| Pharmaceutical and personal care products (PPCPs) presented in the environment is attracting increasing attention from researchers, which will not only pollute the environment, but also pose a potential harm to h human health.As a no solvent consumption pre-treatment technology, solid-phase microextraction (SPME) technology combines sampling, extraction, concentration and injection into one step, and it is promoted to be a "green" sample preparation technique. Due to the disadvantages of the commercial availably SPME fibers, such as poor solvent resistance, short life and high price, et al, development of a new coating has been the focus of the technology.In this work, glass capillary was chosen as a "mold" and stainless steel wire as substrate, a poly(methacrylic acid-ethylene glycol dimethacrylate)(MAA-EGDMA) coated SPME fiber was prepared by in-situ polymerization. With modification, the selective extraction of the target has also been improved. A SPME-HPLC method was established on the several typical PPCPs (tetracycline, sulfonamides and beta-receptor blockers) in the environment.The main works and results of this thesis are as follows:(1) The adhesive mechanisms of polydopamine were applied for the modification of the stainless steel wire, which was used to be the substrate of the preparation of a poly (MAA-EGDMA) coated SPME fiber, with a "mold" of glass capillary. In combination with HPLC, the method for determination of sulfonamide (SAs) from milk sample was proposed. The average thickness of poly (MAA-EGDMA) coated SPME fiber was30μm, and the fiber-to-fiber reproducibility was satisfactory. Several extraction parameters influencing on extraction efficiency were investigated, which including the pH of the sample matrix, extraction temperature, extraction time, desorption solvent and desorption time. The optimum extraction conditions were as follows:the sample solution pH of5, extraction time of50min, extraction temperature of30℃, desorption solvent of acetonitrile/formic acid (0.1%,20/80), desorption time of12min. High sensitivity and a wide linear range were obtained. The detection limit was below10μg/L. The method was applied to determination of four SAs in milk samples, with recoveries ranged from68.2%to100.3%.(2) The sulfuric acid was used for the modification of the poly(glycidyl methacrylate-ethylene glycol dimethacrylate)(GMA-EGDMA) coated fiber. Coupled to HPLC with DAD detection, a simple method for the analysis of four PPCPs in water was established. The hydroxylated poly(GMA-EGDMA) coated fiber exhibited good extraction efficiency for the high polar PPCPs in water. The detection limits of the four PPCPs were in the range of0.5-5μg/L. The proposed methods was successfully applied to the determination of the four PPCPs in real water samples, with good recoveries of70.6%-105.5%.(3) A novel molecularly imprinted polymer (MIP) coated SPME fiber was prepared with oxytetracycline (OTC) as the template molecule. Electron microscope photographs proved that the MIP coating was homogeneous and porous. The extraction selection of the MIP-coated fibers was much better than the non-imprinted polymer (NIP) coated fibers for the TCs, but there is no significant difference for the other two SAs. The method for the determination of TCs by the MIP-coated SPME coupled with HPLC was developed, and the optimized extraction conditions were studied. The developed method was applied to the determination of three TCs in the spiked water and milk samples with the recoveries ranging from97.8%to109.0%. The result demonstrates that the MDP-coated fiber is suitable for the selective extraction of trace TCs in complicated samples. |
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