography-tandem mass spectrometry（HPLC-MS/MS）are mainly used to detect EDCs.GC-MS often requires derivatization,which requires many reagents and takes a long time,HPLC-MS/MS has high sensitivity and reproducibility,and can detect trace EDCs without derivatization.Therefore,there is a need to develop an efficient and simple pretreatment method,combined with adsorbent materials,for the detection of trace EDCs in the environment using HPLC-MS/MS.Based on this,three kinds of adsorption materials were prepared by hydrophobic-hydrophobic interaction,hydrogen bond and strongπ-πinteraction.Finally,magnetic porous organic cage was selected as the best adsorption material and combined with HPLC-MS/MS to detect EDCs in environmental water.The content is as follows:（1）According to previous reports,the porous organic cage CC3R-OH was prepared,the magnetic nanoparticles Fe₃O₄-COOH were prepared by solvothermal method,and the magnetic porous organic cage Fe₃O₄-COOH@CC3R-OH was prepared by modification.The structure of the porous organic cage CC3R-OH was determined by NMR and matrix-assisted laser resolution time-of-flight mass spectrometry,and then the three materials CC3R-OH,Fe₃O₄-COOH and Fe₃O₄-COOH@CC3R-OH were characterized by field emission scanning electron microscopy and transmission electron microscopy,and further characterization of the material by Fourier transform infrared spectroscopy,water contact angle,thermogravimetric analysis,nitrogen physisorption-desorption,X-ray powder diffraction and magnetic hysteresis loop,the results showed Fe₃O₄-COOH and Fe₃O₄-COOH@CC3R-OH was successfully prepared,and Fe₃O₄-COOH nanoparticles were attached to the porous organic cage CC3R-OH.（2）The adsorption effect of three materials,CC3R-OH,Fe₃O₄-COOH and Fe₃O₄-COOH@CC3R-OH,was explored and the adsorption conditions were optimized.The adsorption effects of three materials for methyl,ethyl,propyl and butyl parabens,bisphenol A,bisphenol B,diethylstilbestrol and ethinylestradiol were compared,and the results showed that Fe₃O₄-COOH@CC3R-OH performed the best,and then Fe₃O₄-COOH@CC3R-OH was used as the optimal adsorbent to optimize the adsorption conditions,and the optimal adsorption conditions were obtained as:The loading concentration was 1 ng/m L,the volume was 10 m L,the adsorption mass was 13 mg,the eluent was acetonitrile,the elution volume was 5 m L,the 100%pure water was used for washing,and the adsorption time was 8 min.After 6 cycles of regeneration,there is still a good recovery rate.Finally,the adsorption mechanism and adsorption behavior of Fe₃O₄-COOH@CC3R-OH were investigated by adsorption isotherms and adsorption kinetics under the optimal adsorption conditions.The maximum adsorption capacities of Butylparaben（Bu P）and Bisphenol B（BPB）were 16.15and 13.51 mg/g,respectively.The adsorption kinetics experiments of Bu P and BPB showed that the adsorption process was more in line with the pseudo-second-order kinetics,and the R²was 0.9983 and 0.9988,respectively.（3）Magnetic porous organic cage Fe₃O₄-COOH@CC3R-OH magnetic solid phase extraction with high performance liquid chromatography-tandem mass spectrometry detection of EDCs in environmental water samples.Under optimal conditions,Fe₃O₄-COOH@CC3R-OH was used to adsorb EDCs in environmental water samples.The established method produced all peaks within 8 min.The linear correlation coefficient was between 0.9987 and 0.9997,and the linear range was 0.01 to 100 ng/m L,the relative standard deviations were all less than 15%.No EDCs were detected in the actual water samples,and the recovery rate of standard addition was between 70.9%and 103.9%.In summary,the adsorption efficiency of magnetic porous organic cage Fe₃O₄-COOH@CC3R-OH for methylparaben,ethylparaben,propylparaben and butylparaben,bisphenol A,bisphenol B,diethylstilbestrol and ethinylestradiol was more than 70%.Based on this material,a MSPE-HPLC-MS/MS analysis method was developed,which provides new adsorption materials and analytical techniques for the enrichment and detection of EDCs in the environment.