Preparation And Properties Of Dual-Templates Magnetic Molecularly Imprinted Materials For Adsorption Of Estradiol And Diethylstilbestrol

Estradiol(E2)is one of the representative substances of endocrine disruptors and belongs to a kind of natural estrogen,which is widely present in the natural environment.According to current research,lower concentrations of estradiol have an adverse effect on the ecological environment and human health.Diethylstilbestrol(DES)is the first active oral synthetic hormone that has been used as a growth promoter for livestock.It can seriously interfere with the metabolic process and reproductive development of organisms at trace levels.Therefore,in order to analyze and detect estradiol and diethylstilbestrol in complex environmental samples,it is necessary to establish a fast,convenient and simple pretreatment method,and cooperate with modern high-efficiency detection technology to analyze and detect estradiol and diethylstilbestrol in complex samples.In this study,estradiol and diethylstilbestrol were used as template molecules,and a novel double template molecularly imprinted magnetic polymer coated stir bar(MMIP)was prepared by molecular imprinting self-assembly technique using a magnetic stir bar as a carrier.Liquid chromatography(HPLC)analysis detected the template molecules estradiol and diethylstilbestrol.A dual template molecularly imprinted magnetic polymer coating stir bar-high performance liquid chromatography(HPLC)was developed for the determination of estradiol and diethylstilbestrol in complex environmental samples.The method was successfully applied to the analysis of actual water samples such as deionized water,tap water and reservoir water.The optimum dosage and ratio of each synthetic raw material were obtained through optimization experiments to determine the optimal reaction conditions.SEM and FTIR were used to analyze the apparent morphology and structure of the molecularly imprinted polymer.The Scatchard model was used to fit and analyze the molecularly imprinted polymer.Synthesis and adsorption principle.The adsorption and desorption conditions of the molecularly imprinted magnetic polymer coating stir bar for estradiol and diethylstilbestrol were optimized to determine the optimal conditions.The molecularly imprinted magnetic polymer coating stir bar was also used to adsorb estradiol and diethylstilbestrol.Dynamics and thermodynamic processes.The experimental results showed that the maximum adsorption capacities of MMIP for estradiol and diethylstilbestrol were 21.07 mg/g and 17.08 mg/g,respectively,and the adsorption equilibrium was basically reached after 90 min.The spiked recovery experiments were carried out in three kinds of actual water bodies.The recoveries were 80%~92% and 80%~91%,the relative standard deviation(RSD)was 4.5%~8.5% and 4.3%~8.4%.Selective adsorption of estradiol and diethylstilbestrol molecularly imprinted magnetic polymer coating stir bar was studied,and interfering substances such as estrone,estriol,bisphenol A,tetrabromobisphenol A,phenol and sulfamethoxazole were selected.The experimental results show that the interfering substances will reduce the saturated adsorption capacity of MMIP for estradiol and diethylstilbestrol,and will not affect the selective adsorption of MMIP.Therefore,MMIP has better selective adsorption for estradiol and diethylstilbestrol.