Study On Molecular Imprinted Technology Coupled With CE For Determining Of BPA In Different Complex Samples

Bisphenol A (BPA), a well known environmental estrogen, has biotoxic and endocrine-disrupting effects, wildly exits in environmental, biological and food samples at a trace amount. So it is necessary to develop a fast, sensitive, high selective and cheap method for determination BPA in complex sample matrices.Molecular imprinted technology is based on the molecular recognition theory,and its main procedure is to synthesize molecular imprinted polymers(MIPs). Because MIPs have chemical stability and selective combination with the target analyte, they have been widely used in environmental, biological and clinical samples. Capillary electrophoresis (CE) is a noble analytical technique in analytical chemistry which has some advantages, such as highly efficient and rapid analysis.In this thesis, a new high selective, fast and effective sample pretreatment technique-molecular imprinted solid-phase extraction (MISPE) was achieved by combination of molecular imprinted technology and solid-phase extraction (SPE). It was the first time to determine BPA in complex sample matrices by MISPE coupled with CE. The main contents in this thesis are described as follows:1. In this paper, the molecular imprinted technology was systematically summed up. Synthetic methods of molecularly imprinted polymers and application of the molecular imprinted technology in analytical chemistry were particularly outlined.2. Bisphenol A imprinted polymers were synthesized by precipitation polymerization, and effects of the preparing condition, such as the ratio and volume of the porogenic solvent, the sorts of the functional monomers and the amount of template on the maximum absorption capacity and imprinted effect of the polymers were investigated. At last, 4-VP and 60ml acetonitrile were used as functional monomer and porogenic solvent, respectively, the amount of the bisphenol A was 6mmol. Under this optimal condition, regulary microspheres were obtained, the values of imprinted factor and Bmax were 6.53 and 1.37×10^-5mol/g, respectively.3. The optimal separation condition of CE were pH=11.5, voltage=18kv. Under the optimal condition, BPA and its analogues were separated in 15 min. The washing and eluting protocols of MISPE were optimized, then the recoveries and the relative standard deviations (RSD) were investigated. It was showed the recoveries were basically same when samples of different volumes were loaded, RSD<5.8, and the recoveries changed from 71.20% to 86.23% for different sample matrices. Compared with C18 SPE, the MISPE has higher selectivity and recovery for BPA. At last, BPA was determined in tap water, chemical plant waste water, Yangtse River water, Yangtse River soil, shrimp and human urine samples by MISPE coupled with CE, and good recovery and limit of detection (LOD) were obtained, spiked recoveries was from 93.69% to 105.4%, LOD in aqueous sample, solid sample and human urine sample were 3.0⁶.9μg/l,1.8².1μg/g and 84μg/l, respectively.