| Solid-Phase Microextraction(SPME), a novel solvent-free method, integrates extraction, concentration and sample introduction in one step; it's not only much quicker and simpler than conventional methods, but also sensitive, portable, and easily combined with other instruments, such as gas chromatography, high-performance liquid chromatography, capillary electrophoresis etc. Till now, this technique has mainly been developed in extraction modes, extraction theory, coupled equipment, coating material and coating technology. But there is still much more work needed to do. Since in real application, the material of SPME coating determines the detection sensitivity and selectivity. The development of material of Solid-Phase Microextraction coating is the important aspect in SPME. Therefore making more novel solid phase coatings can enable the SPME more adaptable in more fields.In most cases, commercial SPME fiber can successfully analyze the compounds with non-polarity or medium polarity, but for polar compounds, it can only deal with their derivative countparts. According to such a theorem "It's easier for analogical substances to dissolve each other", the key part consists in searching the steady and polar coating material. What's more, commercial SPME fiber is fragile, too expensive, and short-life. These shortcomings limit the range of SPME usage. Therefore, the aim of this paper is to exploit new SPME coating material with high selectivity, high sensitivity, thermal stability and long life. In this paper, we developed two kinds of coating material, and prepared three SPME fibers based on these materials.Nafion, a perfluorosulfonate ionomer, is widely applied in electrochemistry. Nafion solution is easy to form membrane by vaporizing, which mainly used as separating membrane in electrolytic cells, a solid polymer electrolyte in fuel cells and batteries, and electrode coating. Its resistance to chemical attack and thermal stability, in addition to its high mechanical strength, make it ideal for applications where SPME is required. We prepared Nafion fiber and Nafion/AC fiber. The coating methods are described in chapter 3 and chapter 4 in detail.Polypyrrole(Ppy) is one kind of conducting polymers. It has such good properties as high stability, strong adsorption, easy preparation, various derivatives, etc, which enable it a good candidate to be SPME coating material. Studies from foreign researchers show this material can extract not only volatile, less volatile compounds but also ions in extraction solution. The last chapter of this paper studied the methods for Ppy coating preparation under different electrochemical conditions. In the experiment, we polymerized pyrrole on carbon fiber to produce the new SPME fiber, i.e., a carbon fiber enwrapped in ploypyrrole. We also found this fiber has a porous structure film and good tenacity.The preparation conditions of these fibers and their properties were investigated respectively in each chapter, for example, extraction time, extraction temperature, desorption time, desorption temperature, extraction amounts, selectivity, detection limits, linear range andusing life. The extraction ability of Nafion and Nafion/AC fiber was compared with commercial fiber and the results show our fibers are better in specified aspects. The extraction and analysis of alcohols and esters are carried out respectively. The fibers were also used to determine methanol in wine, ethyl acetate in lake water, ethanol in pickles extraction solution. The results show that these fibers are suitable for the efficient extraction of these polar compounds.
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