Surface Molecularly Imprinted Materials For Bisphenol A:Preparations Performances And Applications

Bisphenol A (BPA) as a kind of endocrine disruption estrogens, has wide application in modern industry, such as being used in the production of polycarbonate, epoxy resin and important engineering plastics. However, the BPA can be migrated into the food once used as the material in food cans. What’s more, it may pollute the underground water and surface water through various means. So it may have potential health risks to the people. So it is very important to monitor bisphenol A of food and drinking water samples to guarantee human’s health. To develop a sorbent, which has a rapid, large amount of adsorption capacity, high repeatable utilization rate and good selectivity to separate and enrich in bisphenol A in complex samples, is a hot research topic in the field of analysis. In this paper, we synthesized two kinds of molecularly imprinted polymer of BPA, and used them as a new packing of solid phase extraction to the enrich and separate BPA of trace concentrations in complex samples. Finally, we established a molecularly imprinted-solid phase extraction-high performance liquid chromatography (MIP-SPE-HPLC) new method for determination of BPA in water and drinks. The main results as follows:The novel hollow porous dummy molecularly imprinted polymer (HPDMIP) was prepared adopting a sacrificial support approach, using tetrabromobisphenol A (TBBPA), whose structure was similar to that of BPA, as the dummy template and mesoporous MCM-48nanospheres as the support. Scanning electron microscopy, fourier infrared spectrum and transmission electron microscopy had been used to characterize the properties such as physical morphology of the result polymer nanospheres. It turned out to show that the structure of hollow porous dummy molecularly imprinted polymer had been formed, and also had good homogeneity and single dispersion.The performance of enrichment and separation of BPA and repeat utilization were evaluated. The maximum adsorption capacities (Qmax) of the dummy-imprinted and non-imprinted sorbents for BPA were as high as445and340μmol g-1, respectively, and the adsorption reached about73%of Qmax in10min. Meanwhile, a method was developed for the determination of BPA using HPDMIP as a solid-phase extraction enrichment sorbent coupled with HPLC. Under the optimum experimental conditions, HPDMIP exhibited satisfactory results in the enrichment and determination of BPA in tap water with a recovery rate of95～105%, and relative standard deviations of below6%, and it can achieve a limit of detection as low as3ng mL-1.The magnetic nanosphere was prepared by hydrothermal synthesis directly. And ethyl silicate as the crosslinking agent, bisphenol A was as imprinted template,3-ammonia propyl triethoxy silane as functional monomer, magnetic nanoparticles as nuclear to synthesis magnetic surface molecular imprinted polymer. Scanning electron microscopy, fourier infrared spectrum and transmission electron microscopy had been used to characterize the properties such as physical morphology of the result polymer nanospheres. The performances of enrichment and separation of BPA were evaluated. The results show that the magnetic surface molecular imprinted polymer had a larger adsorption capacity (280μmol g-1) and a fast adsorption rate. The preparated material s were firstly used in SPE for separation and enrichment of trace BPA in drinks and fruits combined with the technique of HPLC. The predominant factors, such as the eluent and breakthrough volume that may influence the adsorption recoveries of BPA were optimized in the experiments, finally the best conditions were selected. Studies have shown that maximum extraction volume is800mL. Under the condition of coexistence of BPA analogs, magnetic solid phase extraction to BPA high selective extraction effect; A MSPE-HPLC method for the determination of BPA in environmental water samples was established, the linear range of the method is5.7～2280ng mL-1, the correlation coefficient is greater than0.999, and the detection limit of3ng mL-1. Standard recovery rate of the method for determination of BPA in drinks are between93.5～110.3%, the results are satisfactory.